# BZip2CompressorInputStream (Apache Commons Compress 1.13 API)

org.apache.commons.compress.compressors.bzip2

## Class BZip2CompressorInputStream

- java.lang.Object
- - java.io.InputStream
  - - org.apache.commons.compress.compressors.CompressorInputStream
    - - org.apache.commons.compress.compressors.bzip2.BZip2CompressorInputStream

- All Implemented Interfaces:
    Closeable, AutoCloseable

      public class BZip2CompressorInputStream
      extends CompressorInputStream

  An input stream that decompresses from the BZip2 format to be read as any other stream.
  This class is not thread-safe

- - ### Field Summary

    Fields
    Modifier and Type | Field and Description
    --- | ---
    `static int` | `BASEBLOCKSIZE`
    `static int` | `G_SIZE`
    `static int` | `MAX_ALPHA_SIZE`
    `static int` | `MAX_CODE_LEN`
    `static int` | `MAX_SELECTORS`
    `static int` | `N_GROUPS`
    `static int` | `N_ITERS`
    `static int` | `NUM_OVERSHOOT_BYTES`
    `static int` | `RUNA`
    `static int` | `RUNB`

  - ### Constructor Summary

    Constructors
    Constructor and Description
    `BZip2CompressorInputStream(InputStream in)` Constructs a new BZip2CompressorInputStream which decompresses bytes read from the specified stream.
    `BZip2CompressorInputStream(InputStream in, boolean decompressConcatenated)` Constructs a new BZip2CompressorInputStream which decompresses bytes read from the specified stream.

  - ### Method Summary

    Methods
    Modifier and Type | Method and Description
    --- | ---
    `void` | `close()`
    `static boolean` | `matches(byte[] signature, int length)` Checks if the signature matches what is expected for a bzip2 file.
    `int` | `read()`
    `int` | `read(byte[] dest, int offs, int len)`

    - ### Methods inherited from class org.apache.commons.compress.compressors.CompressorInputStream

      `count, count, getBytesRead, getCount, pushedBackBytes`

    - ### Methods inherited from class java.io.InputStream

      `available, mark, markSupported, read, reset, skip`

    - ### Methods inherited from class java.lang.Object

      `clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

- - ### Field Detail

    - #### BASEBLOCKSIZE

          public static final int BASEBLOCKSIZE

      See Also:
        Constant Field Values

    - #### MAX_ALPHA_SIZE

          public static final int MAX_ALPHA_SIZE

      See Also:
        Constant Field Values

    - #### MAX_CODE_LEN

          public static final int MAX_CODE_LEN

      See Also:
        Constant Field Values

    - #### RUNA

          public static final int RUNA

      See Also:
        Constant Field Values

    - #### RUNB

          public static final int RUNB

      See Also:
        Constant Field Values

    - #### N_GROUPS

          public static final int N_GROUPS

      See Also:
        Constant Field Values

    - #### G_SIZE

          public static final int G_SIZE

      See Also:
        Constant Field Values

    - #### N_ITERS

          public static final int N_ITERS

      See Also:
        Constant Field Values

    - #### MAX_SELECTORS

          public static final int MAX_SELECTORS

      See Also:
        Constant Field Values

    - #### NUM_OVERSHOOT_BYTES

          public static final int NUM_OVERSHOOT_BYTES

      See Also:
        Constant Field Values

  - ### Constructor Detail

    - #### BZip2CompressorInputStream

          public BZip2CompressorInputStream(InputStream in)
                                     throws IOException

      Constructs a new BZip2CompressorInputStream which decompresses bytes read from the specified stream. This doesn't suppprt decompressing concatenated .bz2 files.
      Parameters:
        `in` - the InputStream from which this object should be created
      Throws:
        `IOException` - if the stream content is malformed or an I/O error occurs.
        `NullPointerException` - if `in == null`

    - #### BZip2CompressorInputStream

          public BZip2CompressorInputStream(InputStream in,
                                    boolean decompressConcatenated)
                                     throws IOException

      Constructs a new BZip2CompressorInputStream which decompresses bytes read from the specified stream.
      Parameters:
        `in` - the InputStream from which this object should be created
        `decompressConcatenated` - if true, decompress until the end of the input; if false, stop after the first .bz2 stream and leave the input position to point to the next byte after the .bz2 stream
      Throws:
        `IOException` - if `in == null`, the stream content is malformed, or an I/O error occurs.

  - ### Method Detail

    - #### read

          public int read()
                   throws IOException

      Specified by:
        `read` in class `InputStream`
      Throws:
        `IOException`

    - #### read

          public int read(byte[] dest,
                 int offs,
                 int len)
                   throws IOException

      Overrides:
        `read` in class `InputStream`
      Throws:
        `IOException`

    - #### close

          public void close()
                     throws IOException

      Specified by:
        `close` in interface `Closeable`
      Specified by:
        `close` in interface `AutoCloseable`
      Overrides:
        `close` in class `InputStream`
      Throws:
        `IOException`

    - #### matches

          public static boolean matches(byte[] signature,
                        int length)

      Checks if the signature matches what is expected for a bzip2 file.
      Parameters:
        `signature` - the bytes to check
        `length` - the number of bytes to check
      Returns:
        true, if this stream is a bzip2 compressed stream, false otherwise
      Since:
        1.1

Copyright © 2016 The Apache Software Foundation. All rights reserved.