Package org.apache.commons.compress.archivers.zip

Class StreamCompressor

java.lang.Object

org.apache.commons.compress.archivers.zip.StreamCompressor

All Implemented Interfaces:

Closeable, AutoCloseable

public abstract class StreamCompressor
extends Object
implements Closeable

Encapsulates a Deflater and CRC calculator, handling multiple types of output streams. Currently ZipEntry.DEFLATED and ZipEntry.STORED are the only supported compression methods.

Since:

1.10

Method Summary

Modifier and Type	Method	Description
void	close()
static StreamCompressor	create(int compressionLevel, ScatterGatherBackingStore bs)	Creates a stream compressor with the given compression level.
static StreamCompressor	create(ScatterGatherBackingStore bs)	Creates a stream compressor with the default compression level.
void	deflate(InputStream source, int method)	Deflates the given source using the supplied compression method
long	getBytesRead()	Gets the number of bytes read from the source stream
long	getBytesWrittenForLastEntry()	Gets the number of bytes written to the output for the last entry
long	getCrc32()	Gets the CRC-32 of the last deflated file
long	getTotalBytesWritten()	Gets the total number of bytes written to the output for all files
void	writeCounted(byte[] data)	Writes the specified byte array to the output stream.
void	writeCounted(byte[] data, int offset, int length)	Writes len bytes from the specified byte array starting at offset off to the output stream.
protected abstract void	writeOut(byte[] data, int offset, int length)	Writes len bytes from the specified byte array starting at offset off to the output stream.

Methods inherited from class java.lang.Object

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

Method Details

create

public static StreamCompressor create(int compressionLevel,
 ScatterGatherBackingStore bs)

Creates a stream compressor with the given compression level.

Parameters:

compressionLevel - The Deflater compression level

bs - The ScatterGatherBackingStore to receive output

Returns:

A stream compressor

create

public static StreamCompressor create(ScatterGatherBackingStore bs)

Creates a stream compressor with the default compression level.

Parameters:

bs - The ScatterGatherBackingStore to receive output

Returns:

A stream compressor

close

public void close()
           throws IOException

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable

Throws:

IOException

deflate

public void deflate(InputStream source,
 int method)
             throws IOException

Deflates the given source using the supplied compression method

Parameters:

source - The source to compress

method - The #ZipArchiveEntry compression method

Throws:

IOException - When failures happen

getBytesRead

public long getBytesRead()

Gets the number of bytes read from the source stream

Returns:

The number of bytes read, never negative

getBytesWrittenForLastEntry

public long getBytesWrittenForLastEntry()

Gets the number of bytes written to the output for the last entry

Returns:

The number of bytes, never negative

getCrc32

public long getCrc32()

Gets the CRC-32 of the last deflated file

Returns:

the CRC-32

getTotalBytesWritten

public long getTotalBytesWritten()

Gets the total number of bytes written to the output for all files

Returns:

The number of bytes, never negative

writeCounted

public void writeCounted(byte[] data)
                  throws IOException

Writes the specified byte array to the output stream.

Parameters:

data - the data.

Throws:

IOException - if an I/O error occurs.

writeCounted

public void writeCounted(byte[] data,
 int offset,
 int length)
                  throws IOException

Writes len bytes from the specified byte array starting at offset off to the output stream.

Parameters:

data - the data.

offset - the start offset in the data.

length - the number of bytes to write.

Throws:

IOException - if an I/O error occurs.

writeOut

protected abstract void writeOut(byte[] data,
 int offset,
 int length)
                          throws IOException

Writes len bytes from the specified byte array starting at offset off to the output stream.

Parameters:

data - the data.

offset - the start offset in the data.

length - the number of bytes to write.

Throws:

IOException - if an I/O error occurs.