java.util.zip
Class InflaterInputStream

java.lang.Object
  java.io.InputStream
      java.io.FilterInputStream
          java.util.zip.InflaterInputStream

Direct Known Subclasses:

GZIPInputStream, ZipInputStream

public class InflaterInputStream

extends FilterInputStream

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.

Author:

David Connelly

See Also:

Inflater

Field Summary

private byte[]	b
protected byte[]	buf Input buffer for decompression.
private boolean	closed
protected Inflater	inf Decompressor for this stream.
protected int	len Length of input buffer.
private boolean	reachEOF
private byte[]	singleByteBuf
(package private) boolean	usesDefaultInflater

Fields inherited from class java.io.FilterInputStream

in

Fields inherited from class java.io.InputStream

Constructor Summary

InflaterInputStream(InputStream in)
Creates a new input stream with a default decompressor and buffer size.

InflaterInputStream(InputStream in, Inflater inf)
Creates a new input stream with the specified decompressor and a default buffer size.

InflaterInputStream(InputStream in, Inflater inf, int size)
Creates a new input stream with the specified decompressor and buffer size.

Method Summary

int	available() Returns 0 after EOF has reached, otherwise always return 1.
void	close() Closes the input stream.
private void	ensureOpen() Check to make sure that this stream has not been closed
protected void	fill() Fills input buffer with more data to decompress.
int	read() Reads a byte of uncompressed data.
int	read(byte[] b, int off, int len) Reads uncompressed data into an array of bytes.
long	skip(long n) Skips specified number of bytes of uncompressed data.

Methods inherited from class java.io.FilterInputStream

mark, markSupported, read, reset

Methods inherited from class java.lang.Object

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

Field Detail

inf

protected Inflater inf

Decompressor for this stream.

buf

protected byte[] buf

Input buffer for decompression.

len

protected int len

Length of input buffer.

closed

private boolean closed

reachEOF

private boolean reachEOF

usesDefaultInflater

boolean usesDefaultInflater

singleByteBuf

private byte[] singleByteBuf

b

private byte[] b

Constructor Detail

InflaterInputStream

public InflaterInputStream(InputStream in,
                           Inflater inf,
                           int size)

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 is <= 0

InflaterInputStream

public InflaterInputStream(InputStream in,
                           Inflater inf)

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

Parameters:

in - the input stream

inf - the decompressor ("inflater")

InflaterInputStream

public InflaterInputStream(InputStream in)

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

Parameters:

in - the input stream

Method Detail

ensureOpen

private void ensureOpen()
                 throws IOException

Check to make sure that this stream has not been closed

Throws:

IOException

read

public int read()
         throws IOException

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:

FilterInputStream.in

read

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

Reads uncompressed data into an array of bytes. This method will block until some input can be decompressed.

Overrides:

read in class FilterInputStream

Parameters:

b - the buffer into which the data is read

off - the start offset of the data

len - the maximum number of bytes read

Returns:

the actual number of bytes read, or -1 if the end of the compressed input is reached or a preset dictionary is needed

Throws:

ZipException - if a ZIP format error has occurred

IOException - if an I/O error has occurred

See Also:

FilterInputStream.in

available

public int available()
              throws IOException

Returns 0 after EOF has 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.

See Also:

FilterInputStream.in

skip

public long skip(long n)
          throws IOException

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

close

public void close()
           throws IOException

Closes the input stream.

Overrides:

close in class FilterInputStream

Throws:

IOException - if an I/O error has occurred

See Also:

FilterInputStream.in

fill

protected void fill()
             throws IOException

Fills input buffer with more data to decompress.

Throws:

IOException - if an I/O error has occurred