java.util.zip

Class DeflaterOutputStream

java.lang.Object

java.io.OutputStream

java.io.FilterOutputStream

java.util.zip.DeflaterOutputStream

Direct Known Subclasses:

GZIPOutputStream, ZipOutputStream

public class DeflaterOutputStream
extends FilterOutputStream

This is a special FilterOutputStream deflating the bytes that are written through it. It uses the Deflater for deflating. A special thing to be noted is that flush() doesn't flush everything in Sun's JDK, but it does so in jazzlib. This is because Sun's Deflater doesn't have a way to flush() everything, without finishing the stream.

Author:

Tom Tromey, Jochen Hoenicke

Field Summary

Fields

Modifier and Type	Field and Description
protected byte[]	buf This buffer is used temporarily to retrieve the bytes from the deflater and write them to the underlying output stream.
protected Deflater	def The deflater which is used to deflate the stream.

Fields inherited from class java.io.FilterOutputStream

out

Constructor Summary

Constructors

Constructor and Description
DeflaterOutputStream(OutputStream out) Creates a new DeflaterOutputStream with a default Deflater and default buffer size.
DeflaterOutputStream(OutputStream out, Deflater defl) Creates a new DeflaterOutputStream with the given Deflater and default buffer size.
DeflaterOutputStream(OutputStream out, Deflater defl, int bufsize) Creates a new DeflaterOutputStream with the given Deflater and buffer size.

Method Summary

Modifier and Type	Method and Description
void	close() Calls finish () and closes the stream.
protected void	deflate() Deflates everything in the def's input buffers.
void	finish() Finishes the stream by calling finish() on the deflater.
void	flush() Flushes the stream by calling flush() on the deflater and then on the underlying stream.
void	write(byte[] buf, int off, int len) Writes a len bytes from an array to the compressed stream.
void	write(int bval) Writes a single byte to the compressed output stream.

Methods inherited from class java.io.FilterOutputStream

write

Methods inherited from class java.io.OutputStream

finalize

Methods inherited from class java.lang.Object

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

Field Detail

buf

protected byte[] buf

This buffer is used temporarily to retrieve the bytes from the deflater and write them to the underlying output stream.

def

protected Deflater def

The deflater which is used to deflate the stream.

Constructor Detail

DeflaterOutputStream

public DeflaterOutputStream(OutputStream out)

Creates a new DeflaterOutputStream with a default Deflater and default buffer size.

Parameters:

out - the output stream where deflated output should be written.

DeflaterOutputStream

public DeflaterOutputStream(OutputStream out,
                            Deflater defl)

Creates a new DeflaterOutputStream with the given Deflater and default buffer size.

Parameters:

out - the output stream where deflated output should be written.

defl - the underlying deflater.

DeflaterOutputStream

public DeflaterOutputStream(OutputStream out,
                            Deflater defl,
                            int bufsize)

Creates a new DeflaterOutputStream with the given Deflater and buffer size.

Parameters:

out - the output stream where deflated output should be written.

defl - the underlying deflater.

bufsize - the buffer size.

Throws:

IllegalArgumentException - if bufsize isn't positive.

Method Detail

deflate

protected void deflate()
                throws IOException

Deflates everything in the def's input buffers. This will call def.deflate() until all bytes from the input buffers are processed.

Throws:

IOException

flush

public void flush()
           throws IOException

Flushes the stream by calling flush() on the deflater and then on the underlying stream. This ensures that all bytes are flushed. This function doesn't work in Sun's JDK, but only in jazzlib.

Overrides:

flush in class FilterOutputStream

Throws:

IOException - If an error occurs

finish

public void finish()
            throws IOException

Finishes the stream by calling finish() on the deflater. This was the only way to ensure that all bytes are flushed in Sun's JDK.

Throws:

IOException

close

public void close()
           throws IOException

Calls finish () and closes the stream.

Overrides:

close in class FilterOutputStream

Throws:

IOException - If an error occurs

write

public void write(int bval)
           throws IOException

Writes a single byte to the compressed output stream.

Overrides:

write in class FilterOutputStream

Parameters:

bval - the byte value.

Throws:

IOException - If an error occurs

write

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

Writes a len bytes from an array to the compressed stream.

Overrides:

write in class FilterOutputStream

Parameters:

buf - the byte array.

off - the offset into the byte array where to start.

len - the number of bytes to write.

Throws:

IOException - If an error occurs