Class DeflaterOutputStream

java.util.zip.DeflaterOutputStream

All Implemented Interfaces:: Closeable, Flushable, AutoCloseable

Direct Known Subclasses:: GZIPOutputStream, ZipOutputStream

public class DeflaterOutputStream extends FilterOutputStream

This class implements an output stream filter for compressing data in the "deflate" compression format. It is also used as the basis for other types of compression filters, such as GZIPOutputStream.

Since:

1.1

See Also:

Deflater

Field Summary

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

Fields declared in class java.io.FilterOutputStream

out

Constructor Summary

Constructor	Description
`DeflaterOutputStream(OutputStream out)`	Creates a new output stream with a default compressor and buffer size.
`DeflaterOutputStream(OutputStream out, boolean syncFlush)`	Creates a new output stream with a default compressor, a default buffer size and the specified flush mode.
`DeflaterOutputStream(OutputStream out, Deflater def)`	Creates a new output stream with the specified compressor and a default buffer size.
`DeflaterOutputStream(OutputStream out, Deflater def, boolean syncFlush)`	Creates a new output stream with the specified compressor, flush mode and a default buffer size.
`DeflaterOutputStream(OutputStream out, Deflater def, int size)`	Creates a new output stream with the specified compressor and buffer size.
`DeflaterOutputStream(OutputStream out, Deflater def, int size, boolean syncFlush)`	Creates a new output stream with the specified compressor, buffer size and flush mode.

Method Summary

Modifier and Type	Method	Description
`void`	`close()`	Writes remaining compressed data to the output stream and closes the underlying stream.
`protected void`	`deflate()`	Writes next block of compressed data to the output stream.
`void`	`finish()`	Finishes writing compressed data to the output stream without closing the underlying stream.
`void`	`flush()`	Flushes the compressed output stream.
`void`	`write(byte[] b, int off, int len)`	Writes an array of bytes to the compressed output stream.
`void`	`write(int b)`	Writes a byte to the compressed output stream.

Methods declared in class java.io.FilterOutputStream

write

Methods declared in class java.io.OutputStream

nullOutputStream

Methods declared in class java.lang.Object

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

Field Details

def

protected Deflater def

Compressor for this stream.

buf

protected byte[] buf

Output buffer for writing compressed data.

Constructor Details

DeflaterOutputStream

public DeflaterOutputStream(OutputStream out, Deflater def, int size, boolean syncFlush)

Creates a new output stream with the specified compressor, buffer size and flush mode.

Parameters:: out - the output stream; def - the compressor ("deflater"); size - the output buffer size; syncFlush - if true the flush() method of this instance flushes the compressor with flush mode Deflater.SYNC_FLUSH before flushing the output stream, otherwise only flushes the output stream
Throws:: IllegalArgumentException - if size <= 0
Since:: 1.7

DeflaterOutputStream

public DeflaterOutputStream(OutputStream out, Deflater def, int size)

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

The new output stream instance is created as if by invoking the 4-argument constructor DeflaterOutputStream(out, def, size, false).

Parameters:: out - the output stream; def - the compressor ("deflater"); size - the output buffer size
Throws:: IllegalArgumentException - if size <= 0

DeflaterOutputStream

public DeflaterOutputStream(OutputStream out, Deflater def, boolean syncFlush)

Creates a new output stream with the specified compressor, flush mode and a default buffer size.

Parameters:: out - the output stream; def - the compressor ("deflater"); syncFlush - if true the flush() method of this instance flushes the compressor with flush mode Deflater.SYNC_FLUSH before flushing the output stream, otherwise only flushes the output stream
Since:: 1.7

DeflaterOutputStream

public DeflaterOutputStream(OutputStream out, Deflater def)

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

The new output stream instance is created as if by invoking the 3-argument constructor DeflaterOutputStream(out, def, false).

Parameters:: out - the output stream; def - the compressor ("deflater")

DeflaterOutputStream

public DeflaterOutputStream(OutputStream out, boolean syncFlush)

Creates a new output stream with a default compressor, a default buffer size and the specified flush mode.

Parameters:: out - the output stream; syncFlush - if true the flush() method of this instance flushes the compressor with flush mode Deflater.SYNC_FLUSH before flushing the output stream, otherwise only flushes the output stream
Since:: 1.7

DeflaterOutputStream

public DeflaterOutputStream(OutputStream out)

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

The new output stream instance is created as if by invoking the 2-argument constructor DeflaterOutputStream(out, false).

Parameters:: out - the output stream

Method Details

write

public void write(int b) throws IOException

Writes a byte to the compressed output stream. This method will block until the byte can be written.

Overrides:: write in class FilterOutputStream
Parameters:: b - the byte to be written
Throws:: IOException - if an I/O error has occurred

write

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

Writes an array of bytes to the compressed output stream. This method will block until all the bytes are written.

Overrides:

write in class FilterOutputStream

Parameters:

b - the data to be written

off - the start offset of the data

len - the length of the data

Throws:

IOException - if an I/O error has occurred

See Also:

FilterOutputStream.write(int)

finish

public void finish() throws IOException

Finishes writing compressed data to the output stream without closing the underlying stream. Use this method when applying multiple filters in succession to the same output stream.

Throws:: IOException - if an I/O error has occurred

close

public void close() throws IOException

Writes remaining compressed data to the output stream and closes the underlying stream.

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable

Overrides:

close in class FilterOutputStream

Throws:

IOException - if an I/O error has occurred

See Also:

deflate

protected void deflate() throws IOException

Writes next block of compressed data to the output stream.

Throws:: IOException - if an I/O error has occurred

flush

public void flush() throws IOException

Flushes the compressed output stream. If syncFlush is true when this compressed output stream is constructed, this method first flushes the underlying compressor with the flush mode Deflater.SYNC_FLUSH to force all pending data to be flushed out to the output stream and then flushes the output stream. Otherwise this method only flushes the output stream without flushing the compressor.

Specified by:

flush in interface Flushable

Overrides:

flush in class FilterOutputStream

Throws:

IOException - if an I/O error has occurred

Since:

1.7

See Also:

FilterOutputStream.out

© 1993, 2021, Oracle and/or its affiliates. All rights reserved.
Documentation extracted from Debian's OpenJDK Development Kit package.
Licensed under the GNU General Public License, version 2, with the Classpath Exception.
Various third party code in OpenJDK is licensed under different licenses (see Debian package).
Java and OpenJDK are trademarks or registered trademarks of Oracle and/or its affiliates.
https://docs.oracle.com/en/java/javase/17/docs/api/java.base/java/util/zip/DeflaterOutputStream.html