IOUtils.java
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.commons.io;
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.ByteArrayInputStream;
import java.io.CharArrayWriter;
import java.io.Closeable;
import java.io.EOFException;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.io.PipedInputStream;
import java.io.PipedOutputStream;
import java.io.Reader;
import java.io.UncheckedIOException;
import java.io.Writer;
import java.net.HttpURLConnection;
import java.net.ServerSocket;
import java.net.Socket;
import java.net.URI;
import java.net.URL;
import java.net.URLConnection;
import java.nio.ByteBuffer;
import java.nio.CharBuffer;
import java.nio.channels.Channels;
import java.nio.channels.ReadableByteChannel;
import java.nio.channels.Selector;
import java.nio.charset.Charset;
import java.nio.charset.StandardCharsets;
import java.nio.file.Files;
import java.util.Arrays;
import java.util.Collection;
import java.util.Iterator;
import java.util.List;
import java.util.Objects;
import java.util.function.Consumer;
import java.util.function.Supplier;
import java.util.stream.Collectors;
import java.util.stream.Stream;
import java.util.zip.InflaterInputStream;
import org.apache.commons.io.function.IOConsumer;
import org.apache.commons.io.function.IOSupplier;
import org.apache.commons.io.function.IOTriFunction;
import org.apache.commons.io.input.CharSequenceReader;
import org.apache.commons.io.input.QueueInputStream;
import org.apache.commons.io.output.AppendableWriter;
import org.apache.commons.io.output.ByteArrayOutputStream;
import org.apache.commons.io.output.NullOutputStream;
import org.apache.commons.io.output.NullWriter;
import org.apache.commons.io.output.StringBuilderWriter;
import org.apache.commons.io.output.ThresholdingOutputStream;
import org.apache.commons.io.output.UnsynchronizedByteArrayOutputStream;
/**
* General IO stream manipulation utilities.
* <p>
* This class provides static utility methods for input/output operations.
* </p>
* <ul>
* <li>closeQuietly - these methods close a stream ignoring nulls and exceptions
* <li>toXxx/read - these methods read data from a stream
* <li>write - these methods write data to a stream
* <li>copy - these methods copy all the data from one stream to another
* <li>contentEquals - these methods compare the content of two streams
* </ul>
* <p>
* The byte-to-char methods and char-to-byte methods involve a conversion step.
* Two methods are provided in each case, one that uses the platform default
* encoding and the other which allows you to specify an encoding. You are
* encouraged to always specify an encoding because relying on the platform
* default can lead to unexpected results, for example when moving from
* development to production.
* </p>
* <p>
* All the methods in this class that read a stream are buffered internally.
* This means that there is no cause to use a {@link BufferedInputStream}
* or {@link BufferedReader}. The default buffer size of 4K has been shown
* to be efficient in tests.
* </p>
* <p>
* The various copy methods all delegate the actual copying to one of the following methods:
* </p>
* <ul>
* <li>{@link #copyLarge(InputStream, OutputStream, byte[])}</li>
* <li>{@link #copyLarge(InputStream, OutputStream, long, long, byte[])}</li>
* <li>{@link #copyLarge(Reader, Writer, char[])}</li>
* <li>{@link #copyLarge(Reader, Writer, long, long, char[])}</li>
* </ul>
* For example, {@link #copy(InputStream, OutputStream)} calls {@link #copyLarge(InputStream, OutputStream)}
* which calls {@link #copy(InputStream, OutputStream, int)} which creates the buffer and calls
* {@link #copyLarge(InputStream, OutputStream, byte[])}.
* <p>
* Applications can re-use buffers by using the underlying methods directly.
* This may improve performance for applications that need to do a lot of copying.
* </p>
* <p>
* Wherever possible, the methods in this class do <em>not</em> flush or close
* the stream. This is to avoid making non-portable assumptions about the
* streams' origin and further use. Thus the caller is still responsible for
* closing streams after use.
* </p>
* <p>
* Provenance: Excalibur.
* </p>
*/
public class IOUtils {
// NOTE: This class is focused on InputStream, OutputStream, Reader and
// Writer. Each method should take at least one of these as a parameter,
// or return one of them.
/**
* CR char '{@value}'.
*
* @since 2.9.0
*/
public static final int CR = '\r';
/**
* The default buffer size ({@value}) to use in copy methods.
*/
public static final int DEFAULT_BUFFER_SIZE = 8192;
/**
* The system directory separator character.
*/
public static final char DIR_SEPARATOR = File.separatorChar;
/**
* The UNIX directory separator character '{@value}'.
*/
public static final char DIR_SEPARATOR_UNIX = '/';
/**
* The Windows directory separator character '{@value}'.
*/
public static final char DIR_SEPARATOR_WINDOWS = '\\';
/**
* A singleton empty byte array.
*
* @since 2.9.0
*/
public static final byte[] EMPTY_BYTE_ARRAY = {};
/**
* Represents the end-of-file (or stream) value {@value}.
* @since 2.5 (made public)
*/
public static final int EOF = -1;
/**
* LF char '{@value}'.
*
* @since 2.9.0
*/
public static final int LF = '\n';
/**
* The system line separator string.
*
* @deprecated Use {@link System#lineSeparator()}.
*/
@Deprecated
public static final String LINE_SEPARATOR = System.lineSeparator();
/**
* The UNIX line separator string.
*
* @see StandardLineSeparator#LF
*/
public static final String LINE_SEPARATOR_UNIX = StandardLineSeparator.LF.getString();
/**
* The Windows line separator string.
*
* @see StandardLineSeparator#CRLF
*/
public static final String LINE_SEPARATOR_WINDOWS = StandardLineSeparator.CRLF.getString();
/**
* Internal byte array buffer, intended for both reading and writing.
*/
private static final ThreadLocal<byte[]> SCRATCH_BYTE_BUFFER_RW = ThreadLocal.withInitial(IOUtils::byteArray);
/**
* Internal byte array buffer, intended for write only operations.
*/
private static final byte[] SCRATCH_BYTE_BUFFER_WO = byteArray();
/**
* Internal char array buffer, intended for both reading and writing.
*/
private static final ThreadLocal<char[]> SCRATCH_CHAR_BUFFER_RW = ThreadLocal.withInitial(IOUtils::charArray);
/**
* Internal char array buffer, intended for write only operations.
*/
private static final char[] SCRATCH_CHAR_BUFFER_WO = charArray();
/**
* Returns the given InputStream if it is already a {@link BufferedInputStream}, otherwise creates a
* BufferedInputStream from the given InputStream.
*
* @param inputStream the InputStream to wrap or return (not null)
* @return the given InputStream or a new {@link BufferedInputStream} for the given InputStream
* @throws NullPointerException if the input parameter is null
* @since 2.5
*/
@SuppressWarnings("resource") // parameter null check
public static BufferedInputStream buffer(final InputStream inputStream) {
// reject null early on rather than waiting for IO operation to fail
// not checked by BufferedInputStream
Objects.requireNonNull(inputStream, "inputStream");
return inputStream instanceof BufferedInputStream ?
(BufferedInputStream) inputStream : new BufferedInputStream(inputStream);
}
/**
* Returns the given InputStream if it is already a {@link BufferedInputStream}, otherwise creates a
* BufferedInputStream from the given InputStream.
*
* @param inputStream the InputStream to wrap or return (not null)
* @param size the buffer size, if a new BufferedInputStream is created.
* @return the given InputStream or a new {@link BufferedInputStream} for the given InputStream
* @throws NullPointerException if the input parameter is null
* @since 2.5
*/
@SuppressWarnings("resource") // parameter null check
public static BufferedInputStream buffer(final InputStream inputStream, final int size) {
// reject null early on rather than waiting for IO operation to fail
// not checked by BufferedInputStream
Objects.requireNonNull(inputStream, "inputStream");
return inputStream instanceof BufferedInputStream ?
(BufferedInputStream) inputStream : new BufferedInputStream(inputStream, size);
}
/**
* Returns the given OutputStream if it is already a {@link BufferedOutputStream}, otherwise creates a
* BufferedOutputStream from the given OutputStream.
*
* @param outputStream the OutputStream to wrap or return (not null)
* @return the given OutputStream or a new {@link BufferedOutputStream} for the given OutputStream
* @throws NullPointerException if the input parameter is null
* @since 2.5
*/
@SuppressWarnings("resource") // parameter null check
public static BufferedOutputStream buffer(final OutputStream outputStream) {
// reject null early on rather than waiting for IO operation to fail
// not checked by BufferedInputStream
Objects.requireNonNull(outputStream, "outputStream");
return outputStream instanceof BufferedOutputStream ?
(BufferedOutputStream) outputStream : new BufferedOutputStream(outputStream);
}
/**
* Returns the given OutputStream if it is already a {@link BufferedOutputStream}, otherwise creates a
* BufferedOutputStream from the given OutputStream.
*
* @param outputStream the OutputStream to wrap or return (not null)
* @param size the buffer size, if a new BufferedOutputStream is created.
* @return the given OutputStream or a new {@link BufferedOutputStream} for the given OutputStream
* @throws NullPointerException if the input parameter is null
* @since 2.5
*/
@SuppressWarnings("resource") // parameter null check
public static BufferedOutputStream buffer(final OutputStream outputStream, final int size) {
// reject null early on rather than waiting for IO operation to fail
// not checked by BufferedInputStream
Objects.requireNonNull(outputStream, "outputStream");
return outputStream instanceof BufferedOutputStream ?
(BufferedOutputStream) outputStream : new BufferedOutputStream(outputStream, size);
}
/**
* Returns the given reader if it is already a {@link BufferedReader}, otherwise creates a BufferedReader from
* the given reader.
*
* @param reader the reader to wrap or return (not null)
* @return the given reader or a new {@link BufferedReader} for the given reader
* @throws NullPointerException if the input parameter is null
* @since 2.5
*/
public static BufferedReader buffer(final Reader reader) {
return reader instanceof BufferedReader ? (BufferedReader) reader : new BufferedReader(reader);
}
/**
* Returns the given reader if it is already a {@link BufferedReader}, otherwise creates a BufferedReader from the
* given reader.
*
* @param reader the reader to wrap or return (not null)
* @param size the buffer size, if a new BufferedReader is created.
* @return the given reader or a new {@link BufferedReader} for the given reader
* @throws NullPointerException if the input parameter is null
* @since 2.5
*/
public static BufferedReader buffer(final Reader reader, final int size) {
return reader instanceof BufferedReader ? (BufferedReader) reader : new BufferedReader(reader, size);
}
/**
* Returns the given Writer if it is already a {@link BufferedWriter}, otherwise creates a BufferedWriter from the
* given Writer.
*
* @param writer the Writer to wrap or return (not null)
* @return the given Writer or a new {@link BufferedWriter} for the given Writer
* @throws NullPointerException if the input parameter is null
* @since 2.5
*/
public static BufferedWriter buffer(final Writer writer) {
return writer instanceof BufferedWriter ? (BufferedWriter) writer : new BufferedWriter(writer);
}
/**
* Returns the given Writer if it is already a {@link BufferedWriter}, otherwise creates a BufferedWriter from the
* given Writer.
*
* @param writer the Writer to wrap or return (not null)
* @param size the buffer size, if a new BufferedWriter is created.
* @return the given Writer or a new {@link BufferedWriter} for the given Writer
* @throws NullPointerException if the input parameter is null
* @since 2.5
*/
public static BufferedWriter buffer(final Writer writer, final int size) {
return writer instanceof BufferedWriter ? (BufferedWriter) writer : new BufferedWriter(writer, size);
}
/**
* Returns a new byte array of size {@link #DEFAULT_BUFFER_SIZE}.
*
* @return a new byte array of size {@link #DEFAULT_BUFFER_SIZE}.
* @since 2.9.0
*/
public static byte[] byteArray() {
return byteArray(DEFAULT_BUFFER_SIZE);
}
/**
* Returns a new byte array of the given size.
*
* TODO Consider guarding or warning against large allocations...
*
* @param size array size.
* @return a new byte array of the given size.
* @throws NegativeArraySizeException if the size is negative.
* @since 2.9.0
*/
public static byte[] byteArray(final int size) {
return new byte[size];
}
/**
* Returns a new char array of size {@link #DEFAULT_BUFFER_SIZE}.
*
* @return a new char array of size {@link #DEFAULT_BUFFER_SIZE}.
* @since 2.9.0
*/
private static char[] charArray() {
return charArray(DEFAULT_BUFFER_SIZE);
}
/**
* Returns a new char array of the given size.
*
* TODO Consider guarding or warning against large allocations...
*
* @param size array size.
* @return a new char array of the given size.
* @since 2.9.0
*/
private static char[] charArray(final int size) {
return new char[size];
}
/**
* Clears any state.
* <ul>
* <li>Removes the current thread's value for thread-local variables.</li>
* <li>Sets static scratch arrays to 0s.</li>
* </ul>
* @see IO#clear()
*/
static void clear() {
SCRATCH_BYTE_BUFFER_RW.remove();
SCRATCH_CHAR_BUFFER_RW.remove();
Arrays.fill(SCRATCH_BYTE_BUFFER_WO, (byte) 0);
Arrays.fill(SCRATCH_CHAR_BUFFER_WO, (char) 0);
}
/**
* Closes the given {@link Closeable} as a null-safe operation.
*
* @param closeable The resource to close, may be null.
* @throws IOException if an I/O error occurs.
* @since 2.7
*/
public static void close(final Closeable closeable) throws IOException {
if (closeable != null) {
closeable.close();
}
}
/**
* Closes the given {@link Closeable}s as null-safe operations.
*
* @param closeables The resource(s) to close, may be null.
* @throws IOExceptionList if an I/O error occurs.
* @since 2.8.0
*/
public static void close(final Closeable... closeables) throws IOExceptionList {
IOConsumer.forAll(IOUtils::close, closeables);
}
/**
* Closes the given {@link Closeable} as a null-safe operation.
*
* @param closeable The resource to close, may be null.
* @param consumer Consume the IOException thrown by {@link Closeable#close()}.
* @throws IOException if an I/O error occurs.
* @since 2.7
*/
public static void close(final Closeable closeable, final IOConsumer<IOException> consumer) throws IOException {
if (closeable != null) {
try {
closeable.close();
} catch (final IOException e) {
if (consumer != null) {
consumer.accept(e);
}
}
}
}
/**
* Closes a URLConnection.
*
* @param conn the connection to close.
* @since 2.4
*/
public static void close(final URLConnection conn) {
if (conn instanceof HttpURLConnection) {
((HttpURLConnection) conn).disconnect();
}
}
/**
* Avoids the need to type cast.
*
* @param closeable the object to close, may be null
*/
private static void closeQ(final Closeable closeable) {
closeQuietly(closeable, null);
}
/**
* Closes a {@link Closeable} unconditionally.
*
* <p>
* Equivalent to {@link Closeable#close()}, except any exceptions will be ignored. This is typically used in
* finally blocks.
* <p>
* Example code:
* </p>
* <pre>
* Closeable closeable = null;
* try {
* closeable = new FileReader("foo.txt");
* // process closeable
* closeable.close();
* } catch (Exception e) {
* // error handling
* } finally {
* IOUtils.closeQuietly(closeable);
* }
* </pre>
* <p>
* Closing all streams:
* </p>
* <pre>
* try {
* return IOUtils.copy(inputStream, outputStream);
* } finally {
* IOUtils.closeQuietly(inputStream);
* IOUtils.closeQuietly(outputStream);
* }
* </pre>
* <p>
* Also consider using a try-with-resources statement where appropriate.
* </p>
*
* @param closeable the objects to close, may be null or already closed
* @since 2.0
*
* @see Throwable#addSuppressed(Throwable)
*/
public static void closeQuietly(final Closeable closeable) {
closeQuietly(closeable, null);
}
/**
* Closes a {@link Closeable} unconditionally.
* <p>
* Equivalent to {@link Closeable#close()}, except any exceptions will be ignored.
* <p>
* This is typically used in finally blocks to ensure that the closeable is closed
* even if an Exception was thrown before the normal close statement was reached.
* <br>
* <b>It should not be used to replace the close statement(s)
* which should be present for the non-exceptional case.</b>
* <br>
* It is only intended to simplify tidying up where normal processing has already failed
* and reporting close failure as well is not necessary or useful.
* <p>
* Example code:
* </p>
* <pre>
* Closeable closeable = null;
* try {
* closeable = new FileReader("foo.txt");
* // processing using the closeable; may throw an Exception
* closeable.close(); // Normal close - exceptions not ignored
* } catch (Exception e) {
* // error handling
* } finally {
* <strong>IOUtils.closeQuietly(closeable); // In case normal close was skipped due to Exception</strong>
* }
* </pre>
* <p>
* Closing all streams:
* <br>
* <pre>
* try {
* return IOUtils.copy(inputStream, outputStream);
* } finally {
* IOUtils.closeQuietly(inputStream, outputStream);
* }
* </pre>
* <p>
* Also consider using a try-with-resources statement where appropriate.
* </p>
* @param closeables the objects to close, may be null or already closed
* @see #closeQuietly(Closeable)
* @since 2.5
* @see Throwable#addSuppressed(Throwable)
*/
public static void closeQuietly(final Closeable... closeables) {
if (closeables != null) {
closeQuietly(Arrays.stream(closeables));
}
}
/**
* Closes the given {@link Closeable} as a null-safe operation while consuming IOException by the given {@code consumer}.
*
* @param closeable The resource to close, may be null.
* @param consumer Consumes the IOException thrown by {@link Closeable#close()}.
* @since 2.7
*/
public static void closeQuietly(final Closeable closeable, final Consumer<IOException> consumer) {
if (closeable != null) {
try {
closeable.close();
} catch (final IOException e) {
if (consumer != null) {
consumer.accept(e);
}
}
}
}
/**
* Closes an {@link InputStream} unconditionally.
* <p>
* Equivalent to {@link InputStream#close()}, except any exceptions will be ignored.
* This is typically used in finally blocks.
* </p>
* <p>
* Example code:
* </p>
* <pre>
* byte[] data = new byte[1024];
* InputStream in = null;
* try {
* in = new FileInputStream("foo.txt");
* in.read(data);
* in.close(); //close errors are handled
* } catch (Exception e) {
* // error handling
* } finally {
* IOUtils.closeQuietly(in);
* }
* </pre>
* <p>
* Also consider using a try-with-resources statement where appropriate.
* </p>
*
* @param input the InputStream to close, may be null or already closed
* @see Throwable#addSuppressed(Throwable)
*/
public static void closeQuietly(final InputStream input) {
closeQ(input);
}
/**
* Closes an iterable of {@link Closeable} unconditionally.
* <p>
* Equivalent calling {@link Closeable#close()} on each element, except any exceptions will be ignored.
* </p>
*
* @param closeables the objects to close, may be null or already closed
* @see #closeQuietly(Closeable)
* @since 2.12.0
*/
public static void closeQuietly(final Iterable<Closeable> closeables) {
if (closeables != null) {
closeables.forEach(IOUtils::closeQuietly);
}
}
/**
* Closes an {@link OutputStream} unconditionally.
* <p>
* Equivalent to {@link OutputStream#close()}, except any exceptions will be ignored.
* This is typically used in finally blocks.
* </p>
* <p>
* Example code:
* </p>
* <pre>
* byte[] data = "Hello, World".getBytes();
*
* OutputStream out = null;
* try {
* out = new FileOutputStream("foo.txt");
* out.write(data);
* out.close(); //close errors are handled
* } catch (IOException e) {
* // error handling
* } finally {
* IOUtils.closeQuietly(out);
* }
* </pre>
* <p>
* Also consider using a try-with-resources statement where appropriate.
* </p>
*
* @param output the OutputStream to close, may be null or already closed
* @see Throwable#addSuppressed(Throwable)
*/
public static void closeQuietly(final OutputStream output) {
closeQ(output);
}
/**
* Closes an {@link Reader} unconditionally.
* <p>
* Equivalent to {@link Reader#close()}, except any exceptions will be ignored.
* This is typically used in finally blocks.
* </p>
* <p>
* Example code:
* </p>
* <pre>
* char[] data = new char[1024];
* Reader in = null;
* try {
* in = new FileReader("foo.txt");
* in.read(data);
* in.close(); //close errors are handled
* } catch (Exception e) {
* // error handling
* } finally {
* IOUtils.closeQuietly(in);
* }
* </pre>
* <p>
* Also consider using a try-with-resources statement where appropriate.
* </p>
*
* @param reader the Reader to close, may be null or already closed
* @see Throwable#addSuppressed(Throwable)
*/
public static void closeQuietly(final Reader reader) {
closeQ(reader);
}
/**
* Closes a {@link Selector} unconditionally.
* <p>
* Equivalent to {@link Selector#close()}, except any exceptions will be ignored.
* This is typically used in finally blocks.
* </p>
* <p>
* Example code:
* </p>
* <pre>
* Selector selector = null;
* try {
* selector = Selector.open();
* // process socket
*
* } catch (Exception e) {
* // error handling
* } finally {
* IOUtils.closeQuietly(selector);
* }
* </pre>
* <p>
* Also consider using a try-with-resources statement where appropriate.
* </p>
*
* @param selector the Selector to close, may be null or already closed
* @since 2.2
* @see Throwable#addSuppressed(Throwable)
*/
public static void closeQuietly(final Selector selector) {
closeQ(selector);
}
/**
* Closes a {@link ServerSocket} unconditionally.
* <p>
* Equivalent to {@link ServerSocket#close()}, except any exceptions will be ignored.
* This is typically used in finally blocks.
* </p>
* <p>
* Example code:
* </p>
* <pre>
* ServerSocket socket = null;
* try {
* socket = new ServerSocket();
* // process socket
* socket.close();
* } catch (Exception e) {
* // error handling
* } finally {
* IOUtils.closeQuietly(socket);
* }
* </pre>
* <p>
* Also consider using a try-with-resources statement where appropriate.
* </p>
*
* @param serverSocket the ServerSocket to close, may be null or already closed
* @since 2.2
* @see Throwable#addSuppressed(Throwable)
*/
public static void closeQuietly(final ServerSocket serverSocket) {
closeQ(serverSocket);
}
/**
* Closes a {@link Socket} unconditionally.
* <p>
* Equivalent to {@link Socket#close()}, except any exceptions will be ignored.
* This is typically used in finally blocks.
* </p>
* <p>
* Example code:
* </p>
* <pre>
* Socket socket = null;
* try {
* socket = new Socket("http://www.foo.com/", 80);
* // process socket
* socket.close();
* } catch (Exception e) {
* // error handling
* } finally {
* IOUtils.closeQuietly(socket);
* }
* </pre>
* <p>
* Also consider using a try-with-resources statement where appropriate.
* </p>
*
* @param socket the Socket to close, may be null or already closed
* @since 2.0
* @see Throwable#addSuppressed(Throwable)
*/
public static void closeQuietly(final Socket socket) {
closeQ(socket);
}
/**
* Closes a stream of {@link Closeable} unconditionally.
* <p>
* Equivalent calling {@link Closeable#close()} on each element, except any exceptions will be ignored.
* </p>
*
* @param closeables the objects to close, may be null or already closed
* @see #closeQuietly(Closeable)
* @since 2.12.0
*/
public static void closeQuietly(final Stream<Closeable> closeables) {
if (closeables != null) {
closeables.forEach(IOUtils::closeQuietly);
}
}
/**
* Closes an {@link Writer} unconditionally.
* <p>
* Equivalent to {@link Writer#close()}, except any exceptions will be ignored.
* This is typically used in finally blocks.
* </p>
* <p>
* Example code:
* </p>
* <pre>
* Writer out = null;
* try {
* out = new StringWriter();
* out.write("Hello World");
* out.close(); //close errors are handled
* } catch (Exception e) {
* // error handling
* } finally {
* IOUtils.closeQuietly(out);
* }
* </pre>
* <p>
* Also consider using a try-with-resources statement where appropriate.
* </p>
*
* @param writer the Writer to close, may be null or already closed
* @see Throwable#addSuppressed(Throwable)
*/
public static void closeQuietly(final Writer writer) {
closeQ(writer);
}
/**
* Consumes bytes from a {@link InputStream} and ignores them.
* <p>
* The buffer size is given by {@link #DEFAULT_BUFFER_SIZE}.
* </p>
*
* @param input the {@link InputStream} to read.
* @return the number of bytes copied. or {@code 0} if {@code input is null}.
* @throws NullPointerException if the InputStream is {@code null}.
* @throws IOException if an I/O error occurs.
* @since 2.8.0
*/
public static long consume(final InputStream input) throws IOException {
return copyLarge(input, NullOutputStream.INSTANCE);
}
/**
* Consumes characters from a {@link Reader} and ignores them.
* <p>
* The buffer size is given by {@link #DEFAULT_BUFFER_SIZE}.
* </p>
*
* @param input the {@link Reader} to read.
* @return the number of bytes copied. or {@code 0} if {@code input is null}.
* @throws NullPointerException if the Reader is {@code null}.
* @throws IOException if an I/O error occurs.
* @since 2.12.0
*/
public static long consume(final Reader input) throws IOException {
return copyLarge(input, NullWriter.INSTANCE);
}
/**
* Compares the contents of two Streams to determine if they are equal or
* not.
* <p>
* This method buffers the input internally using
* {@link BufferedInputStream} if they are not already buffered.
* </p>
*
* @param input1 the first stream
* @param input2 the second stream
* @return true if the content of the streams are equal or they both don't
* exist, false otherwise
* @throws IOException if an I/O error occurs
*/
public static boolean contentEquals(final InputStream input1, final InputStream input2) throws IOException {
// Before making any changes, please test with
// org.apache.commons.io.jmh.IOUtilsContentEqualsInputStreamsBenchmark
if (input1 == input2) {
return true;
}
if (input1 == null || input2 == null) {
return false;
}
// reuse one
final byte[] array1 = getScratchByteArray();
// allocate another
final byte[] array2 = byteArray();
int pos1;
int pos2;
int count1;
int count2;
while (true) {
pos1 = 0;
pos2 = 0;
for (int index = 0; index < DEFAULT_BUFFER_SIZE; index++) {
if (pos1 == index) {
do {
count1 = input1.read(array1, pos1, DEFAULT_BUFFER_SIZE - pos1);
} while (count1 == 0);
if (count1 == EOF) {
return pos2 == index && input2.read() == EOF;
}
pos1 += count1;
}
if (pos2 == index) {
do {
count2 = input2.read(array2, pos2, DEFAULT_BUFFER_SIZE - pos2);
} while (count2 == 0);
if (count2 == EOF) {
return pos1 == index && input1.read() == EOF;
}
pos2 += count2;
}
if (array1[index] != array2[index]) {
return false;
}
}
}
}
// TODO Consider making public
private static boolean contentEquals(final Iterator<?> iterator1, final Iterator<?> iterator2) {
while (iterator1.hasNext()) {
if (!iterator2.hasNext()) {
return false;
}
if (!Objects.equals(iterator1.next(), iterator2.next())) {
return false;
}
}
return !iterator2.hasNext();
}
/**
* Compares the contents of two Readers to determine if they are equal or not.
* <p>
* This method buffers the input internally using {@link BufferedReader} if they are not already buffered.
* </p>
*
* @param input1 the first reader
* @param input2 the second reader
* @return true if the content of the readers are equal or they both don't exist, false otherwise
* @throws NullPointerException if either input is null
* @throws IOException if an I/O error occurs
* @since 1.1
*/
public static boolean contentEquals(final Reader input1, final Reader input2) throws IOException {
if (input1 == input2) {
return true;
}
if (input1 == null || input2 == null) {
return false;
}
// reuse one
final char[] array1 = getScratchCharArray();
// but allocate another
final char[] array2 = charArray();
int pos1;
int pos2;
int count1;
int count2;
while (true) {
pos1 = 0;
pos2 = 0;
for (int index = 0; index < DEFAULT_BUFFER_SIZE; index++) {
if (pos1 == index) {
do {
count1 = input1.read(array1, pos1, DEFAULT_BUFFER_SIZE - pos1);
} while (count1 == 0);
if (count1 == EOF) {
return pos2 == index && input2.read() == EOF;
}
pos1 += count1;
}
if (pos2 == index) {
do {
count2 = input2.read(array2, pos2, DEFAULT_BUFFER_SIZE - pos2);
} while (count2 == 0);
if (count2 == EOF) {
return pos1 == index && input1.read() == EOF;
}
pos2 += count2;
}
if (array1[index] != array2[index]) {
return false;
}
}
}
}
// TODO Consider making public
private static boolean contentEquals(final Stream<?> stream1, final Stream<?> stream2) {
if (stream1 == stream2) {
return true;
}
if (stream1 == null || stream2 == null) {
return false;
}
return contentEquals(stream1.iterator(), stream2.iterator());
}
// TODO Consider making public
private static boolean contentEqualsIgnoreEOL(final BufferedReader reader1, final BufferedReader reader2) {
if (reader1 == reader2) {
return true;
}
if (reader1 == null || reader2 == null) {
return false;
}
return contentEquals(reader1.lines(), reader2.lines());
}
/**
* Compares the contents of two Readers to determine if they are equal or
* not, ignoring EOL characters.
* <p>
* This method buffers the input internally using
* {@link BufferedReader} if they are not already buffered.
* </p>
*
* @param reader1 the first reader
* @param reader2 the second reader
* @return true if the content of the readers are equal (ignoring EOL differences), false otherwise
* @throws NullPointerException if either input is null
* @throws UncheckedIOException if an I/O error occurs
* @since 2.2
*/
@SuppressWarnings("resource")
public static boolean contentEqualsIgnoreEOL(final Reader reader1, final Reader reader2) throws UncheckedIOException {
if (reader1 == reader2) {
return true;
}
if (reader1 == null || reader2 == null) {
return false;
}
return contentEqualsIgnoreEOL(toBufferedReader(reader1), toBufferedReader(reader2));
}
/**
* Copies bytes from an {@link InputStream} to an {@link OutputStream}.
* <p>
* This method buffers the input internally, so there is no need to use a {@link BufferedInputStream}.
* </p>
* <p>
* Large streams (over 2GB) will return a bytes copied value of {@code -1} after the copy has completed since
* the correct number of bytes cannot be returned as an int. For large streams use the
* {@link #copyLarge(InputStream, OutputStream)} method.
* </p>
*
* @param inputStream the {@link InputStream} to read.
* @param outputStream the {@link OutputStream} to write.
* @return the number of bytes copied, or -1 if greater than {@link Integer#MAX_VALUE}.
* @throws NullPointerException if the InputStream is {@code null}.
* @throws NullPointerException if the OutputStream is {@code null}.
* @throws IOException if an I/O error occurs.
* @since 1.1
*/
public static int copy(final InputStream inputStream, final OutputStream outputStream) throws IOException {
final long count = copyLarge(inputStream, outputStream);
return count > Integer.MAX_VALUE ? EOF : (int) count;
}
/**
* Copies bytes from an {@link InputStream} to an {@link OutputStream} using an internal buffer of the
* given size.
* <p>
* This method buffers the input internally, so there is no need to use a {@link BufferedInputStream}.
* </p>
*
* @param inputStream the {@link InputStream} to read.
* @param outputStream the {@link OutputStream} to write to
* @param bufferSize the bufferSize used to copy from the input to the output
* @return the number of bytes copied.
* @throws NullPointerException if the InputStream is {@code null}.
* @throws NullPointerException if the OutputStream is {@code null}.
* @throws IOException if an I/O error occurs.
* @since 2.5
*/
public static long copy(final InputStream inputStream, final OutputStream outputStream, final int bufferSize)
throws IOException {
return copyLarge(inputStream, outputStream, byteArray(bufferSize));
}
/**
* Copies bytes from an {@link InputStream} to chars on a
* {@link Writer} using the default character encoding of the platform.
* <p>
* This method buffers the input internally, so there is no need to use a
* {@link BufferedInputStream}.
* </p>
* <p>
* This method uses {@link InputStreamReader}.
* </p>
*
* @param input the {@link InputStream} to read
* @param writer the {@link Writer} to write to
* @throws NullPointerException if the input or output is null
* @throws IOException if an I/O error occurs
* @since 1.1
* @deprecated Use {@link #copy(InputStream, Writer, Charset)} instead
*/
@Deprecated
public static void copy(final InputStream input, final Writer writer)
throws IOException {
copy(input, writer, Charset.defaultCharset());
}
/**
* Copies bytes from an {@link InputStream} to chars on a
* {@link Writer} using the specified character encoding.
* <p>
* This method buffers the input internally, so there is no need to use a
* {@link BufferedInputStream}.
* </p>
* <p>
* This method uses {@link InputStreamReader}.
* </p>
*
* @param input the {@link InputStream} to read
* @param writer the {@link Writer} to write to
* @param inputCharset the charset to use for the input stream, null means platform default
* @throws NullPointerException if the input or output is null
* @throws IOException if an I/O error occurs
* @since 2.3
*/
public static void copy(final InputStream input, final Writer writer, final Charset inputCharset)
throws IOException {
copy(new InputStreamReader(input, Charsets.toCharset(inputCharset)), writer);
}
/**
* Copies bytes from an {@link InputStream} to chars on a
* {@link Writer} using the specified character encoding.
* <p>
* This method buffers the input internally, so there is no need to use a
* {@link BufferedInputStream}.
* </p>
* <p>
* Character encoding names can be found at
* <a href="https://www.iana.org/assignments/character-sets">IANA</a>.
* </p>
* <p>
* This method uses {@link InputStreamReader}.
* </p>
*
* @param input the {@link InputStream} to read
* @param writer the {@link Writer} to write to
* @param inputCharsetName the name of the requested charset for the InputStream, null means platform default
* @throws NullPointerException if the input or output is null
* @throws IOException if an I/O error occurs
* @throws java.nio.charset.UnsupportedCharsetException if the encoding is not supported
* @since 1.1
*/
public static void copy(final InputStream input, final Writer writer, final String inputCharsetName)
throws IOException {
copy(input, writer, Charsets.toCharset(inputCharsetName));
}
/**
* Copies bytes from a {@link ByteArrayOutputStream} to a {@link QueueInputStream}.
* <p>
* Unlike using JDK {@link PipedInputStream} and {@link PipedOutputStream} for this, this
* solution works safely in a single thread environment.
* </p>
* <p>
* Example usage:
* </p>
*
* <pre>
* ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
* outputStream.writeBytes("hello world".getBytes(StandardCharsets.UTF_8));
*
* InputStream inputStream = IOUtils.copy(outputStream);
* </pre>
*
* @param outputStream the {@link ByteArrayOutputStream} to read.
* @return the {@link QueueInputStream} filled with the content of the outputStream.
* @throws NullPointerException if the {@link ByteArrayOutputStream} is {@code null}.
* @throws IOException if an I/O error occurs.
* @since 2.12
*/
@SuppressWarnings("resource") // streams are closed by the caller.
public static QueueInputStream copy(final java.io.ByteArrayOutputStream outputStream) throws IOException {
Objects.requireNonNull(outputStream, "outputStream");
final QueueInputStream in = new QueueInputStream();
outputStream.writeTo(in.newQueueOutputStream());
return in;
}
/**
* Copies chars from a {@link Reader} to a {@link Appendable}.
* <p>
* This method buffers the input internally, so there is no need to use a
* {@link BufferedReader}.
* </p>
* <p>
* Large streams (over 2GB) will return a chars copied value of
* {@code -1} after the copy has completed since the correct
* number of chars cannot be returned as an int. For large streams
* use the {@link #copyLarge(Reader, Writer)} method.
* </p>
*
* @param reader the {@link Reader} to read
* @param output the {@link Appendable} to write to
* @return the number of characters copied, or -1 if > Integer.MAX_VALUE
* @throws NullPointerException if the input or output is null
* @throws IOException if an I/O error occurs
* @since 2.7
*/
public static long copy(final Reader reader, final Appendable output) throws IOException {
return copy(reader, output, CharBuffer.allocate(DEFAULT_BUFFER_SIZE));
}
/**
* Copies chars from a {@link Reader} to an {@link Appendable}.
* <p>
* This method uses the provided buffer, so there is no need to use a
* {@link BufferedReader}.
* </p>
*
* @param reader the {@link Reader} to read
* @param output the {@link Appendable} to write to
* @param buffer the buffer to be used for the copy
* @return the number of characters copied
* @throws NullPointerException if the input or output is null
* @throws IOException if an I/O error occurs
* @since 2.7
*/
public static long copy(final Reader reader, final Appendable output, final CharBuffer buffer) throws IOException {
long count = 0;
int n;
while (EOF != (n = reader.read(buffer))) {
buffer.flip();
output.append(buffer, 0, n);
count += n;
}
return count;
}
/**
* Copies chars from a {@link Reader} to bytes on an
* {@link OutputStream} using the default character encoding of the
* platform, and calling flush.
* <p>
* This method buffers the input internally, so there is no need to use a
* {@link BufferedReader}.
* </p>
* <p>
* Due to the implementation of OutputStreamWriter, this method performs a
* flush.
* </p>
* <p>
* This method uses {@link OutputStreamWriter}.
* </p>
*
* @param reader the {@link Reader} to read
* @param output the {@link OutputStream} to write to
* @throws NullPointerException if the input or output is null
* @throws IOException if an I/O error occurs
* @since 1.1
* @deprecated Use {@link #copy(Reader, OutputStream, Charset)} instead
*/
@Deprecated
public static void copy(final Reader reader, final OutputStream output)
throws IOException {
copy(reader, output, Charset.defaultCharset());
}
/**
* Copies chars from a {@link Reader} to bytes on an
* {@link OutputStream} using the specified character encoding, and
* calling flush.
* <p>
* This method buffers the input internally, so there is no need to use a
* {@link BufferedReader}.
* </p>
* <p>
* Due to the implementation of OutputStreamWriter, this method performs a
* flush.
* </p>
* <p>
* This method uses {@link OutputStreamWriter}.
* </p>
*
* @param reader the {@link Reader} to read
* @param output the {@link OutputStream} to write to
* @param outputCharset the charset to use for the OutputStream, null means platform default
* @throws NullPointerException if the input or output is null
* @throws IOException if an I/O error occurs
* @since 2.3
*/
public static void copy(final Reader reader, final OutputStream output, final Charset outputCharset)
throws IOException {
final OutputStreamWriter writer = new OutputStreamWriter(output, Charsets.toCharset(outputCharset));
copy(reader, writer);
// XXX Unless anyone is planning on rewriting OutputStreamWriter,
// we have to flush here.
writer.flush();
}
/**
* Copies chars from a {@link Reader} to bytes on an
* {@link OutputStream} using the specified character encoding, and
* calling flush.
* <p>
* This method buffers the input internally, so there is no need to use a
* {@link BufferedReader}.
* </p>
* <p>
* Character encoding names can be found at
* <a href="http://www.iana.org/assignments/character-sets">IANA</a>.
* </p>
* <p>
* Due to the implementation of OutputStreamWriter, this method performs a
* flush.
* </p>
* <p>
* This method uses {@link OutputStreamWriter}.
* </p>
*
* @param reader the {@link Reader} to read
* @param output the {@link OutputStream} to write to
* @param outputCharsetName the name of the requested charset for the OutputStream, null means platform default
* @throws NullPointerException if the input or output is null
* @throws IOException if an I/O error occurs
* @throws java.nio.charset.UnsupportedCharsetException if the encoding is not supported
* @since 1.1
*/
public static void copy(final Reader reader, final OutputStream output, final String outputCharsetName)
throws IOException {
copy(reader, output, Charsets.toCharset(outputCharsetName));
}
/**
* Copies chars from a {@link Reader} to a {@link Writer}.
* <p>
* This method buffers the input internally, so there is no need to use a
* {@link BufferedReader}.
* </p>
* <p>
* Large streams (over 2GB) will return a chars copied value of
* {@code -1} after the copy has completed since the correct
* number of chars cannot be returned as an int. For large streams
* use the {@link #copyLarge(Reader, Writer)} method.
* </p>
*
* @param reader the {@link Reader} to read.
* @param writer the {@link Writer} to write.
* @return the number of characters copied, or -1 if > Integer.MAX_VALUE
* @throws NullPointerException if the input or output is null
* @throws IOException if an I/O error occurs
* @since 1.1
*/
public static int copy(final Reader reader, final Writer writer) throws IOException {
final long count = copyLarge(reader, writer);
if (count > Integer.MAX_VALUE) {
return EOF;
}
return (int) count;
}
/**
* Copies bytes from a {@link URL} to an {@link OutputStream}.
* <p>
* This method buffers the input internally, so there is no need to use a {@link BufferedInputStream}.
* </p>
* <p>
* The buffer size is given by {@link #DEFAULT_BUFFER_SIZE}.
* </p>
*
* @param url the {@link URL} to read.
* @param file the {@link OutputStream} to write.
* @return the number of bytes copied.
* @throws NullPointerException if the URL is {@code null}.
* @throws NullPointerException if the OutputStream is {@code null}.
* @throws IOException if an I/O error occurs.
* @since 2.9.0
*/
public static long copy(final URL url, final File file) throws IOException {
try (OutputStream outputStream = Files.newOutputStream(Objects.requireNonNull(file, "file").toPath())) {
return copy(url, outputStream);
}
}
/**
* Copies bytes from a {@link URL} to an {@link OutputStream}.
* <p>
* This method buffers the input internally, so there is no need to use a {@link BufferedInputStream}.
* </p>
* <p>
* The buffer size is given by {@link #DEFAULT_BUFFER_SIZE}.
* </p>
*
* @param url the {@link URL} to read.
* @param outputStream the {@link OutputStream} to write.
* @return the number of bytes copied.
* @throws NullPointerException if the URL is {@code null}.
* @throws NullPointerException if the OutputStream is {@code null}.
* @throws IOException if an I/O error occurs.
* @since 2.9.0
*/
public static long copy(final URL url, final OutputStream outputStream) throws IOException {
try (InputStream inputStream = Objects.requireNonNull(url, "url").openStream()) {
return copyLarge(inputStream, outputStream);
}
}
/**
* Copies bytes from a large (over 2GB) {@link InputStream} to an
* {@link OutputStream}.
* <p>
* This method buffers the input internally, so there is no need to use a
* {@link BufferedInputStream}.
* </p>
* <p>
* The buffer size is given by {@link #DEFAULT_BUFFER_SIZE}.
* </p>
*
* @param inputStream the {@link InputStream} to read.
* @param outputStream the {@link OutputStream} to write.
* @return the number of bytes copied.
* @throws NullPointerException if the InputStream is {@code null}.
* @throws NullPointerException if the OutputStream is {@code null}.
* @throws IOException if an I/O error occurs.
* @since 1.3
*/
public static long copyLarge(final InputStream inputStream, final OutputStream outputStream)
throws IOException {
return copy(inputStream, outputStream, DEFAULT_BUFFER_SIZE);
}
/**
* Copies bytes from a large (over 2GB) {@link InputStream} to an
* {@link OutputStream}.
* <p>
* This method uses the provided buffer, so there is no need to use a
* {@link BufferedInputStream}.
* </p>
*
* @param inputStream the {@link InputStream} to read.
* @param outputStream the {@link OutputStream} to write.
* @param buffer the buffer to use for the copy
* @return the number of bytes copied.
* @throws NullPointerException if the InputStream is {@code null}.
* @throws NullPointerException if the OutputStream is {@code null}.
* @throws IOException if an I/O error occurs.
* @since 2.2
*/
@SuppressWarnings("resource") // streams are closed by the caller.
public static long copyLarge(final InputStream inputStream, final OutputStream outputStream, final byte[] buffer)
throws IOException {
Objects.requireNonNull(inputStream, "inputStream");
Objects.requireNonNull(outputStream, "outputStream");
long count = 0;
int n;
while (EOF != (n = inputStream.read(buffer))) {
outputStream.write(buffer, 0, n);
count += n;
}
return count;
}
/**
* Copies some or all bytes from a large (over 2GB) {@link InputStream} to an
* {@link OutputStream}, optionally skipping input bytes.
* <p>
* This method buffers the input internally, so there is no need to use a
* {@link BufferedInputStream}.
* </p>
* <p>
* Note that the implementation uses {@link #skip(InputStream, long)}.
* This means that the method may be considerably less efficient than using the actual skip implementation,
* this is done to guarantee that the correct number of characters are skipped.
* </p>
* The buffer size is given by {@link #DEFAULT_BUFFER_SIZE}.
*
* @param input the {@link InputStream} to read
* @param output the {@link OutputStream} to write to
* @param inputOffset : number of bytes to skip from input before copying
* -ve values are ignored
* @param length number of bytes to copy. -ve means all
* @return the number of bytes copied
* @throws NullPointerException if the input or output is null
* @throws IOException if an I/O error occurs
* @since 2.2
*/
public static long copyLarge(final InputStream input, final OutputStream output, final long inputOffset,
final long length) throws IOException {
return copyLarge(input, output, inputOffset, length, getScratchByteArray());
}
/**
* Copies some or all bytes from a large (over 2GB) {@link InputStream} to an
* {@link OutputStream}, optionally skipping input bytes.
* <p>
* This method uses the provided buffer, so there is no need to use a
* {@link BufferedInputStream}.
* </p>
* <p>
* Note that the implementation uses {@link #skip(InputStream, long)}.
* This means that the method may be considerably less efficient than using the actual skip implementation,
* this is done to guarantee that the correct number of characters are skipped.
* </p>
*
* @param input the {@link InputStream} to read
* @param output the {@link OutputStream} to write to
* @param inputOffset number of bytes to skip from input before copying
* -ve values are ignored
* @param length number of bytes to copy. -ve means all
* @param buffer the buffer to use for the copy
* @return the number of bytes copied
* @throws NullPointerException if the input or output is null
* @throws IOException if an I/O error occurs
* @since 2.2
*/
public static long copyLarge(final InputStream input, final OutputStream output,
final long inputOffset, final long length, final byte[] buffer) throws IOException {
if (inputOffset > 0) {
skipFully(input, inputOffset);
}
if (length == 0) {
return 0;
}
final int bufferLength = buffer.length;
int bytesToRead = bufferLength;
if (length > 0 && length < bufferLength) {
bytesToRead = (int) length;
}
int read;
long totalRead = 0;
while (bytesToRead > 0 && EOF != (read = input.read(buffer, 0, bytesToRead))) {
output.write(buffer, 0, read);
totalRead += read;
if (length > 0) { // only adjust length if not reading to the end
// Note the cast must work because buffer.length is an integer
bytesToRead = (int) Math.min(length - totalRead, bufferLength);
}
}
return totalRead;
}
/**
* Copies chars from a large (over 2GB) {@link Reader} to a {@link Writer}.
* <p>
* This method buffers the input internally, so there is no need to use a
* {@link BufferedReader}.
* </p>
* <p>
* The buffer size is given by {@link #DEFAULT_BUFFER_SIZE}.
* </p>
*
* @param reader the {@link Reader} to source.
* @param writer the {@link Writer} to target.
* @return the number of characters copied
* @throws NullPointerException if the input or output is null
* @throws IOException if an I/O error occurs
* @since 1.3
*/
public static long copyLarge(final Reader reader, final Writer writer) throws IOException {
return copyLarge(reader, writer, getScratchCharArray());
}
/**
* Copies chars from a large (over 2GB) {@link Reader} to a {@link Writer}.
* <p>
* This method uses the provided buffer, so there is no need to use a
* {@link BufferedReader}.
* </p>
*
* @param reader the {@link Reader} to source.
* @param writer the {@link Writer} to target.
* @param buffer the buffer to be used for the copy
* @return the number of characters copied
* @throws NullPointerException if the input or output is null
* @throws IOException if an I/O error occurs
* @since 2.2
*/
public static long copyLarge(final Reader reader, final Writer writer, final char[] buffer) throws IOException {
long count = 0;
int n;
while (EOF != (n = reader.read(buffer))) {
writer.write(buffer, 0, n);
count += n;
}
return count;
}
/**
* Copies some or all chars from a large (over 2GB) {@link InputStream} to an
* {@link OutputStream}, optionally skipping input chars.
* <p>
* This method buffers the input internally, so there is no need to use a
* {@link BufferedReader}.
* </p>
* <p>
* The buffer size is given by {@link #DEFAULT_BUFFER_SIZE}.
* </p>
*
* @param reader the {@link Reader} to read
* @param writer the {@link Writer} to write to
* @param inputOffset number of chars to skip from input before copying
* -ve values are ignored
* @param length number of chars to copy. -ve means all
* @return the number of chars copied
* @throws NullPointerException if the input or output is null
* @throws IOException if an I/O error occurs
* @since 2.2
*/
public static long copyLarge(final Reader reader, final Writer writer, final long inputOffset, final long length)
throws IOException {
return copyLarge(reader, writer, inputOffset, length, getScratchCharArray());
}
/**
* Copies some or all chars from a large (over 2GB) {@link InputStream} to an
* {@link OutputStream}, optionally skipping input chars.
* <p>
* This method uses the provided buffer, so there is no need to use a
* {@link BufferedReader}.
* </p>
*
* @param reader the {@link Reader} to read
* @param writer the {@link Writer} to write to
* @param inputOffset number of chars to skip from input before copying
* -ve values are ignored
* @param length number of chars to copy. -ve means all
* @param buffer the buffer to be used for the copy
* @return the number of chars copied
* @throws NullPointerException if the input or output is null
* @throws IOException if an I/O error occurs
* @since 2.2
*/
public static long copyLarge(final Reader reader, final Writer writer, final long inputOffset, final long length,
final char[] buffer)
throws IOException {
if (inputOffset > 0) {
skipFully(reader, inputOffset);
}
if (length == 0) {
return 0;
}
int bytesToRead = buffer.length;
if (length > 0 && length < buffer.length) {
bytesToRead = (int) length;
}
int read;
long totalRead = 0;
while (bytesToRead > 0 && EOF != (read = reader.read(buffer, 0, bytesToRead))) {
writer.write(buffer, 0, read);
totalRead += read;
if (length > 0) { // only adjust length if not reading to the end
// Note the cast must work because buffer.length is an integer
bytesToRead = (int) Math.min(length - totalRead, buffer.length);
}
}
return totalRead;
}
/**
* Fills the given array with 0s.
*
* @param arr The non-null array to fill.
* @return The given array.
*/
private static byte[] fill0(final byte[] arr) {
Arrays.fill(arr, (byte) 0);
return arr;
}
/**
* Fills the given array with 0s.
*
* @param arr The non-null array to fill.
* @return The given array.
*/
private static char[] fill0(final char[] arr) {
Arrays.fill(arr, (char) 0);
return arr;
}
/**
* Gets the internal byte array buffer, intended for both reading and writing.
*
* @return the internal byte array buffer, intended for both reading and writing.
*/
static byte[] getScratchByteArray() {
return fill0(SCRATCH_BYTE_BUFFER_RW.get());
}
/**
* Gets the internal byte array intended for write only operations.
*
* @return the internal byte array intended for write only operations.
*/
static byte[] getScratchByteArrayWriteOnly() {
return fill0(SCRATCH_BYTE_BUFFER_WO);
}
/**
* Gets the char byte array buffer, intended for both reading and writing.
*
* @return the char byte array buffer, intended for both reading and writing.
*/
static char[] getScratchCharArray() {
return fill0(SCRATCH_CHAR_BUFFER_RW.get());
}
/**
* Gets the internal char array intended for write only operations.
*
* @return the internal char array intended for write only operations.
*/
static char[] getScratchCharArrayWriteOnly() {
return fill0(SCRATCH_CHAR_BUFFER_WO);
}
/**
* Returns the length of the given array in a null-safe manner.
*
* @param array an array or null
* @return the array length, or 0 if the given array is null.
* @since 2.7
*/
public static int length(final byte[] array) {
return array == null ? 0 : array.length;
}
/**
* Returns the length of the given array in a null-safe manner.
*
* @param array an array or null
* @return the array length, or 0 if the given array is null.
* @since 2.7
*/
public static int length(final char[] array) {
return array == null ? 0 : array.length;
}
/**
* Returns the length of the given CharSequence in a null-safe manner.
*
* @param csq a CharSequence or null
* @return the CharSequence length, or 0 if the given CharSequence is null.
* @since 2.7
*/
public static int length(final CharSequence csq) {
return csq == null ? 0 : csq.length();
}
/**
* Returns the length of the given array in a null-safe manner.
*
* @param array an array or null
* @return the array length, or 0 if the given array is null.
* @since 2.7
*/
public static int length(final Object[] array) {
return array == null ? 0 : array.length;
}
/**
* Returns an Iterator for the lines in an {@link InputStream}, using
* the character encoding specified (or default encoding if null).
* <p>
* {@link LineIterator} holds a reference to the open
* {@link InputStream} specified here. When you have finished with
* the iterator you should close the stream to free internal resources.
* This can be done by using a try-with-resources block, closing the stream directly, or by calling
* {@link LineIterator#close()}.
* </p>
* <p>
* The recommended usage pattern is:
* </p>
* <pre>
* try {
* LineIterator it = IOUtils.lineIterator(stream, charset);
* while (it.hasNext()) {
* String line = it.nextLine();
* /// do something with line
* }
* } finally {
* IOUtils.closeQuietly(stream);
* }
* </pre>
*
* @param input the {@link InputStream} to read, not null
* @param charset the charset to use, null means platform default
* @return an Iterator of the lines in the reader, never null
* @throws IllegalArgumentException if the input is null
* @since 2.3
*/
public static LineIterator lineIterator(final InputStream input, final Charset charset) {
return new LineIterator(new InputStreamReader(input, Charsets.toCharset(charset)));
}
/**
* Returns an Iterator for the lines in an {@link InputStream}, using
* the character encoding specified (or default encoding if null).
* <p>
* {@link LineIterator} holds a reference to the open
* {@link InputStream} specified here. When you have finished with
* the iterator you should close the stream to free internal resources.
* This can be done by using a try-with-resources block, closing the stream directly, or by calling
* {@link LineIterator#close()}.
* </p>
* <p>
* The recommended usage pattern is:
* </p>
* <pre>
* try {
* LineIterator it = IOUtils.lineIterator(stream, StandardCharsets.UTF_8.name());
* while (it.hasNext()) {
* String line = it.nextLine();
* /// do something with line
* }
* } finally {
* IOUtils.closeQuietly(stream);
* }
* </pre>
*
* @param input the {@link InputStream} to read, not null
* @param charsetName the encoding to use, null means platform default
* @return an Iterator of the lines in the reader, never null
* @throws IllegalArgumentException if the input is null
* @throws java.nio.charset.UnsupportedCharsetException if the encoding is not supported
* @since 1.2
*/
public static LineIterator lineIterator(final InputStream input, final String charsetName) {
return lineIterator(input, Charsets.toCharset(charsetName));
}
/**
* Returns an Iterator for the lines in a {@link Reader}.
* <p>
* {@link LineIterator} holds a reference to the open
* {@link Reader} specified here. When you have finished with the
* iterator you should close the reader to free internal resources.
* This can be done by using a try-with-resources block, closing the reader directly, or by calling
* {@link LineIterator#close()}.
* </p>
* <p>
* The recommended usage pattern is:
* </p>
* <pre>
* try {
* LineIterator it = IOUtils.lineIterator(reader);
* while (it.hasNext()) {
* String line = it.nextLine();
* /// do something with line
* }
* } finally {
* IOUtils.closeQuietly(reader);
* }
* </pre>
*
* @param reader the {@link Reader} to read, not null
* @return an Iterator of the lines in the reader, never null
* @throws NullPointerException if the reader is null
* @since 1.2
*/
public static LineIterator lineIterator(final Reader reader) {
return new LineIterator(reader);
}
/**
* Reads bytes from an input stream.
* This implementation guarantees that it will read as many bytes
* as possible before giving up; this may not always be the case for
* subclasses of {@link InputStream}.
*
* @param input where to read input from
* @param buffer destination
* @return actual length read; may be less than requested if EOF was reached
* @throws IOException if a read error occurs
* @since 2.2
*/
public static int read(final InputStream input, final byte[] buffer) throws IOException {
return read(input, buffer, 0, buffer.length);
}
/**
* Reads bytes from an input stream.
* This implementation guarantees that it will read as many bytes
* as possible before giving up; this may not always be the case for
* subclasses of {@link InputStream}.
*
* @param input where to read input
* @param buffer destination
* @param offset initial offset into buffer
* @param length length to read, must be >= 0
* @return actual length read; may be less than requested if EOF was reached
* @throws IllegalArgumentException if length is negative
* @throws IOException if a read error occurs
* @since 2.2
*/
public static int read(final InputStream input, final byte[] buffer, final int offset, final int length)
throws IOException {
if (length == 0) {
return 0;
}
return read(input::read, buffer, offset, length);
}
/**
* Reads bytes from an input. This implementation guarantees that it will read as many bytes as possible before giving up; this may not always be the case
* for subclasses of {@link InputStream}.
*
* @param input How to read input
* @param buffer destination
* @param offset initial offset into buffer
* @param length length to read, must be >= 0
* @return actual length read; may be less than requested if EOF was reached
* @throws IllegalArgumentException if length is negative
* @throws IOException if a read error occurs
* @since 2.2
*/
static int read(final IOTriFunction<byte[], Integer, Integer, Integer> input, final byte[] buffer, final int offset, final int length)
throws IOException {
if (length < 0) {
throw new IllegalArgumentException("Length must not be negative: " + length);
}
int remaining = length;
while (remaining > 0) {
final int location = length - remaining;
final int count = input.apply(buffer, offset + location, remaining);
if (EOF == count) {
break;
}
remaining -= count;
}
return length - remaining;
}
/**
* Reads bytes from a ReadableByteChannel.
* <p>
* This implementation guarantees that it will read as many bytes
* as possible before giving up; this may not always be the case for
* subclasses of {@link ReadableByteChannel}.
* </p>
*
* @param input the byte channel to read
* @param buffer byte buffer destination
* @return the actual length read; may be less than requested if EOF was reached
* @throws IOException if a read error occurs
* @since 2.5
*/
public static int read(final ReadableByteChannel input, final ByteBuffer buffer) throws IOException {
final int length = buffer.remaining();
while (buffer.remaining() > 0) {
final int count = input.read(buffer);
if (EOF == count) { // EOF
break;
}
}
return length - buffer.remaining();
}
/**
* Reads characters from an input character stream.
* This implementation guarantees that it will read as many characters
* as possible before giving up; this may not always be the case for
* subclasses of {@link Reader}.
*
* @param reader where to read input from
* @param buffer destination
* @return actual length read; may be less than requested if EOF was reached
* @throws IOException if a read error occurs
* @since 2.2
*/
public static int read(final Reader reader, final char[] buffer) throws IOException {
return read(reader, buffer, 0, buffer.length);
}
/**
* Reads characters from an input character stream.
* This implementation guarantees that it will read as many characters
* as possible before giving up; this may not always be the case for
* subclasses of {@link Reader}.
*
* @param reader where to read input from
* @param buffer destination
* @param offset initial offset into buffer
* @param length length to read, must be >= 0
* @return actual length read; may be less than requested if EOF was reached
* @throws IllegalArgumentException if length is negative
* @throws IOException if a read error occurs
* @since 2.2
*/
public static int read(final Reader reader, final char[] buffer, final int offset, final int length)
throws IOException {
if (length < 0) {
throw new IllegalArgumentException("Length must not be negative: " + length);
}
int remaining = length;
while (remaining > 0) {
final int location = length - remaining;
final int count = reader.read(buffer, offset + location, remaining);
if (EOF == count) { // EOF
break;
}
remaining -= count;
}
return length - remaining;
}
/**
* Reads the requested number of bytes or fail if there are not enough left.
* <p>
* This allows for the possibility that {@link InputStream#read(byte[], int, int)} may
* not read as many bytes as requested (most likely because of reaching EOF).
* </p>
*
* @param input where to read input from
* @param buffer destination
*
* @throws IOException if there is a problem reading the file
* @throws IllegalArgumentException if length is negative
* @throws EOFException if the number of bytes read was incorrect
* @since 2.2
*/
public static void readFully(final InputStream input, final byte[] buffer) throws IOException {
readFully(input, buffer, 0, buffer.length);
}
/**
* Reads the requested number of bytes or fail if there are not enough left.
* <p>
* This allows for the possibility that {@link InputStream#read(byte[], int, int)} may
* not read as many bytes as requested (most likely because of reaching EOF).
* </p>
*
* @param input where to read input from
* @param buffer destination
* @param offset initial offset into buffer
* @param length length to read, must be >= 0
*
* @throws IOException if there is a problem reading the file
* @throws IllegalArgumentException if length is negative
* @throws EOFException if the number of bytes read was incorrect
* @since 2.2
*/
public static void readFully(final InputStream input, final byte[] buffer, final int offset, final int length)
throws IOException {
final int actual = read(input, buffer, offset, length);
if (actual != length) {
throw new EOFException("Length to read: " + length + " actual: " + actual);
}
}
/**
* Reads the requested number of bytes or fail if there are not enough left.
* <p>
* This allows for the possibility that {@link InputStream#read(byte[], int, int)} may
* not read as many bytes as requested (most likely because of reaching EOF).
* </p>
*
* @param input where to read input from
* @param length length to read, must be >= 0
* @return the bytes read from input
* @throws IOException if there is a problem reading the file
* @throws IllegalArgumentException if length is negative
* @throws EOFException if the number of bytes read was incorrect
* @since 2.5
*/
public static byte[] readFully(final InputStream input, final int length) throws IOException {
final byte[] buffer = byteArray(length);
readFully(input, buffer, 0, buffer.length);
return buffer;
}
/**
* Reads the requested number of bytes or fail if there are not enough left.
* <p>
* This allows for the possibility that {@link ReadableByteChannel#read(ByteBuffer)} may
* not read as many bytes as requested (most likely because of reaching EOF).
* </p>
*
* @param input the byte channel to read
* @param buffer byte buffer destination
* @throws IOException if there is a problem reading the file
* @throws EOFException if the number of bytes read was incorrect
* @since 2.5
*/
public static void readFully(final ReadableByteChannel input, final ByteBuffer buffer) throws IOException {
final int expected = buffer.remaining();
final int actual = read(input, buffer);
if (actual != expected) {
throw new EOFException("Length to read: " + expected + " actual: " + actual);
}
}
/**
* Reads the requested number of characters or fail if there are not enough left.
* <p>
* This allows for the possibility that {@link Reader#read(char[], int, int)} may
* not read as many characters as requested (most likely because of reaching EOF).
* </p>
*
* @param reader where to read input from
* @param buffer destination
* @throws IOException if there is a problem reading the file
* @throws IllegalArgumentException if length is negative
* @throws EOFException if the number of characters read was incorrect
* @since 2.2
*/
public static void readFully(final Reader reader, final char[] buffer) throws IOException {
readFully(reader, buffer, 0, buffer.length);
}
/**
* Reads the requested number of characters or fail if there are not enough left.
* <p>
* This allows for the possibility that {@link Reader#read(char[], int, int)} may
* not read as many characters as requested (most likely because of reaching EOF).
* </p>
*
* @param reader where to read input from
* @param buffer destination
* @param offset initial offset into buffer
* @param length length to read, must be >= 0
* @throws IOException if there is a problem reading the file
* @throws IllegalArgumentException if length is negative
* @throws EOFException if the number of characters read was incorrect
* @since 2.2
*/
public static void readFully(final Reader reader, final char[] buffer, final int offset, final int length)
throws IOException {
final int actual = read(reader, buffer, offset, length);
if (actual != length) {
throw new EOFException("Length to read: " + length + " actual: " + actual);
}
}
/**
* Gets the contents of a {@link CharSequence} as a list of Strings, one entry per line.
*
* @param csq the {@link CharSequence} to read, not null
* @return the list of Strings, never null
* @throws UncheckedIOException if an I/O error occurs
* @since 2.18.0
*/
public static List<String> readLines(final CharSequence csq) throws UncheckedIOException {
try (CharSequenceReader reader = new CharSequenceReader(csq)) {
return readLines(reader);
}
}
/**
* Gets the contents of an {@link InputStream} as a list of Strings,
* one entry per line, using the default character encoding of the platform.
* <p>
* This method buffers the input internally, so there is no need to use a
* {@link BufferedInputStream}.
* </p>
*
* @param input the {@link InputStream} to read, not null
* @return the list of Strings, never null
* @throws NullPointerException if the input is null
* @throws UncheckedIOException if an I/O error occurs
* @since 1.1
* @deprecated Use {@link #readLines(InputStream, Charset)} instead
*/
@Deprecated
public static List<String> readLines(final InputStream input) throws UncheckedIOException {
return readLines(input, Charset.defaultCharset());
}
/**
* Gets the contents of an {@link InputStream} as a list of Strings,
* one entry per line, using the specified character encoding.
* <p>
* This method buffers the input internally, so there is no need to use a
* {@link BufferedInputStream}.
* </p>
*
* @param input the {@link InputStream} to read, not null
* @param charset the charset to use, null means platform default
* @return the list of Strings, never null
* @throws NullPointerException if the input is null
* @throws UncheckedIOException if an I/O error occurs
* @since 2.3
*/
public static List<String> readLines(final InputStream input, final Charset charset) throws UncheckedIOException {
return readLines(new InputStreamReader(input, Charsets.toCharset(charset)));
}
/**
* Gets the contents of an {@link InputStream} as a list of Strings,
* one entry per line, using the specified character encoding.
* <p>
* Character encoding names can be found at
* <a href="http://www.iana.org/assignments/character-sets">IANA</a>.
* </p>
* <p>
* This method buffers the input internally, so there is no need to use a
* {@link BufferedInputStream}.
* </p>
*
* @param input the {@link InputStream} to read, not null
* @param charsetName the name of the requested charset, null means platform default
* @return the list of Strings, never null
* @throws NullPointerException if the input is null
* @throws UncheckedIOException if an I/O error occurs
* @throws java.nio.charset.UnsupportedCharsetException if the encoding is not supported
* @since 1.1
*/
public static List<String> readLines(final InputStream input, final String charsetName) throws UncheckedIOException {
return readLines(input, Charsets.toCharset(charsetName));
}
/**
* Gets the contents of a {@link Reader} as a list of Strings,
* one entry per line.
* <p>
* This method buffers the input internally, so there is no need to use a
* {@link BufferedReader}.
* </p>
*
* @param reader the {@link Reader} to read, not null
* @return the list of Strings, never null
* @throws NullPointerException if the input is null
* @throws UncheckedIOException if an I/O error occurs
* @since 1.1
*/
@SuppressWarnings("resource") // reader wraps input and is the responsibility of the caller.
public static List<String> readLines(final Reader reader) throws UncheckedIOException {
return toBufferedReader(reader).lines().collect(Collectors.toList());
}
/**
* Gets the contents of a resource as a byte array.
* <p>
* Delegates to {@link #resourceToByteArray(String, ClassLoader) resourceToByteArray(String, null)}.
* </p>
*
* @param name The resource name.
* @return the requested byte array
* @throws IOException if an I/O error occurs or the resource is not found.
* @see #resourceToByteArray(String, ClassLoader)
* @since 2.6
*/
public static byte[] resourceToByteArray(final String name) throws IOException {
return resourceToByteArray(name, null);
}
/**
* Gets the contents of a resource as a byte array.
* <p>
* Delegates to {@link #resourceToURL(String, ClassLoader)}.
* </p>
*
* @param name The resource name.
* @param classLoader the class loader that the resolution of the resource is delegated to
* @return the requested byte array
* @throws IOException if an I/O error occurs or the resource is not found.
* @see #resourceToURL(String, ClassLoader)
* @since 2.6
*/
public static byte[] resourceToByteArray(final String name, final ClassLoader classLoader) throws IOException {
return toByteArray(resourceToURL(name, classLoader));
}
/**
* Gets the contents of a resource as a String using the specified character encoding.
* <p>
* Delegates to {@link #resourceToString(String, Charset, ClassLoader) resourceToString(String, Charset, null)}.
* </p>
*
* @param name The resource name.
* @param charset the charset to use, null means platform default
* @return the requested String
* @throws IOException if an I/O error occurs or the resource is not found.
* @see #resourceToString(String, Charset, ClassLoader)
* @since 2.6
*/
public static String resourceToString(final String name, final Charset charset) throws IOException {
return resourceToString(name, charset, null);
}
/**
* Gets the contents of a resource as a String using the specified character encoding.
* <p>
* Delegates to {@link #resourceToURL(String, ClassLoader)}.
* </p>
*
* @param name The resource name.
* @param charset the Charset to use, null means platform default
* @param classLoader the class loader that the resolution of the resource is delegated to
* @return the requested String
* @throws IOException if an I/O error occurs.
* @see #resourceToURL(String, ClassLoader)
* @since 2.6
*/
public static String resourceToString(final String name, final Charset charset, final ClassLoader classLoader) throws IOException {
return toString(resourceToURL(name, classLoader), charset);
}
/**
* Gets a URL pointing to the given resource.
* <p>
* Delegates to {@link #resourceToURL(String, ClassLoader) resourceToURL(String, null)}.
* </p>
*
* @param name The resource name.
* @return A URL object for reading the resource.
* @throws IOException if the resource is not found.
* @since 2.6
*/
public static URL resourceToURL(final String name) throws IOException {
return resourceToURL(name, null);
}
/**
* Gets a URL pointing to the given resource.
* <p>
* If the {@code classLoader} is not null, call {@link ClassLoader#getResource(String)}, otherwise call
* {@link Class#getResource(String) IOUtils.class.getResource(name)}.
* </p>
*
* @param name The resource name.
* @param classLoader Delegate to this class loader if not null
* @return A URL object for reading the resource.
* @throws IOException if the resource is not found.
* @since 2.6
*/
public static URL resourceToURL(final String name, final ClassLoader classLoader) throws IOException {
// What about the thread context class loader?
// What about the system class loader?
final URL resource = classLoader == null ? IOUtils.class.getResource(name) : classLoader.getResource(name);
if (resource == null) {
throw new IOException("Resource not found: " + name);
}
return resource;
}
/**
* Skips bytes from an input byte stream.
* This implementation guarantees that it will read as many bytes
* as possible before giving up; this may not always be the case for
* skip() implementations in subclasses of {@link InputStream}.
* <p>
* Note that the implementation uses {@link InputStream#read(byte[], int, int)} rather
* than delegating to {@link InputStream#skip(long)}.
* This means that the method may be considerably less efficient than using the actual skip implementation,
* this is done to guarantee that the correct number of bytes are skipped.
* </p>
*
* @param input byte stream to skip
* @param skip number of bytes to skip.
* @return number of bytes actually skipped.
* @throws IOException if there is a problem reading the file
* @throws IllegalArgumentException if toSkip is negative
* @see InputStream#skip(long)
* @see <a href="https://issues.apache.org/jira/browse/IO-203">IO-203 - Add skipFully() method for InputStreams</a>
* @since 2.0
*/
public static long skip(final InputStream input, final long skip) throws IOException {
return skip(input, skip, IOUtils::getScratchByteArrayWriteOnly);
}
/**
* Skips bytes from an input byte stream.
* <p>
* Intended for special cases when customization of the temporary buffer is needed because, for example, a nested input stream has requirements for the
* bytes read. For example, when using {@link InflaterInputStream}s from multiple threads.
* </p>
* <p>
* This implementation guarantees that it will read as many bytes as possible before giving up; this may not always be the case for skip() implementations
* in subclasses of {@link InputStream}.
* </p>
* <p>
* Note that the implementation uses {@link InputStream#read(byte[], int, int)} rather than delegating to {@link InputStream#skip(long)}. This means that
* the method may be considerably less efficient than using the actual skip implementation, this is done to guarantee that the correct number of bytes are
* skipped.
* </p>
*
* @param input byte stream to skip
* @param skip number of bytes to skip.
* @param skipBufferSupplier Supplies the buffer to use for reading.
* @return number of bytes actually skipped.
* @throws IOException if there is a problem reading the file
* @throws IllegalArgumentException if toSkip is negative
* @see InputStream#skip(long)
* @see <a href="https://issues.apache.org/jira/browse/IO-203">IO-203 - Add skipFully() method for InputStreams</a>
* @since 2.14.0
*/
public static long skip(final InputStream input, final long skip, final Supplier<byte[]> skipBufferSupplier) throws IOException {
if (skip < 0) {
throw new IllegalArgumentException("Skip count must be non-negative, actual: " + skip);
}
//
// No need to synchronize access to SCRATCH_BYTE_BUFFER_WO: We don't care if the buffer is written multiple
// times or in parallel since the data is ignored. We reuse the same buffer, if the buffer size were variable or read-write,
// we would need to synch or use a thread local to ensure some other thread safety.
//
long remain = skip;
while (remain > 0) {
final byte[] skipBuffer = skipBufferSupplier.get();
// See https://issues.apache.org/jira/browse/IO-203 for why we use read() rather than delegating to skip()
final long n = input.read(skipBuffer, 0, (int) Math.min(remain, skipBuffer.length));
if (n < 0) { // EOF
break;
}
remain -= n;
}
return skip - remain;
}
/**
* Skips bytes from a ReadableByteChannel.
* This implementation guarantees that it will read as many bytes
* as possible before giving up.
*
* @param input ReadableByteChannel to skip
* @param toSkip number of bytes to skip.
* @return number of bytes actually skipped.
* @throws IOException if there is a problem reading the ReadableByteChannel
* @throws IllegalArgumentException if toSkip is negative
* @since 2.5
*/
public static long skip(final ReadableByteChannel input, final long toSkip) throws IOException {
if (toSkip < 0) {
throw new IllegalArgumentException("Skip count must be non-negative, actual: " + toSkip);
}
final ByteBuffer skipByteBuffer = ByteBuffer.allocate((int) Math.min(toSkip, DEFAULT_BUFFER_SIZE));
long remain = toSkip;
while (remain > 0) {
skipByteBuffer.position(0);
skipByteBuffer.limit((int) Math.min(remain, DEFAULT_BUFFER_SIZE));
final int n = input.read(skipByteBuffer);
if (n == EOF) {
break;
}
remain -= n;
}
return toSkip - remain;
}
/**
* Skips characters from an input character stream.
* This implementation guarantees that it will read as many characters
* as possible before giving up; this may not always be the case for
* skip() implementations in subclasses of {@link Reader}.
* <p>
* Note that the implementation uses {@link Reader#read(char[], int, int)} rather
* than delegating to {@link Reader#skip(long)}.
* This means that the method may be considerably less efficient than using the actual skip implementation,
* this is done to guarantee that the correct number of characters are skipped.
* </p>
*
* @param reader character stream to skip
* @param toSkip number of characters to skip.
* @return number of characters actually skipped.
* @throws IOException if there is a problem reading the file
* @throws IllegalArgumentException if toSkip is negative
* @see Reader#skip(long)
* @see <a href="https://issues.apache.org/jira/browse/IO-203">IO-203 - Add skipFully() method for InputStreams</a>
* @since 2.0
*/
public static long skip(final Reader reader, final long toSkip) throws IOException {
if (toSkip < 0) {
throw new IllegalArgumentException("Skip count must be non-negative, actual: " + toSkip);
}
long remain = toSkip;
while (remain > 0) {
// See https://issues.apache.org/jira/browse/IO-203 for why we use read() rather than delegating to skip()
final char[] charArray = getScratchCharArrayWriteOnly();
final long n = reader.read(charArray, 0, (int) Math.min(remain, charArray.length));
if (n < 0) { // EOF
break;
}
remain -= n;
}
return toSkip - remain;
}
/**
* Skips the requested number of bytes or fail if there are not enough left.
* <p>
* This allows for the possibility that {@link InputStream#skip(long)} may
* not skip as many bytes as requested (most likely because of reaching EOF).
* </p>
* <p>
* Note that the implementation uses {@link #skip(InputStream, long)}.
* This means that the method may be considerably less efficient than using the actual skip implementation,
* this is done to guarantee that the correct number of characters are skipped.
* </p>
*
* @param input stream to skip
* @param toSkip the number of bytes to skip
* @throws IOException if there is a problem reading the file
* @throws IllegalArgumentException if toSkip is negative
* @throws EOFException if the number of bytes skipped was incorrect
* @see InputStream#skip(long)
* @since 2.0
*/
public static void skipFully(final InputStream input, final long toSkip) throws IOException {
final long skipped = skip(input, toSkip, IOUtils::getScratchByteArrayWriteOnly);
if (skipped != toSkip) {
throw new EOFException("Bytes to skip: " + toSkip + " actual: " + skipped);
}
}
/**
* Skips the requested number of bytes or fail if there are not enough left.
* <p>
* Intended for special cases when customization of the temporary buffer is needed because, for example, a nested input stream has requirements for the
* bytes read. For example, when using {@link InflaterInputStream}s from multiple threads.
* </p>
* <p>
* This allows for the possibility that {@link InputStream#skip(long)} may not skip as many bytes as requested (most likely because of reaching EOF).
* </p>
* <p>
* Note that the implementation uses {@link #skip(InputStream, long)}. This means that the method may be considerably less efficient than using the actual
* skip implementation, this is done to guarantee that the correct number of characters are skipped.
* </p>
*
* @param input stream to skip
* @param toSkip the number of bytes to skip
* @param skipBufferSupplier Supplies the buffer to use for reading.
* @throws IOException if there is a problem reading the file
* @throws IllegalArgumentException if toSkip is negative
* @throws EOFException if the number of bytes skipped was incorrect
* @see InputStream#skip(long)
* @since 2.14.0
*/
public static void skipFully(final InputStream input, final long toSkip, final Supplier<byte[]> skipBufferSupplier) throws IOException {
if (toSkip < 0) {
throw new IllegalArgumentException("Bytes to skip must not be negative: " + toSkip);
}
final long skipped = skip(input, toSkip, skipBufferSupplier);
if (skipped != toSkip) {
throw new EOFException("Bytes to skip: " + toSkip + " actual: " + skipped);
}
}
/**
* Skips the requested number of bytes or fail if there are not enough left.
*
* @param input ReadableByteChannel to skip
* @param toSkip the number of bytes to skip
* @throws IOException if there is a problem reading the ReadableByteChannel
* @throws IllegalArgumentException if toSkip is negative
* @throws EOFException if the number of bytes skipped was incorrect
* @since 2.5
*/
public static void skipFully(final ReadableByteChannel input, final long toSkip) throws IOException {
if (toSkip < 0) {
throw new IllegalArgumentException("Bytes to skip must not be negative: " + toSkip);
}
final long skipped = skip(input, toSkip);
if (skipped != toSkip) {
throw new EOFException("Bytes to skip: " + toSkip + " actual: " + skipped);
}
}
/**
* Skips the requested number of characters or fail if there are not enough left.
* <p>
* This allows for the possibility that {@link Reader#skip(long)} may
* not skip as many characters as requested (most likely because of reaching EOF).
* </p>
* <p>
* Note that the implementation uses {@link #skip(Reader, long)}.
* This means that the method may be considerably less efficient than using the actual skip implementation,
* this is done to guarantee that the correct number of characters are skipped.
* </p>
*
* @param reader stream to skip
* @param toSkip the number of characters to skip
* @throws IOException if there is a problem reading the file
* @throws IllegalArgumentException if toSkip is negative
* @throws EOFException if the number of characters skipped was incorrect
* @see Reader#skip(long)
* @since 2.0
*/
public static void skipFully(final Reader reader, final long toSkip) throws IOException {
final long skipped = skip(reader, toSkip);
if (skipped != toSkip) {
throw new EOFException("Chars to skip: " + toSkip + " actual: " + skipped);
}
}
/**
* Fetches entire contents of an {@link InputStream} and represent
* same data as result InputStream.
* <p>
* This method is useful where,
* </p>
* <ul>
* <li>Source InputStream is slow.</li>
* <li>It has network resources associated, so we cannot keep it open for
* long time.</li>
* <li>It has network timeout associated.</li>
* </ul>
* <p>
* It can be used in favor of {@link #toByteArray(InputStream)}, since it
* avoids unnecessary allocation and copy of byte[].<br>
* This method buffers the input internally, so there is no need to use a
* {@link BufferedInputStream}.
* </p>
*
* @param input Stream to be fully buffered.
* @return A fully buffered stream.
* @throws IOException if an I/O error occurs.
* @since 2.0
*/
public static InputStream toBufferedInputStream(final InputStream input) throws IOException {
return ByteArrayOutputStream.toBufferedInputStream(input);
}
/**
* Fetches entire contents of an {@link InputStream} and represent
* same data as result InputStream.
* <p>
* This method is useful where,
* </p>
* <ul>
* <li>Source InputStream is slow.</li>
* <li>It has network resources associated, so we cannot keep it open for
* long time.</li>
* <li>It has network timeout associated.</li>
* </ul>
* <p>
* It can be used in favor of {@link #toByteArray(InputStream)}, since it
* avoids unnecessary allocation and copy of byte[].<br>
* This method buffers the input internally, so there is no need to use a
* {@link BufferedInputStream}.
* </p>
*
* @param input Stream to be fully buffered.
* @param size the initial buffer size
* @return A fully buffered stream.
* @throws IOException if an I/O error occurs.
* @since 2.5
*/
public static InputStream toBufferedInputStream(final InputStream input, final int size) throws IOException {
return ByteArrayOutputStream.toBufferedInputStream(input, size);
}
/**
* Returns the given reader if it is a {@link BufferedReader}, otherwise creates a BufferedReader from the given
* reader.
*
* @param reader the reader to wrap or return (not null)
* @return the given reader or a new {@link BufferedReader} for the given reader
* @throws NullPointerException if the input parameter is null
* @see #buffer(Reader)
* @since 2.2
*/
public static BufferedReader toBufferedReader(final Reader reader) {
return reader instanceof BufferedReader ? (BufferedReader) reader : new BufferedReader(reader);
}
/**
* Returns the given reader if it is a {@link BufferedReader}, otherwise creates a BufferedReader from the given
* reader.
*
* @param reader the reader to wrap or return (not null)
* @param size the buffer size, if a new BufferedReader is created.
* @return the given reader or a new {@link BufferedReader} for the given reader
* @throws NullPointerException if the input parameter is null
* @see #buffer(Reader)
* @since 2.5
*/
public static BufferedReader toBufferedReader(final Reader reader, final int size) {
return reader instanceof BufferedReader ? (BufferedReader) reader : new BufferedReader(reader, size);
}
/**
* Gets the contents of an {@link InputStream} as a {@code byte[]}.
* <p>
* This method buffers the input internally, so there is no need to use a
* {@link BufferedInputStream}.
* </p>
*
* @param inputStream the {@link InputStream} to read.
* @return the requested byte array.
* @throws NullPointerException if the InputStream is {@code null}.
* @throws IOException if an I/O error occurs or reading more than {@link Integer#MAX_VALUE} occurs.
*/
public static byte[] toByteArray(final InputStream inputStream) throws IOException {
// We use a ThresholdingOutputStream to avoid reading AND writing more than Integer.MAX_VALUE.
try (UnsynchronizedByteArrayOutputStream ubaOutput = UnsynchronizedByteArrayOutputStream.builder().get();
ThresholdingOutputStream thresholdOutput = new ThresholdingOutputStream(Integer.MAX_VALUE, os -> {
throw new IllegalArgumentException(String.format("Cannot read more than %,d into a byte array", Integer.MAX_VALUE));
}, os -> ubaOutput)) {
copy(inputStream, thresholdOutput);
return ubaOutput.toByteArray();
}
}
/**
* Gets the contents of an {@link InputStream} as a {@code byte[]}. Use this method instead of
* {@link #toByteArray(InputStream)} when {@link InputStream} size is known.
*
* @param input the {@link InputStream} to read.
* @param size the size of {@link InputStream} to read, where 0 < {@code size} <= length of input stream.
* @return byte [] of length {@code size}.
* @throws IOException if an I/O error occurs or {@link InputStream} length is smaller than parameter {@code size}.
* @throws IllegalArgumentException if {@code size} is less than zero.
* @since 2.1
*/
public static byte[] toByteArray(final InputStream input, final int size) throws IOException {
if (size == 0) {
return EMPTY_BYTE_ARRAY;
}
return toByteArray(Objects.requireNonNull(input, "input")::read, size);
}
/**
* Gets contents of an {@link InputStream} as a {@code byte[]}.
* Use this method instead of {@link #toByteArray(InputStream)}
* when {@link InputStream} size is known.
* <strong>NOTE:</strong> the method checks that the length can safely be cast to an int without truncation
* before using {@link IOUtils#toByteArray(InputStream, int)} to read into the byte array.
* (Arrays can have no more than Integer.MAX_VALUE entries anyway)
*
* @param input the {@link InputStream} to read
* @param size the size of {@link InputStream} to read, where 0 < {@code size} <= min(Integer.MAX_VALUE, length of input stream).
* @return byte [] the requested byte array, of length {@code size}
* @throws IOException if an I/O error occurs or {@link InputStream} length is less than {@code size}
* @throws IllegalArgumentException if size is less than zero or size is greater than Integer.MAX_VALUE
* @see IOUtils#toByteArray(InputStream, int)
* @since 2.1
*/
public static byte[] toByteArray(final InputStream input, final long size) throws IOException {
if (size > Integer.MAX_VALUE) {
throw new IllegalArgumentException("Size cannot be greater than Integer max value: " + size);
}
return toByteArray(input, (int) size);
}
/**
* Gets the contents of an input as a {@code byte[]}.
*
* @param input the input to read.
* @param size the size of the input to read, where 0 < {@code size} <= length of input.
* @return byte [] of length {@code size}.
* @throws IOException if an I/O error occurs or input length is smaller than parameter {@code size}.
* @throws IllegalArgumentException if {@code size} is less than zero.
*/
static byte[] toByteArray(final IOTriFunction<byte[], Integer, Integer, Integer> input, final int size) throws IOException {
if (size < 0) {
throw new IllegalArgumentException("Size must be equal or greater than zero: " + size);
}
if (size == 0) {
return EMPTY_BYTE_ARRAY;
}
final byte[] data = byteArray(size);
int offset = 0;
int read;
while (offset < size && (read = input.apply(data, offset, size - offset)) != EOF) {
offset += read;
}
if (offset != size) {
throw new IOException("Unexpected read size, current: " + offset + ", expected: " + size);
}
return data;
}
/**
* Gets the contents of a {@link Reader} as a {@code byte[]}
* using the default character encoding of the platform.
* <p>
* This method buffers the input internally, so there is no need to use a
* {@link BufferedReader}.
* </p>
*
* @param reader the {@link Reader} to read
* @return the requested byte array
* @throws NullPointerException if the input is null
* @throws IOException if an I/O error occurs
* @deprecated Use {@link #toByteArray(Reader, Charset)} instead
*/
@Deprecated
public static byte[] toByteArray(final Reader reader) throws IOException {
return toByteArray(reader, Charset.defaultCharset());
}
/**
* Gets the contents of a {@link Reader} as a {@code byte[]}
* using the specified character encoding.
* <p>
* This method buffers the input internally, so there is no need to use a
* {@link BufferedReader}.
* </p>
*
* @param reader the {@link Reader} to read
* @param charset the charset to use, null means platform default
* @return the requested byte array
* @throws NullPointerException if the input is null
* @throws IOException if an I/O error occurs
* @since 2.3
*/
public static byte[] toByteArray(final Reader reader, final Charset charset) throws IOException {
try (ByteArrayOutputStream output = new ByteArrayOutputStream()) {
copy(reader, output, charset);
return output.toByteArray();
}
}
/**
* Gets the contents of a {@link Reader} as a {@code byte[]}
* using the specified character encoding.
* <p>
* Character encoding names can be found at
* <a href="http://www.iana.org/assignments/character-sets">IANA</a>.
* </p>
* <p>
* This method buffers the input internally, so there is no need to use a
* {@link BufferedReader}.
* </p>
*
* @param reader the {@link Reader} to read
* @param charsetName the name of the requested charset, null means platform default
* @return the requested byte array
* @throws NullPointerException if the input is null
* @throws IOException if an I/O error occurs
* @throws java.nio.charset.UnsupportedCharsetException if the encoding is not supported
* @since 1.1
*/
public static byte[] toByteArray(final Reader reader, final String charsetName) throws IOException {
return toByteArray(reader, Charsets.toCharset(charsetName));
}
/**
* Gets the contents of a {@link String} as a {@code byte[]}
* using the default character encoding of the platform.
* <p>
* This is the same as {@link String#getBytes()}.
* </p>
*
* @param input the {@link String} to convert
* @return the requested byte array
* @throws NullPointerException if the input is null
* @deprecated Use {@link String#getBytes()} instead
*/
@Deprecated
public static byte[] toByteArray(final String input) {
// make explicit the use of the default charset
return input.getBytes(Charset.defaultCharset());
}
/**
* Gets the contents of a {@link URI} as a {@code byte[]}.
*
* @param uri the {@link URI} to read
* @return the requested byte array
* @throws NullPointerException if the uri is null
* @throws IOException if an I/O exception occurs
* @since 2.4
*/
public static byte[] toByteArray(final URI uri) throws IOException {
return toByteArray(uri.toURL());
}
/**
* Gets the contents of a {@link URL} as a {@code byte[]}.
*
* @param url the {@link URL} to read
* @return the requested byte array
* @throws NullPointerException if the input is null
* @throws IOException if an I/O exception occurs
* @since 2.4
*/
public static byte[] toByteArray(final URL url) throws IOException {
try (CloseableURLConnection urlConnection = CloseableURLConnection.open(url)) {
return toByteArray(urlConnection);
}
}
/**
* Gets the contents of a {@link URLConnection} as a {@code byte[]}.
*
* @param urlConnection the {@link URLConnection} to read.
* @return the requested byte array.
* @throws NullPointerException if the urlConn is null.
* @throws IOException if an I/O exception occurs.
* @since 2.4
*/
public static byte[] toByteArray(final URLConnection urlConnection) throws IOException {
try (InputStream inputStream = urlConnection.getInputStream()) {
return toByteArray(inputStream);
}
}
/**
* Gets the contents of an {@link InputStream} as a character array
* using the default character encoding of the platform.
* <p>
* This method buffers the input internally, so there is no need to use a
* {@link BufferedInputStream}.
* </p>
*
* @param inputStream the {@link InputStream} to read
* @return the requested character array
* @throws NullPointerException if the input is null
* @throws IOException if an I/O error occurs
* @since 1.1
* @deprecated Use {@link #toCharArray(InputStream, Charset)} instead
*/
@Deprecated
public static char[] toCharArray(final InputStream inputStream) throws IOException {
return toCharArray(inputStream, Charset.defaultCharset());
}
/**
* Gets the contents of an {@link InputStream} as a character array
* using the specified character encoding.
* <p>
* This method buffers the input internally, so there is no need to use a
* {@link BufferedInputStream}.
* </p>
*
* @param inputStream the {@link InputStream} to read
* @param charset the charset to use, null means platform default
* @return the requested character array
* @throws NullPointerException if the input is null
* @throws IOException if an I/O error occurs
* @since 2.3
*/
public static char[] toCharArray(final InputStream inputStream, final Charset charset)
throws IOException {
final CharArrayWriter writer = new CharArrayWriter();
copy(inputStream, writer, charset);
return writer.toCharArray();
}
/**
* Gets the contents of an {@link InputStream} as a character array
* using the specified character encoding.
* <p>
* Character encoding names can be found at
* <a href="http://www.iana.org/assignments/character-sets">IANA</a>.
* </p>
* <p>
* This method buffers the input internally, so there is no need to use a
* {@link BufferedInputStream}.
* </p>
*
* @param inputStream the {@link InputStream} to read
* @param charsetName the name of the requested charset, null means platform default
* @return the requested character array
* @throws NullPointerException if the input is null
* @throws IOException if an I/O error occurs
* @throws java.nio.charset.UnsupportedCharsetException if the encoding is not supported
* @since 1.1
*/
public static char[] toCharArray(final InputStream inputStream, final String charsetName) throws IOException {
return toCharArray(inputStream, Charsets.toCharset(charsetName));
}
/**
* Gets the contents of a {@link Reader} as a character array.
* <p>
* This method buffers the input internally, so there is no need to use a
* {@link BufferedReader}.
* </p>
*
* @param reader the {@link Reader} to read
* @return the requested character array
* @throws NullPointerException if the input is null
* @throws IOException if an I/O error occurs
* @since 1.1
*/
public static char[] toCharArray(final Reader reader) throws IOException {
final CharArrayWriter sw = new CharArrayWriter();
copy(reader, sw);
return sw.toCharArray();
}
/**
* Converts the specified CharSequence to an input stream, encoded as bytes
* using the default character encoding of the platform.
*
* @param input the CharSequence to convert
* @return an input stream
* @since 2.0
* @deprecated Use {@link #toInputStream(CharSequence, Charset)} instead
*/
@Deprecated
public static InputStream toInputStream(final CharSequence input) {
return toInputStream(input, Charset.defaultCharset());
}
/**
* Converts the specified CharSequence to an input stream, encoded as bytes
* using the specified character encoding.
*
* @param input the CharSequence to convert
* @param charset the charset to use, null means platform default
* @return an input stream
* @since 2.3
*/
public static InputStream toInputStream(final CharSequence input, final Charset charset) {
return toInputStream(input.toString(), charset);
}
/**
* Converts the specified CharSequence to an input stream, encoded as bytes
* using the specified character encoding.
* <p>
* Character encoding names can be found at
* <a href="http://www.iana.org/assignments/character-sets">IANA</a>.
* </p>
*
* @param input the CharSequence to convert
* @param charsetName the name of the requested charset, null means platform default
* @return an input stream
* @throws java.nio.charset.UnsupportedCharsetException if the encoding is not supported
* @since 2.0
*/
public static InputStream toInputStream(final CharSequence input, final String charsetName) {
return toInputStream(input, Charsets.toCharset(charsetName));
}
/**
* Converts the specified string to an input stream, encoded as bytes
* using the default character encoding of the platform.
*
* @param input the string to convert
* @return an input stream
* @since 1.1
* @deprecated Use {@link #toInputStream(String, Charset)} instead
*/
@Deprecated
public static InputStream toInputStream(final String input) {
return toInputStream(input, Charset.defaultCharset());
}
/**
* Converts the specified string to an input stream, encoded as bytes
* using the specified character encoding.
*
* @param input the string to convert
* @param charset the charset to use, null means platform default
* @return an input stream
* @since 2.3
*/
public static InputStream toInputStream(final String input, final Charset charset) {
return new ByteArrayInputStream(input.getBytes(Charsets.toCharset(charset)));
}
/**
* Converts the specified string to an input stream, encoded as bytes
* using the specified character encoding.
* <p>
* Character encoding names can be found at
* <a href="http://www.iana.org/assignments/character-sets">IANA</a>.
* </p>
*
* @param input the string to convert
* @param charsetName the name of the requested charset, null means platform default
* @return an input stream
* @throws java.nio.charset.UnsupportedCharsetException if the encoding is not supported
* @since 1.1
*/
public static InputStream toInputStream(final String input, final String charsetName) {
return new ByteArrayInputStream(input.getBytes(Charsets.toCharset(charsetName)));
}
/**
* Gets the contents of a {@code byte[]} as a String
* using the default character encoding of the platform.
*
* @param input the byte array to read
* @return the requested String
* @throws NullPointerException if the input is null
* @deprecated Use {@link String#String(byte[])} instead
*/
@Deprecated
public static String toString(final byte[] input) {
// make explicit the use of the default charset
return new String(input, Charset.defaultCharset());
}
/**
* Gets the contents of a {@code byte[]} as a String
* using the specified character encoding.
* <p>
* Character encoding names can be found at
* <a href="http://www.iana.org/assignments/character-sets">IANA</a>.
* </p>
*
* @param input the byte array to read
* @param charsetName the name of the requested charset, null means platform default
* @return the requested String
* @throws NullPointerException if the input is null
*/
public static String toString(final byte[] input, final String charsetName) {
return new String(input, Charsets.toCharset(charsetName));
}
/**
* Gets the contents of an {@link InputStream} as a String
* using the default character encoding of the platform.
* <p>
* This method buffers the input internally, so there is no need to use a
* {@link BufferedInputStream}.
* </p>
*
* @param input the {@link InputStream} to read
* @return the requested String
* @throws NullPointerException if the input is null
* @throws IOException if an I/O error occurs
* @deprecated Use {@link #toString(InputStream, Charset)} instead
*/
@Deprecated
public static String toString(final InputStream input) throws IOException {
return toString(input, Charset.defaultCharset());
}
/**
* Gets the contents of an {@link InputStream} as a String
* using the specified character encoding.
* <p>
* This method buffers the input internally, so there is no need to use a
* {@link BufferedInputStream}.
* </p>
*
* @param input the {@link InputStream} to read
* @param charset the charset to use, null means platform default
* @return the requested String
* @throws NullPointerException if the input is null
* @throws IOException if an I/O error occurs
* @since 2.3
*/
public static String toString(final InputStream input, final Charset charset) throws IOException {
try (StringBuilderWriter sw = new StringBuilderWriter()) {
copy(input, sw, charset);
return sw.toString();
}
}
/**
* Gets the contents of an {@link InputStream} as a String
* using the specified character encoding.
* <p>
* Character encoding names can be found at
* <a href="http://www.iana.org/assignments/character-sets">IANA</a>.
* </p>
* <p>
* This method buffers the input internally, so there is no need to use a
* {@link BufferedInputStream}.
* </p>
*
* @param input the {@link InputStream} to read
* @param charsetName the name of the requested charset, null means platform default
* @return the requested String
* @throws NullPointerException if the input is null
* @throws IOException if an I/O error occurs
* @throws java.nio.charset.UnsupportedCharsetException if the encoding is not supported
*/
public static String toString(final InputStream input, final String charsetName)
throws IOException {
return toString(input, Charsets.toCharset(charsetName));
}
/**
* Gets the contents of an {@link InputStream} from a supplier as a String
* using the specified character encoding.
* <p>
* This method buffers the input internally, so there is no need to use a
* {@link BufferedInputStream}.
* </p>
*
* @param input supplies the {@link InputStream} to read
* @param charset the charset to use, null means platform default
* @return the requested String
* @throws NullPointerException if the input is null
* @throws IOException if an I/O error occurs
* @since 2.12.0
*/
public static String toString(final IOSupplier<InputStream> input, final Charset charset) throws IOException {
return toString(input, charset, () -> {
throw new NullPointerException("input");
});
}
/**
* Gets the contents of an {@link InputStream} from a supplier as a String
* using the specified character encoding.
* <p>
* This method buffers the input internally, so there is no need to use a
* {@link BufferedInputStream}.
* </p>
*
* @param input supplies the {@link InputStream} to read
* @param charset the charset to use, null means platform default
* @param defaultString the default return value if the supplier or its value is null.
* @return the requested String
* @throws NullPointerException if the input is null
* @throws IOException if an I/O error occurs
* @since 2.12.0
*/
public static String toString(final IOSupplier<InputStream> input, final Charset charset, final IOSupplier<String> defaultString) throws IOException {
if (input == null) {
return defaultString.get();
}
try (InputStream inputStream = input.get()) {
return inputStream != null ? toString(inputStream, charset) : defaultString.get();
}
}
/**
* Gets the contents of a {@link Reader} as a String.
* <p>
* This method buffers the input internally, so there is no need to use a
* {@link BufferedReader}.
* </p>
*
* @param reader the {@link Reader} to read
* @return the requested String
* @throws NullPointerException if the input is null
* @throws IOException if an I/O error occurs
*/
public static String toString(final Reader reader) throws IOException {
try (StringBuilderWriter sw = new StringBuilderWriter()) {
copy(reader, sw);
return sw.toString();
}
}
/**
* Gets the contents at the given URI.
*
* @param uri The URI source.
* @return The contents of the URL as a String.
* @throws IOException if an I/O exception occurs.
* @since 2.1
* @deprecated Use {@link #toString(URI, Charset)} instead
*/
@Deprecated
public static String toString(final URI uri) throws IOException {
return toString(uri, Charset.defaultCharset());
}
/**
* Gets the contents at the given URI.
*
* @param uri The URI source.
* @param encoding The encoding name for the URL contents.
* @return The contents of the URL as a String.
* @throws IOException if an I/O exception occurs.
* @since 2.3.
*/
public static String toString(final URI uri, final Charset encoding) throws IOException {
return toString(uri.toURL(), Charsets.toCharset(encoding));
}
/**
* Gets the contents at the given URI.
*
* @param uri The URI source.
* @param charsetName The encoding name for the URL contents.
* @return The contents of the URL as a String.
* @throws IOException if an I/O exception occurs.
* @throws java.nio.charset.UnsupportedCharsetException if the encoding is not supported
* @since 2.1
*/
public static String toString(final URI uri, final String charsetName) throws IOException {
return toString(uri, Charsets.toCharset(charsetName));
}
/**
* Gets the contents at the given URL.
*
* @param url The URL source.
* @return The contents of the URL as a String.
* @throws IOException if an I/O exception occurs.
* @since 2.1
* @deprecated Use {@link #toString(URL, Charset)} instead
*/
@Deprecated
public static String toString(final URL url) throws IOException {
return toString(url, Charset.defaultCharset());
}
/**
* Gets the contents at the given URL.
*
* @param url The URL source.
* @param encoding The encoding name for the URL contents.
* @return The contents of the URL as a String.
* @throws IOException if an I/O exception occurs.
* @since 2.3
*/
public static String toString(final URL url, final Charset encoding) throws IOException {
return toString(url::openStream, encoding);
}
/**
* Gets the contents at the given URL.
*
* @param url The URL source.
* @param charsetName The encoding name for the URL contents.
* @return The contents of the URL as a String.
* @throws IOException if an I/O exception occurs.
* @throws java.nio.charset.UnsupportedCharsetException if the encoding is not supported
* @since 2.1
*/
public static String toString(final URL url, final String charsetName) throws IOException {
return toString(url, Charsets.toCharset(charsetName));
}
/**
* Writes bytes from a {@code byte[]} to an {@link OutputStream}.
*
* @param data the byte array to write, do not modify during output,
* null ignored
* @param output the {@link OutputStream} to write to
* @throws NullPointerException if output is null
* @throws IOException if an I/O error occurs
* @since 1.1
*/
public static void write(final byte[] data, final OutputStream output)
throws IOException {
if (data != null) {
output.write(data);
}
}
/**
* Writes bytes from a {@code byte[]} to chars on a {@link Writer}
* using the default character encoding of the platform.
* <p>
* This method uses {@link String#String(byte[])}.
* </p>
*
* @param data the byte array to write, do not modify during output,
* null ignored
* @param writer the {@link Writer} to write to
* @throws NullPointerException if output is null
* @throws IOException if an I/O error occurs
* @since 1.1
* @deprecated Use {@link #write(byte[], Writer, Charset)} instead
*/
@Deprecated
public static void write(final byte[] data, final Writer writer) throws IOException {
write(data, writer, Charset.defaultCharset());
}
/**
* Writes bytes from a {@code byte[]} to chars on a {@link Writer}
* using the specified character encoding.
* <p>
* This method uses {@link String#String(byte[], String)}.
* </p>
*
* @param data the byte array to write, do not modify during output,
* null ignored
* @param writer the {@link Writer} to write to
* @param charset the charset to use, null means platform default
* @throws NullPointerException if output is null
* @throws IOException if an I/O error occurs
* @since 2.3
*/
public static void write(final byte[] data, final Writer writer, final Charset charset) throws IOException {
if (data != null) {
writer.write(new String(data, Charsets.toCharset(charset)));
}
}
/**
* Writes bytes from a {@code byte[]} to chars on a {@link Writer}
* using the specified character encoding.
* <p>
* Character encoding names can be found at
* <a href="http://www.iana.org/assignments/character-sets">IANA</a>.
* </p>
* <p>
* This method uses {@link String#String(byte[], String)}.
* </p>
*
* @param data the byte array to write, do not modify during output,
* null ignored
* @param writer the {@link Writer} to write to
* @param charsetName the name of the requested charset, null means platform default
* @throws NullPointerException if output is null
* @throws IOException if an I/O error occurs
* @throws java.nio.charset.UnsupportedCharsetException if the encoding is not supported
* @since 1.1
*/
public static void write(final byte[] data, final Writer writer, final String charsetName) throws IOException {
write(data, writer, Charsets.toCharset(charsetName));
}
/**
* Writes chars from a {@code char[]} to bytes on an
* {@link OutputStream}.
* <p>
* This method uses {@link String#String(char[])} and
* {@link String#getBytes()}.
* </p>
*
* @param data the char array to write, do not modify during output,
* null ignored
* @param output the {@link OutputStream} to write to
* @throws NullPointerException if output is null
* @throws IOException if an I/O error occurs
* @since 1.1
* @deprecated Use {@link #write(char[], OutputStream, Charset)} instead
*/
@Deprecated
public static void write(final char[] data, final OutputStream output)
throws IOException {
write(data, output, Charset.defaultCharset());
}
/**
* Writes chars from a {@code char[]} to bytes on an
* {@link OutputStream} using the specified character encoding.
* <p>
* This method uses {@link String#String(char[])} and
* {@link String#getBytes(String)}.
* </p>
*
* @param data the char array to write, do not modify during output,
* null ignored
* @param output the {@link OutputStream} to write to
* @param charset the charset to use, null means platform default
* @throws NullPointerException if output is null
* @throws IOException if an I/O error occurs
* @since 2.3
*/
public static void write(final char[] data, final OutputStream output, final Charset charset) throws IOException {
if (data != null) {
write(new String(data), output, charset);
}
}
/**
* Writes chars from a {@code char[]} to bytes on an
* {@link OutputStream} using the specified character encoding.
* <p>
* Character encoding names can be found at
* <a href="http://www.iana.org/assignments/character-sets">IANA</a>.
* </p>
* <p>
* This method uses {@link String#String(char[])} and
* {@link String#getBytes(String)}.
* </p>
*
* @param data the char array to write, do not modify during output,
* null ignored
* @param output the {@link OutputStream} to write to
* @param charsetName the name of the requested charset, null means platform default
* @throws NullPointerException if output is null
* @throws IOException if an I/O error occurs
* @throws java.nio.charset.UnsupportedCharsetException if the encoding is not supported
* @since 1.1
*/
public static void write(final char[] data, final OutputStream output, final String charsetName)
throws IOException {
write(data, output, Charsets.toCharset(charsetName));
}
/**
* Writes chars from a {@code char[]} to a {@link Writer}
*
* @param data the char array to write, do not modify during output,
* null ignored
* @param writer the {@link Writer} to write to
* @throws NullPointerException if output is null
* @throws IOException if an I/O error occurs
* @since 1.1
*/
public static void write(final char[] data, final Writer writer) throws IOException {
if (data != null) {
writer.write(data);
}
}
/**
* Writes chars from a {@link CharSequence} to bytes on an
* {@link OutputStream} using the default character encoding of the
* platform.
* <p>
* This method uses {@link String#getBytes()}.
* </p>
*
* @param data the {@link CharSequence} to write, null ignored
* @param output the {@link OutputStream} to write to
* @throws NullPointerException if output is null
* @throws IOException if an I/O error occurs
* @since 2.0
* @deprecated Use {@link #write(CharSequence, OutputStream, Charset)} instead
*/
@Deprecated
public static void write(final CharSequence data, final OutputStream output)
throws IOException {
write(data, output, Charset.defaultCharset());
}
/**
* Writes chars from a {@link CharSequence} to bytes on an
* {@link OutputStream} using the specified character encoding.
* <p>
* This method uses {@link String#getBytes(String)}.
* </p>
*
* @param data the {@link CharSequence} to write, null ignored
* @param output the {@link OutputStream} to write to
* @param charset the charset to use, null means platform default
* @throws NullPointerException if output is null
* @throws IOException if an I/O error occurs
* @since 2.3
*/
public static void write(final CharSequence data, final OutputStream output, final Charset charset)
throws IOException {
if (data != null) {
write(data.toString(), output, charset);
}
}
/**
* Writes chars from a {@link CharSequence} to bytes on an
* {@link OutputStream} using the specified character encoding.
* <p>
* Character encoding names can be found at
* <a href="http://www.iana.org/assignments/character-sets">IANA</a>.
* </p>
* <p>
* This method uses {@link String#getBytes(String)}.
* </p>
*
* @param data the {@link CharSequence} to write, null ignored
* @param output the {@link OutputStream} to write to
* @param charsetName the name of the requested charset, null means platform default
* @throws NullPointerException if output is null
* @throws IOException if an I/O error occurs
* @throws java.nio.charset.UnsupportedCharsetException if the encoding is not supported
* @since 2.0
*/
public static void write(final CharSequence data, final OutputStream output, final String charsetName)
throws IOException {
write(data, output, Charsets.toCharset(charsetName));
}
/**
* Writes chars from a {@link CharSequence} to a {@link Writer}.
*
* @param data the {@link CharSequence} to write, null ignored
* @param writer the {@link Writer} to write to
* @throws NullPointerException if output is null
* @throws IOException if an I/O error occurs
* @since 2.0
*/
public static void write(final CharSequence data, final Writer writer) throws IOException {
if (data != null) {
write(data.toString(), writer);
}
}
/**
* Writes chars from a {@link String} to bytes on an
* {@link OutputStream} using the default character encoding of the
* platform.
* <p>
* This method uses {@link String#getBytes()}.
* </p>
*
* @param data the {@link String} to write, null ignored
* @param output the {@link OutputStream} to write to
* @throws NullPointerException if output is null
* @throws IOException if an I/O error occurs
* @since 1.1
* @deprecated Use {@link #write(String, OutputStream, Charset)} instead
*/
@Deprecated
public static void write(final String data, final OutputStream output)
throws IOException {
write(data, output, Charset.defaultCharset());
}
/**
* Writes chars from a {@link String} to bytes on an
* {@link OutputStream} using the specified character encoding.
* <p>
* This method uses {@link String#getBytes(String)}.
* </p>
*
* @param data the {@link String} to write, null ignored
* @param output the {@link OutputStream} to write to
* @param charset the charset to use, null means platform default
* @throws NullPointerException if output is null
* @throws IOException if an I/O error occurs
* @since 2.3
*/
@SuppressWarnings("resource")
public static void write(final String data, final OutputStream output, final Charset charset) throws IOException {
if (data != null) {
// Use Charset#encode(String), since calling String#getBytes(Charset) might result in
// NegativeArraySizeException or OutOfMemoryError.
// The underlying OutputStream should not be closed, so the channel is not closed.
Channels.newChannel(output).write(Charsets.toCharset(charset).encode(data));
}
}
/**
* Writes chars from a {@link String} to bytes on an
* {@link OutputStream} using the specified character encoding.
* <p>
* Character encoding names can be found at
* <a href="http://www.iana.org/assignments/character-sets">IANA</a>.
* </p>
* <p>
* This method uses {@link String#getBytes(String)}.
* </p>
*
* @param data the {@link String} to write, null ignored
* @param output the {@link OutputStream} to write to
* @param charsetName the name of the requested charset, null means platform default
* @throws NullPointerException if output is null
* @throws IOException if an I/O error occurs
* @throws java.nio.charset.UnsupportedCharsetException if the encoding is not supported
* @since 1.1
*/
public static void write(final String data, final OutputStream output, final String charsetName)
throws IOException {
write(data, output, Charsets.toCharset(charsetName));
}
/**
* Writes chars from a {@link String} to a {@link Writer}.
*
* @param data the {@link String} to write, null ignored
* @param writer the {@link Writer} to write to
* @throws NullPointerException if output is null
* @throws IOException if an I/O error occurs
* @since 1.1
*/
public static void write(final String data, final Writer writer) throws IOException {
if (data != null) {
writer.write(data);
}
}
/**
* Writes chars from a {@link StringBuffer} to bytes on an
* {@link OutputStream} using the default character encoding of the
* platform.
* <p>
* This method uses {@link String#getBytes()}.
* </p>
*
* @param data the {@link StringBuffer} to write, null ignored
* @param output the {@link OutputStream} to write to
* @throws NullPointerException if output is null
* @throws IOException if an I/O error occurs
* @since 1.1
* @deprecated Use {@link #write(CharSequence, OutputStream)}
*/
@Deprecated
public static void write(final StringBuffer data, final OutputStream output) //NOSONAR
throws IOException {
write(data, output, (String) null);
}
/**
* Writes chars from a {@link StringBuffer} to bytes on an
* {@link OutputStream} using the specified character encoding.
* <p>
* Character encoding names can be found at
* <a href="http://www.iana.org/assignments/character-sets">IANA</a>.
* </p>
* <p>
* This method uses {@link String#getBytes(String)}.
* </p>
*
* @param data the {@link StringBuffer} to write, null ignored
* @param output the {@link OutputStream} to write to
* @param charsetName the name of the requested charset, null means platform default
* @throws NullPointerException if output is null
* @throws IOException if an I/O error occurs
* @throws java.nio.charset.UnsupportedCharsetException if the encoding is not supported
* @since 1.1
* @deprecated Use {@link #write(CharSequence, OutputStream, String)}.
*/
@Deprecated
public static void write(final StringBuffer data, final OutputStream output, final String charsetName) //NOSONAR
throws IOException {
if (data != null) {
write(data.toString(), output, Charsets.toCharset(charsetName));
}
}
/**
* Writes chars from a {@link StringBuffer} to a {@link Writer}.
*
* @param data the {@link StringBuffer} to write, null ignored
* @param writer the {@link Writer} to write to
* @throws NullPointerException if output is null
* @throws IOException if an I/O error occurs
* @since 1.1
* @deprecated Use {@link #write(CharSequence, Writer)}
*/
@Deprecated
public static void write(final StringBuffer data, final Writer writer) //NOSONAR
throws IOException {
if (data != null) {
writer.write(data.toString());
}
}
/**
* Writes bytes from a {@code byte[]} to an {@link OutputStream} using chunked writes.
* This is intended for writing very large byte arrays which might otherwise cause excessive
* memory usage if the native code has to allocate a copy.
*
* @param data the byte array to write, do not modify during output,
* null ignored
* @param output the {@link OutputStream} to write to
* @throws NullPointerException if output is null
* @throws IOException if an I/O error occurs
* @since 2.5
*/
public static void writeChunked(final byte[] data, final OutputStream output)
throws IOException {
if (data != null) {
int bytes = data.length;
int offset = 0;
while (bytes > 0) {
final int chunk = Math.min(bytes, DEFAULT_BUFFER_SIZE);
output.write(data, offset, chunk);
bytes -= chunk;
offset += chunk;
}
}
}
/**
* Writes chars from a {@code char[]} to a {@link Writer} using chunked writes.
* This is intended for writing very large byte arrays which might otherwise cause excessive
* memory usage if the native code has to allocate a copy.
*
* @param data the char array to write, do not modify during output,
* null ignored
* @param writer the {@link Writer} to write to
* @throws NullPointerException if output is null
* @throws IOException if an I/O error occurs
* @since 2.5
*/
public static void writeChunked(final char[] data, final Writer writer) throws IOException {
if (data != null) {
int bytes = data.length;
int offset = 0;
while (bytes > 0) {
final int chunk = Math.min(bytes, DEFAULT_BUFFER_SIZE);
writer.write(data, offset, chunk);
bytes -= chunk;
offset += chunk;
}
}
}
/**
* Writes the {@link #toString()} value of each item in a collection to
* an {@link OutputStream} line by line, using the default character
* encoding of the platform and the specified line ending.
*
* @param lines the lines to write, null entries produce blank lines
* @param lineEnding the line separator to use, null is system default
* @param output the {@link OutputStream} to write to, not null, not closed
* @throws NullPointerException if the output is null
* @throws IOException if an I/O error occurs
* @since 1.1
* @deprecated Use {@link #writeLines(Collection, String, OutputStream, Charset)} instead
*/
@Deprecated
public static void writeLines(final Collection<?> lines, final String lineEnding,
final OutputStream output) throws IOException {
writeLines(lines, lineEnding, output, Charset.defaultCharset());
}
/**
* Writes the {@link #toString()} value of each item in a collection to
* an {@link OutputStream} line by line, using the specified character
* encoding and the specified line ending.
* <p>
* UTF-16 is written big-endian with no byte order mark.
* For little-endian, use UTF-16LE. For a BOM, write it to the stream
* before calling this method.
* </p>
*
* @param lines the lines to write, null entries produce blank lines
* @param lineEnding the line separator to use, null is system default
* @param output the {@link OutputStream} to write to, not null, not closed
* @param charset the charset to use, null means platform default
* @throws NullPointerException if output is null
* @throws IOException if an I/O error occurs
* @since 2.3
*/
public static void writeLines(final Collection<?> lines, String lineEnding, final OutputStream output,
Charset charset) throws IOException {
if (lines == null) {
return;
}
if (lineEnding == null) {
lineEnding = System.lineSeparator();
}
if (StandardCharsets.UTF_16.equals(charset)) {
// don't write a BOM
charset = StandardCharsets.UTF_16BE;
}
final byte[] eolBytes = lineEnding.getBytes(charset);
for (final Object line : lines) {
if (line != null) {
write(line.toString(), output, charset);
}
output.write(eolBytes);
}
}
/**
* Writes the {@link #toString()} value of each item in a collection to
* an {@link OutputStream} line by line, using the specified character
* encoding and the specified line ending.
* <p>
* Character encoding names can be found at
* <a href="http://www.iana.org/assignments/character-sets">IANA</a>.
* </p>
*
* @param lines the lines to write, null entries produce blank lines
* @param lineEnding the line separator to use, null is system default
* @param output the {@link OutputStream} to write to, not null, not closed
* @param charsetName the name of the requested charset, null means platform default
* @throws NullPointerException if the output is null
* @throws IOException if an I/O error occurs
* @throws java.nio.charset.UnsupportedCharsetException if the encoding is not supported
* @since 1.1
*/
public static void writeLines(final Collection<?> lines, final String lineEnding,
final OutputStream output, final String charsetName) throws IOException {
writeLines(lines, lineEnding, output, Charsets.toCharset(charsetName));
}
/**
* Writes the {@link #toString()} value of each item in a collection to
* a {@link Writer} line by line, using the specified line ending.
*
* @param lines the lines to write, null entries produce blank lines
* @param lineEnding the line separator to use, null is system default
* @param writer the {@link Writer} to write to, not null, not closed
* @throws NullPointerException if the input is null
* @throws IOException if an I/O error occurs
* @since 1.1
*/
public static void writeLines(final Collection<?> lines, String lineEnding,
final Writer writer) throws IOException {
if (lines == null) {
return;
}
if (lineEnding == null) {
lineEnding = System.lineSeparator();
}
for (final Object line : lines) {
if (line != null) {
writer.write(line.toString());
}
writer.write(lineEnding);
}
}
/**
* Returns the given Appendable if it is already a {@link Writer}, otherwise creates a Writer wrapper around the
* given Appendable.
*
* @param appendable the Appendable to wrap or return (not null)
* @return the given Appendable or a Writer wrapper around the given Appendable
* @throws NullPointerException if the input parameter is null
* @since 2.7
*/
public static Writer writer(final Appendable appendable) {
Objects.requireNonNull(appendable, "appendable");
if (appendable instanceof Writer) {
return (Writer) appendable;
}
if (appendable instanceof StringBuilder) {
return new StringBuilderWriter((StringBuilder) appendable);
}
return new AppendableWriter<>(appendable);
}
/**
* Instances should NOT be constructed in standard programming.
*
* @deprecated TODO Make private in 3.0.
*/
@Deprecated
public IOUtils() { //NOSONAR
// empty
}
}