Class DeflaterInputStream

java.lang.Object
- java.io.InputStream
- - java.io.FilterInputStream
  - - java.util.zip.DeflaterInputStream

All Implemented Interfaces:: Closeable, AutoCloseable

public class DeflaterInputStream
extends FilterInputStream

Implements an input stream filter for compressing data in the "deflate" compression format.

Since:: 1.6
See Also:: DeflaterOutputStream, InflaterOutputStream, InflaterInputStream

Field Summary

Fields
Modifier and Type	Field	Description
`protected byte[]`	`buf`	Input buffer for reading compressed data.
`protected Deflater`	`def`	Compressor for this stream.

Fields declared in class java.io.FilterInputStream

in

Constructor Summary

Constructors
Constructor	Description
`DeflaterInputStream(InputStream in)`	Creates a new input stream with a default compressor and buffer size.
`DeflaterInputStream(InputStream in, Deflater defl)`	Creates a new input stream with the specified compressor and a default buffer size.
`DeflaterInputStream(InputStream in, Deflater defl, int bufLen)`	Creates a new input stream with the specified compressor and buffer size.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`int`	`available()`	Returns 0 after EOF has been reached, otherwise always return 1.
`void`	`close()`	Closes this input stream and its underlying input stream, discarding any pending uncompressed data.
`void`	`mark(int limit)`	This operation is not supported.
`boolean`	`markSupported()`	Always returns `false` because this input stream does not support the `mark()` and `reset()` methods.
`int`	`read()`	Reads a single byte of compressed data from the input stream.
`int`	`read(byte[] b, int off, int len)`	Reads compressed data into a byte array.
`void`	`reset()`	This operation is not supported.
`long`	`skip(long n)`	Skips over and discards data from the input stream.

Methods declared in class java.io.FilterInputStream

read

Methods declared in class java.io.InputStream

nullInputStream, readAllBytes, readNBytes, readNBytes, transferTo

Methods declared in class java.lang.Object

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

Field Detail

def

protected final Deflater def

Compressor for this stream.

buf

protected final byte[] buf

Input buffer for reading compressed data.

Constructor Detail

DeflaterInputStream

public DeflaterInputStream(InputStream in)

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

Parameters:: in - input stream to read the uncompressed data to
Throws:: NullPointerException - if in is null

DeflaterInputStream

public DeflaterInputStream(InputStream in,
                           Deflater defl)

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

Parameters:: in - input stream to read the uncompressed data to; defl - compressor ("deflater") for this stream
Throws:: NullPointerException - if in or defl is null

DeflaterInputStream

public DeflaterInputStream(InputStream in,
                           Deflater defl,
                           int bufLen)

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

Parameters:: in - input stream to read the uncompressed data to; defl - compressor ("deflater") for this stream; bufLen - compression buffer size
Throws:: IllegalArgumentException - if bufLen <= 0; NullPointerException - if in or defl is null

Method Detail

close

public void close()
           throws IOException

Closes this input stream and its underlying input stream, discarding any pending uncompressed data.

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

read

public int read()
         throws IOException

Reads a single byte of compressed data from the input stream. This method will block until some input can be read and compressed.

Overrides:: read in class FilterInputStream
Returns:: a single byte of compressed data, or -1 if the end of the uncompressed input stream is reached
Throws:: IOException - if an I/O error occurs or if this stream is already closed
See Also:: FilterInputStream.in

read

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

Reads compressed data into a byte array. This method will block until some input can be read and compressed.

Overrides:: read in class FilterInputStream
Parameters:: b - buffer into which the data is read; off - starting offset of the data within b; len - maximum number of compressed bytes to read into b
Returns:: the actual number of bytes read, or -1 if the end of the uncompressed input stream is reached
Throws:: IndexOutOfBoundsException - if len > b.length - off; IOException - if an I/O error occurs or if this input stream is already closed
See Also:: FilterInputStream.in

skip

public long skip(long n)
          throws IOException

Skips over and discards data from the input stream. This method may block until the specified number of bytes are read and skipped. Note: While n is given as a long, the maximum number of bytes which can be skipped is Integer.MAX_VALUE.

Overrides:: skip in class FilterInputStream
Parameters:: n - number of bytes to be skipped
Returns:: the actual number of bytes skipped
Throws:: IOException - if an I/O error occurs or if this stream is already closed

available

public int available()
              throws IOException

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:: zero after the end of the underlying input stream has been reached, otherwise always returns 1
Throws:: IOException - if an I/O error occurs or if this stream is already closed

markSupported

public boolean markSupported()

Always returns false because this input stream does not support the mark() and reset() methods.

Overrides:: markSupported in class FilterInputStream
Returns:: false, always
See Also:: FilterInputStream.in, InputStream.mark(int), InputStream.reset()

mark

public void mark(int limit)

This operation is not supported.

Overrides:: mark in class FilterInputStream
Parameters:: limit - maximum bytes that can be read before invalidating the position marker
See Also:: FilterInputStream.in, FilterInputStream.reset()

reset

public void reset()
           throws IOException

This operation is not supported.

Overrides:: reset in class FilterInputStream
Throws:: IOException - always thrown
See Also:: FilterInputStream.in, FilterInputStream.mark(int)