io.netty.handler.codec.compression

Class Lz4FrameEncoder

java.lang.Object

io.netty.channel.ChannelHandlerAdapter

io.netty.channel.ChannelOutboundHandlerAdapter

io.netty.handler.codec.MessageToByteEncoder<io.netty.buffer.ByteBuf>

io.netty.handler.codec.compression.Lz4FrameEncoder

All Implemented Interfaces:

io.netty.channel.ChannelHandler, io.netty.channel.ChannelOutboundHandler

public class Lz4FrameEncoder
extends MessageToByteEncoder<io.netty.buffer.ByteBuf>

Compresses a ByteBuf using the LZ4 format. See original LZ4 website and LZ4 block format for full description. Since the original LZ4 block format does not contains size of compressed block and size of original data this encoder uses format like LZ4 Java library written by Adrien Grand and approved by Yann Collet (author of original LZ4 library). * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * Magic * Token * Compressed * Decompressed * Checksum * + * LZ4 compressed * * * * length * length * * * block * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *

Nested Class Summary

Nested classes/interfaces inherited from interface io.netty.channel.ChannelHandler

io.netty.channel.ChannelHandler.Sharable

Constructor Summary

Constructors

Constructor and Description
Lz4FrameEncoder() Creates the fastest LZ4 encoder with default block size (64 KB) and xxhash hashing for Java, based on Yann Collet's work available at Google Code.
Lz4FrameEncoder(boolean highCompressor) Creates a new LZ4 encoder with hight or fast compression, default block size (64 KB) and xxhash hashing for Java, based on Yann Collet's work available at Google Code.
Lz4FrameEncoder(net.jpountz.lz4.LZ4Factory factory, boolean highCompressor, int blockSize, Checksum checksum) Creates a new customizable LZ4 encoder.

Method Summary

Methods

Modifier and Type	Method and Description
io.netty.channel.ChannelFuture	close() Close this Lz4FrameEncoder and so finish the encoding.
void	close(io.netty.channel.ChannelHandlerContext ctx, io.netty.channel.ChannelPromise promise)
io.netty.channel.ChannelFuture	close(io.netty.channel.ChannelPromise promise) Close this Lz4FrameEncoder and so finish the encoding.
protected void	encode(io.netty.channel.ChannelHandlerContext ctx, io.netty.buffer.ByteBuf in, io.netty.buffer.ByteBuf out) Encode a message into a ByteBuf.
void	handlerAdded(io.netty.channel.ChannelHandlerContext ctx)
boolean	isClosed() Returns true if and only if the compressed stream has been finished.

Methods inherited from class io.netty.handler.codec.MessageToByteEncoder

acceptOutboundMessage, allocateBuffer, write

Methods inherited from class io.netty.channel.ChannelOutboundHandlerAdapter

bind, connect, deregister, disconnect, flush, read

Methods inherited from class io.netty.channel.ChannelHandlerAdapter

exceptionCaught, handlerRemoved, isSharable

Methods inherited from class java.lang.Object

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

Methods inherited from interface io.netty.channel.ChannelHandler

exceptionCaught, handlerRemoved

Constructor Detail

Lz4FrameEncoder

public Lz4FrameEncoder()

Creates the fastest LZ4 encoder with default block size (64 KB) and xxhash hashing for Java, based on Yann Collet's work available at Google Code.

Lz4FrameEncoder

public Lz4FrameEncoder(boolean highCompressor)

Creates a new LZ4 encoder with hight or fast compression, default block size (64 KB) and xxhash hashing for Java, based on Yann Collet's work available at Google Code.

Parameters:

highCompressor - if true codec will use compressor which requires more memory and is slower but compresses more efficiently

Lz4FrameEncoder

public Lz4FrameEncoder(net.jpountz.lz4.LZ4Factory factory,
               boolean highCompressor,
               int blockSize,
               Checksum checksum)

Creates a new customizable LZ4 encoder.

Parameters:

factory - user customizable LZ4Factory instance which may be JNI bindings to the original C implementation, a pure Java implementation or a Java implementation that uses the sun.misc.Unsafe

highCompressor - if true codec will use compressor which requires more memory and is slower but compresses more efficiently

blockSize - the maximum number of bytes to try to compress at once, must be >= 64 and <= 32 M

checksum - the Checksum instance to use to check data for integrity

Method Detail

encode

protected void encode(io.netty.channel.ChannelHandlerContext ctx,
          io.netty.buffer.ByteBuf in,
          io.netty.buffer.ByteBuf out)
               throws Exception

Description copied from class: MessageToByteEncoder

Encode a message into a ByteBuf. This method will be called for each written message that can be handled by this encoder.

Specified by:

encode in class MessageToByteEncoder<io.netty.buffer.ByteBuf>

Parameters:

ctx - the ChannelHandlerContext which this MessageToByteEncoder belongs to

in - the message to encode

out - the ByteBuf into which the encoded message will be written

Throws:

Exception - is thrown if an error accour

isClosed

public boolean isClosed()

Returns true if and only if the compressed stream has been finished.

close

public io.netty.channel.ChannelFuture close()

Close this Lz4FrameEncoder and so finish the encoding. The returned ChannelFuture will be notified once the operation completes.

close

public io.netty.channel.ChannelFuture close(io.netty.channel.ChannelPromise promise)

Close this Lz4FrameEncoder and so finish the encoding. The given ChannelFuture will be notified once the operation completes and will also be returned.

close

public void close(io.netty.channel.ChannelHandlerContext ctx,
         io.netty.channel.ChannelPromise promise)
           throws Exception

Specified by:

close in interface io.netty.channel.ChannelOutboundHandler

Overrides:

close in class io.netty.channel.ChannelOutboundHandlerAdapter

Throws:

Exception

handlerAdded

public void handlerAdded(io.netty.channel.ChannelHandlerContext ctx)
                  throws Exception

Specified by:

handlerAdded in interface io.netty.channel.ChannelHandler

Overrides:

handlerAdded in class io.netty.channel.ChannelHandlerAdapter

Throws:

Exception