Package org.apache.commons.compress.archivers.tar

Class TarArchiveInputStream

java.lang.Object
java.io.InputStream
java.io.FilterInputStream
org.apache.commons.compress.archivers.ArchiveInputStream<TarArchiveEntry>
org.apache.commons.compress.archivers.tar.TarArchiveInputStream
All Implemented Interfaces:
Closeable, AutoCloseable
public class TarArchiveInputStream extends ArchiveInputStream<TarArchiveEntry>
The TarInputStream reads a UNIX tar archive as an InputStream. methods are provided to position at each successive entry in the archive, and the read each entry as a normal input stream using read().
This class is not thread-safe

  • Constructor Details

    • TarArchiveInputStream

      public TarArchiveInputStream(InputStream inputStream)
      Constructs a new instance.
      Parameters:
      inputStream - the input stream to use

    • TarArchiveInputStream

      public TarArchiveInputStream(InputStream inputStream, boolean lenient)
      Constructs a new instance.
      Parameters:
      inputStream - the input stream to use
      lenient - when set to true illegal values for group/userid, mode, device numbers and timestamp will be ignored and the fields set to TarArchiveEntry.UNKNOWN. When set to false such illegal fields cause an exception instead.
      Since:
      1.19

    • TarArchiveInputStream

      public TarArchiveInputStream(InputStream inputStream, int blockSize)
      Constructs a new instance.
      Parameters:
      inputStream - the input stream to use
      blockSize - the block size to use

    • TarArchiveInputStream

      public TarArchiveInputStream(InputStream inputStream, int blockSize, int recordSize)
      Constructs a new instance.
      Parameters:
      inputStream - the input stream to use
      blockSize - the block size to use
      recordSize - the record size to use

    • TarArchiveInputStream

      public TarArchiveInputStream(InputStream inputStream, int blockSize, int recordSize, String encoding)
      Constructs a new instance.
      Parameters:
      inputStream - the input stream to use
      blockSize - the block size to use
      recordSize - the record size to use
      encoding - name of the encoding to use for file names
      Since:
      1.4

    • TarArchiveInputStream

      public TarArchiveInputStream(InputStream inputStream, int blockSize, int recordSize, String encoding, boolean lenient)
      Constructs a new instance.
      Parameters:
      inputStream - the input stream to use
      blockSize - the block size to use
      recordSize - the record size to use
      encoding - name of the encoding to use for file names
      lenient - when set to true illegal values for group/userid, mode, device numbers and timestamp will be ignored and the fields set to TarArchiveEntry.UNKNOWN. When set to false such illegal fields cause an exception instead.
      Since:
      1.19

    • TarArchiveInputStream

      public TarArchiveInputStream(InputStream inputStream, int blockSize, String encoding)
      Constructs a new instance.
      Parameters:
      inputStream - the input stream to use
      blockSize - the block size to use
      encoding - name of the encoding to use for file names
      Since:
      1.4

    • TarArchiveInputStream

      public TarArchiveInputStream(InputStream inputStream, String encoding)
      Constructs a new instance.
      Parameters:
      inputStream - the input stream to use
      encoding - name of the encoding to use for file names
      Since:
      1.4

  • Method Details

    • matches

      public static boolean matches(byte[] signature, int length)
      Checks if the signature matches what is expected for a tar file.
      Parameters:
      signature - the bytes to check
      length - the number of bytes to check
      Returns:
      true, if this stream is a tar archive stream, false otherwise

    • available

      public int available() throws IOException
      Gets the available data that can be read from the current entry in the archive. This does not indicate how much data is left in the entire archive, only in the current entry. This value is determined from the entry's size header field and the amount of data already read from the current entry. Integer.MAX_VALUE is returned in case more than Integer.MAX_VALUE bytes are left in the current entry in the archive.
      Overrides:
      available in class FilterInputStream
      Returns:
      The number of available bytes for the current entry.
      Throws:
      IOException - for signature

    • canReadEntryData

      public boolean canReadEntryData(ArchiveEntry archiveEntry)
      Whether this class is able to read the given entry.
      Overrides:
      canReadEntryData in class ArchiveInputStream<TarArchiveEntry>
      Parameters:
      archiveEntry - the entry to test
      Returns:
      The implementation will return true if the ArchiveEntry is an instance of TarArchiveEntry

    • close

      public void close() throws IOException
      Closes this stream. Calls the TarBuffer's close() method.
      Specified by:
      close in interface AutoCloseable
      Specified by:
      close in interface Closeable
      Overrides:
      close in class FilterInputStream
      Throws:
      IOException - on error

    • getCurrentEntry

      public TarArchiveEntry getCurrentEntry()
      Gets the current TAR Archive Entry that this input stream is processing
      Returns:
      The current Archive Entry

    • getLongNameData

      protected byte[] getLongNameData() throws IOException
      Gets the next entry in this tar archive as long name data.
      Returns:
      The next entry in the archive as long name data, or null.
      Throws:
      IOException - on error

    • getNextEntry

      public TarArchiveEntry getNextEntry() throws IOException
      Gets the next TarArchiveEntry in this stream.
      Specified by:
      getNextEntry in class ArchiveInputStream<TarArchiveEntry>
      Returns:
      the next entry, or null if there are no more entries
      Throws:
      IOException - if the next entry could not be read

    • getNextTarEntry

      @Deprecated public TarArchiveEntry getNextTarEntry() throws IOException
      Deprecated.
      Use getNextEntry().
      Gets the next entry in this tar archive. This will skip over any remaining data in the current entry, if there is one, and place the input stream at the header of the next entry, and read the header and instantiate a new TarEntry from the header bytes and return that entry. If there are no more entries in the archive, null will be returned to indicate that the end of the archive has been reached.
      Returns:
      The next TarEntry in the archive, or null.
      Throws:
      IOException - on error

    • getRecordSize

      public int getRecordSize()
      Gets the record size being used by this stream's buffer.
      Returns:
      The TarBuffer record size.

    • isAtEOF

      protected final boolean isAtEOF()

    • isEOFRecord

      protected boolean isEOFRecord(byte[] record)
      Tests if an archive record indicate End of Archive. End of archive is indicated by a record that consists entirely of null bytes.
      Parameters:
      record - The record data to check.
      Returns:
      true if the record data is an End of Archive

    • mark

      public void mark(int markLimit)
      Since we do not support marking just yet, we do nothing.
      Overrides:
      mark in class ArchiveInputStream<TarArchiveEntry>
      Parameters:
      markLimit - The limit to mark.

    • markSupported

      public boolean markSupported()
      Since we do not support marking just yet, we return false.
      Overrides:
      markSupported in class ArchiveInputStream<TarArchiveEntry>
      Returns:
      false.

    • read

      public int read(byte[] buf, int offset, int numToRead) throws IOException
      Reads bytes from the current tar archive entry.

      This method is aware of the boundaries of the current entry in the archive and will deal with them as if they were this stream's start and EOF.

      Overrides:
      read in class FilterInputStream
      Parameters:
      buf - The buffer into which to place bytes read.
      offset - The offset at which to place bytes read.
      numToRead - The number of bytes to read.
      Returns:
      The number of bytes read, or -1 at EOF.
      Throws:
      IOException - on error

    • readRecord

      protected byte[] readRecord() throws IOException
      Read a record from the input stream and return the data.
      Returns:
      The record data or null if EOF has been hit.
      Throws:
      IOException - on error

    • reset

      public void reset()
      Since we do not support marking just yet, we do nothing.
      Overrides:
      reset in class ArchiveInputStream<TarArchiveEntry>

    • setAtEOF

      protected final void setAtEOF(boolean atEof)

    • setCurrentEntry

      protected final void setCurrentEntry(TarArchiveEntry currEntry)

    • skip

      public long skip(long n) throws IOException
      Skips over and discards n bytes of data from this input stream. The skip method may, for a variety of reasons, end up skipping over some smaller number of bytes, possibly 0. This may result from any of a number of conditions; reaching end of file or end of entry before n bytes have been skipped; are only two possibilities. The actual number of bytes skipped is returned. If n is negative, no bytes are skipped.
      Overrides:
      skip in class FilterInputStream
      Parameters:
      n - the number of bytes to be skipped.
      Returns:
      the actual number of bytes skipped.
      Throws:
      IOException - if a truncated tar archive is detected or some other I/O error occurs