org.dellroad.lzma.client

Class LZMACompressor

java.lang.Object

org.dellroad.lzma.client.LZMACompressor

All Implemented Interfaces:

com.google.gwt.core.client.Scheduler.RepeatingCommand

Direct Known Subclasses:

LZMAByteArrayCompressor

public class LZMACompressor
extends Object
implements com.google.gwt.core.client.Scheduler.RepeatingCommand

LZMA compressor.

Field Summary

Fields

Modifier and Type	Field and Description
static CompressionMode	DEFAULT_COMPRESSION_MODE The default compression mode (3).

Constructor Summary

Constructors

Constructor and Description
LZMACompressor(InputStream input, OutputStream output) Construct an encoder with unknown input length and using the default compression mode.
LZMACompressor(InputStream input, OutputStream output, long length) Construct an encoder with unknown using the default compression mode.
LZMACompressor(InputStream input, OutputStream output, long length, CompressionMode mode) Primary constructor.

Method Summary

Modifier and Type	Method and Description
boolean	execute() Process the next chunk of data.
IOException	getException() Get the exception thrown during the previous execution round, if any.
double	getProgress() Determine how much of the input data has been compressed so far.

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_COMPRESSION_MODE

public static final CompressionMode DEFAULT_COMPRESSION_MODE

The default compression mode (3).

Constructor Detail

LZMACompressor

public LZMACompressor(InputStream input,
                      OutputStream output)
               throws IOException

Construct an encoder with unknown input length and using the default compression mode.

This is a convenience constructor, equivalent to:

LZMACompressor(input, output, -1, DEFAULT_COMPRESSION_MODE)

Throws:

IOException

LZMACompressor

public LZMACompressor(InputStream input,
                      OutputStream output,
                      long length)
               throws IOException

Construct an encoder with unknown using the default compression mode.

This is a convenience constructor, equivalent to:

LZMACompressor(input, output, length, DEFAULT_COMPRESSION_MODE)

Throws:

IOException

LZMACompressor

public LZMACompressor(InputStream input,
                      OutputStream output,
                      long length,
                      CompressionMode mode)
               throws IOException

Primary constructor.

The given length limits how much data will be read from the input and will be encoded at the beginning of the compressed output. This allows decompressors to determine the uncompressed length without having to decompress the entire content, and causes the decompressor to stop decompressing at that point. If the length is not known, -1 should be used.

The input and output streams will not be closed when the operation completes.

Parameters:

input - uncompressed input

output - compressed output

length - length of the input data if known, otherwise -1

mode - compression mode

Throws:

IllegalArgumentException - if length is less than -1

IllegalArgumentException - if mode is null

IOException - if input or output does

Method Detail

execute

public boolean execute()

Process the next chunk of data. If an IOException is thrown during processing, this returns false and getException() will return the caught exception.

Specified by:

execute in interface com.google.gwt.core.client.Scheduler.RepeatingCommand

Returns:

true if there is more work to do, otherwise false

Throws:

IllegalStateException - if this compression operation has already completed

getProgress

public double getProgress()

Determine how much of the input data has been compressed so far. If a length of -1 was given to the constructor, then this always returns zero.

Returns:

a value from 0.0 to 1.0

getException

public IOException getException()

Get the exception thrown during the previous execution round, if any. Note: this method must be checked after compression is complete to determine if there was an error.

Returns:

thrown exception, or null if none was ever thrown