ZipLong.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.compress.archivers.zip;
import static org.apache.commons.compress.archivers.zip.ZipConstants.WORD;
import java.io.Serializable;
import org.apache.commons.compress.utils.ByteUtils;
/**
* Utility class that represents a four byte integer with conversion rules for the little-endian byte order of ZIP files.
*
* @Immutable
*/
public final class ZipLong implements Cloneable, Serializable {
private static final long serialVersionUID = 1L;
/** Central File Header Signature */
public static final ZipLong CFH_SIG = new ZipLong(0X02014B50L);
/** Local File Header Signature */
public static final ZipLong LFH_SIG = new ZipLong(0X04034B50L);
/**
* Data Descriptor signature.
*
* <p>
* Actually, PKWARE uses this as marker for split/spanned archives and other archivers have started to use it as Data Descriptor signature (as well).
* </p>
*
* @since 1.1
*/
public static final ZipLong DD_SIG = new ZipLong(0X08074B50L);
/**
* Value stored in size and similar fields if ZIP64 extensions are used.
*
* @since 1.3
*/
static final ZipLong ZIP64_MAGIC = new ZipLong(ZipConstants.ZIP64_MAGIC);
/**
* Marks ZIP archives that were supposed to be split or spanned but only needed a single segment in then end (so are actually neither split nor spanned).
*
* <p>
* This is the "PK00" prefix found in some archives.
* </p>
*
* @since 1.5
*/
public static final ZipLong SINGLE_SEGMENT_SPLIT_MARKER = new ZipLong(0X30304B50L);
/**
* Archive extra data record signature.
*
* @since 1.5
*/
public static final ZipLong AED_SIG = new ZipLong(0X08064B50L);
/**
* Gets value as four bytes in big-endian byte order.
*
* @param value the value to convert
* @return value as four bytes in big-endian byte order
*/
public static byte[] getBytes(final long value) {
final byte[] result = new byte[WORD];
putLong(value, result, 0);
return result;
}
/**
* Helper method to get the value as a Java long from a four-byte array
*
* @param bytes the array of bytes
* @return the corresponding Java long value
*/
public static long getValue(final byte[] bytes) {
return getValue(bytes, 0);
}
/**
* Helper method to get the value as a Java long from four bytes starting at given array offset
*
* @param bytes the array of bytes
* @param offset the offset to start
* @return the corresponding Java long value
*/
public static long getValue(final byte[] bytes, final int offset) {
return ByteUtils.fromLittleEndian(bytes, offset, 4);
}
/**
* put the value as four bytes in big-endian byte order.
*
* @param value the Java long to convert to bytes
* @param buf the output buffer
* @param offset The offset within the output buffer of the first byte to be written. must be non-negative and no larger than {@code buf.length-4}
*/
public static void putLong(final long value, final byte[] buf, final int offset) {
ByteUtils.toLittleEndian(buf, value, offset, 4);
}
private final long value;
/**
* Constructs a new instance from bytes.
*
* @param bytes the bytes to store as a ZipLong
*/
public ZipLong(final byte[] bytes) {
this(bytes, 0);
}
/**
* Creates instance from the four bytes starting at offset.
*
* @param bytes the bytes to store as a ZipLong
* @param offset the offset to start
*/
public ZipLong(final byte[] bytes, final int offset) {
value = getValue(bytes, offset);
}
/**
* create instance from a Java int.
*
* @param value the int to store as a ZipLong
* @since 1.15
*/
public ZipLong(final int value) {
this.value = value;
}
/**
* Creates instance from a number.
*
* @param value the long to store as a ZipLong
*/
public ZipLong(final long value) {
this.value = value;
}
@Override
public Object clone() {
try {
return super.clone();
} catch (final CloneNotSupportedException cnfe) {
// impossible
throw new UnsupportedOperationException(cnfe); // NOSONAR
}
}
/**
* Override to make two instances with same value equal.
*
* @param o an object to compare
* @return true if the objects are equal
*/
@Override
public boolean equals(final Object o) {
if (!(o instanceof ZipLong)) {
return false;
}
return value == ((ZipLong) o).getValue();
}
/**
* Gets value as four bytes in big-endian byte order.
*
* @return value as four bytes in big-endian order
*/
public byte[] getBytes() {
return getBytes(value);
}
/**
* Gets value as a (signed) Java int
*
* @return value as int
* @since 1.15
*/
public int getIntValue() {
return (int) value;
}
/**
* Gets value as Java long.
*
* @return value as a long
*/
public long getValue() {
return value;
}
/**
* Override to make two instances with same value equal.
*
* @return the value stored in the ZipLong
*/
@Override
public int hashCode() {
return (int) value;
}
public void putLong(final byte[] buf, final int offset) {
putLong(value, buf, offset);
}
@Override
public String toString() {
return "ZipLong value: " + value;
}
}