All Implemented Interfaces:
Closeable, AutoCloseable
Direct Known Subclasses:
GZIPInputStream, ZipInputStream

This class implements a stream filter for uncompressing data in the "deflate" compression format. It is also used as the basis for other decompression filters, such as GZIPInputStream.

Since:
1.1
See Also:

  • Field Summary

    Fields

    protected byte[]

    Input buffer for decompression.

    Decompressor for this stream.

    protected int

    The total number of bytes read into the input buffer.

  • Constructor Summary

    Constructors

    Creates a new input stream with a default decompressor and buffer size.

    Creates a new input stream with the specified decompressor and a default buffer size.

    Creates a new input stream with the specified decompressor and buffer size.

  • Method Summary

    int

    available()

    Returns 0 after EOF has been reached, otherwise always return 1.

    void

    close()

    Closes this input stream and releases any system resources associated with the stream.

    protected void

    fill()

    Fills input buffer with more data to decompress.

    void

    mark(int readlimit)

    Marks the current position in this input stream.

    boolean

    Tests if this input stream supports the mark and reset methods.

    int

    read()

    Reads a byte of uncompressed data.

    int

    read(byte[] b, int off, int len)

    Reads uncompressed data into an array of bytes, returning the number of inflated bytes.

    void

    reset()

    Repositions this stream to the position at the time the mark method was last called on this input stream.

    long

    skip(long n)

    Skips specified number of bytes of uncompressed data.

    Methods declared in class java.lang.Object

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

  • Field Details

    • inf

      Decompressor for this stream.

    • buf

      protected byte[] buf

      Input buffer for decompression.

    • len

      protected int len

      The total number of bytes read into the input buffer.

  • Constructor Details

    • InflaterInputStream

      Creates a new input stream with the specified decompressor and buffer size.

      Parameters:
      in - the input stream
      inf - the decompressor ("inflater")
      size - the input buffer size
      Throws:
      IllegalArgumentException - if size <= 0

    • InflaterInputStream

      Creates a new input stream with the specified decompressor and a default buffer size.

      Parameters:
      in - the input stream
      inf - the decompressor ("inflater")

    • InflaterInputStream

      Creates a new input stream with a default decompressor and buffer size.

      Parameters:
      in - the input stream

  • Method Details

    • read

      Reads a byte of uncompressed data. This method will block until enough input is available for decompression.

      Overrides:
      read in class FilterInputStream
      Returns:
      the byte read, or -1 if end of compressed input is reached
      Throws:
      IOException - if an I/O error has occurred
      See Also:

    • read

      public int read(byte[] b, int off, int len) throws IOException

      Reads uncompressed data into an array of bytes, returning the number of inflated bytes. If len is not zero, the method will block until some input can be decompressed; otherwise, no bytes are read and 0 is returned.

      If this method returns a nonzero integer n then buf[off] through buf[off+n-1] contain the uncompressed data. The content of elements buf[off+n] through buf[off+len-1] is undefined, contrary to the specification of the InputStream superclass, so an implementation is free to modify these elements during the inflate operation. If this method returns -1 or throws an exception then the content of buf[off] through buf[off+len -1] is undefined.

      Overrides:
      read in class FilterInputStream
      Parameters:
      b - the buffer into which the data is read
      off - the start offset in the destination array b
      len - the maximum number of bytes read
      Returns:
      the actual number of bytes inflated, or -1 if the end of the compressed input is reached or a preset dictionary is needed
      Throws:
      NullPointerException - If b is null.
      IndexOutOfBoundsException - If off is negative, len is negative, or len is greater than b.length - off
      ZipException - if a ZIP format error has occurred
      IOException - if an I/O error has occurred
      See Also:

    • available

      Returns 0 after EOF has been reached, otherwise always return 1.

      Programs should not count on this method to return the actual number of bytes that could be read without blocking.

      Overrides:
      available in class FilterInputStream
      Returns:
      1 before EOF and 0 after EOF.
      Throws:
      IOException - if an I/O error occurs.

    • skip

      Skips specified number of bytes of uncompressed data.

      Overrides:
      skip in class FilterInputStream
      Parameters:
      n - the number of bytes to skip
      Returns:
      the actual number of bytes skipped.
      Throws:
      IOException - if an I/O error has occurred
      IllegalArgumentException - if n < 0
      See Also:

    • close

      Closes this input stream and releases any system resources associated with the stream.

      Specified by:
      close in interface AutoCloseable
      Specified by:
      close in interface Closeable
      Overrides:
      close in class FilterInputStream
      Throws:
      IOException - if an I/O error has occurred
      See Also:

    • fill

      Fills input buffer with more data to decompress.

      Implementation Requirements:
      This method will read up to buf.length bytes into the input buffer, buf, starting at element 0. The len field will be set to the number of bytes read.
      Throws:
      IOException - if an I/O error has occurred
      EOFException - if the end of input stream has been reached unexpectedly

    • markSupported

      public boolean markSupported()

      Tests if this input stream supports the mark and reset methods. The markSupported method of InflaterInputStream returns false.

      Overrides:
      markSupported in class FilterInputStream
      Returns:
      a boolean indicating if this stream type supports the mark and reset methods.
      See Also:

    • mark

      public void mark(int readlimit)

      Marks the current position in this input stream.

      Overrides:
      mark in class FilterInputStream
      Implementation Requirements:
      The mark method of InflaterInputStream does nothing.
      Parameters:
      readlimit - the maximum limit of bytes that can be read before the mark position becomes invalid.
      See Also:

    • reset

      Repositions this stream to the position at the time the mark method was last called on this input stream.

      Overrides:
      reset in class FilterInputStream
      Implementation Requirements:
      The method reset for class InflaterInputStream does nothing except throw an IOException.
      Throws:
      IOException - if this method is invoked.
      See Also: