Class JdkZlibEncoder
java.lang.Object
org.jboss.netty.handler.codec.oneone.OneToOneEncoder
org.jboss.netty.handler.codec.oneone.OneToOneStrictEncoder
org.jboss.netty.handler.codec.compression.JdkZlibEncoder
- All Implemented Interfaces:
ChannelDownstreamHandler
,ChannelHandler
,LifeCycleAwareChannelHandler
Compresses a
ChannelBuffer
using the deflate algorithm.-
Nested Class Summary
Nested classes/interfaces inherited from interface org.jboss.netty.channel.ChannelHandler
ChannelHandler.Sharable
-
Field Summary
FieldsModifier and TypeFieldDescriptionprivate final CRC32
private ChannelHandlerContext
private final Deflater
private final AtomicBoolean
private static final byte[]
private byte[]
private final ZlibWrapper
private boolean
-
Constructor Summary
ConstructorsConstructorDescriptionCreates a new zlib encoder with the default compression level (6
) and the default wrapper (ZlibWrapper.ZLIB
).JdkZlibEncoder
(byte[] dictionary) Creates a new zlib encoder with the default compression level (6
) and the specified preset dictionary.JdkZlibEncoder
(int compressionLevel) Creates a new zlib encoder with the specifiedcompressionLevel
and the default wrapper (ZlibWrapper.ZLIB
).JdkZlibEncoder
(int compressionLevel, byte[] dictionary) Creates a new zlib encoder with the specifiedcompressionLevel
and the specified preset dictionary.JdkZlibEncoder
(ZlibWrapper wrapper) Creates a new zlib encoder with the default compression level (6
) and the specified wrapper.JdkZlibEncoder
(ZlibWrapper wrapper, int compressionLevel) Creates a new zlib encoder with the specifiedcompressionLevel
and the specified wrapper. -
Method Summary
Modifier and TypeMethodDescriptionvoid
void
void
void
close()
private void
deflate
(ChannelBuffer out) protected Object
encode
(ChannelHandlerContext ctx, Channel channel, Object msg) Transforms the specified message into another message and return the transformed message.private int
estimateCompressedSize
(int originalSize) private ChannelFuture
finishEncode
(ChannelHandlerContext ctx, ChannelEvent evt) void
Handles the specified downstream event.boolean
isClosed()
private boolean
isGzip()
Methods inherited from class org.jboss.netty.handler.codec.oneone.OneToOneStrictEncoder
doEncode
-
Field Details
-
wrapper
-
deflater
-
finished
-
ctx
-
out
private byte[] out -
crc
-
gzipHeader
private static final byte[] gzipHeader -
writeHeader
private boolean writeHeader
-
-
Constructor Details
-
JdkZlibEncoder
public JdkZlibEncoder()Creates a new zlib encoder with the default compression level (6
) and the default wrapper (ZlibWrapper.ZLIB
).- Throws:
CompressionException
- if failed to initialize zlib
-
JdkZlibEncoder
public JdkZlibEncoder(int compressionLevel) Creates a new zlib encoder with the specifiedcompressionLevel
and the default wrapper (ZlibWrapper.ZLIB
).- Parameters:
compressionLevel
-1
yields the fastest compression and9
yields the best compression.0
means no compression. The default compression level is6
.- Throws:
CompressionException
- if failed to initialize zlib
-
JdkZlibEncoder
Creates a new zlib encoder with the default compression level (6
) and the specified wrapper.- Throws:
CompressionException
- if failed to initialize zlib
-
JdkZlibEncoder
Creates a new zlib encoder with the specifiedcompressionLevel
and the specified wrapper.- Parameters:
compressionLevel
-1
yields the fastest compression and9
yields the best compression.0
means no compression. The default compression level is6
.- Throws:
CompressionException
- if failed to initialize zlib
-
JdkZlibEncoder
public JdkZlibEncoder(byte[] dictionary) Creates a new zlib encoder with the default compression level (6
) and the specified preset dictionary. The wrapper is alwaysZlibWrapper.ZLIB
because it is the only format that supports the preset dictionary.- Parameters:
dictionary
- the preset dictionary- Throws:
CompressionException
- if failed to initialize zlib
-
JdkZlibEncoder
public JdkZlibEncoder(int compressionLevel, byte[] dictionary) Creates a new zlib encoder with the specifiedcompressionLevel
and the specified preset dictionary. The wrapper is alwaysZlibWrapper.ZLIB
because it is the only format that supports the preset dictionary.- Parameters:
compressionLevel
-1
yields the fastest compression and9
yields the best compression.0
means no compression. The default compression level is6
.dictionary
- the preset dictionary- Throws:
CompressionException
- if failed to initialize zlib
-
-
Method Details
-
close
-
isGzip
private boolean isGzip() -
isClosed
public boolean isClosed() -
encode
Description copied from class:OneToOneEncoder
Transforms the specified message into another message and return the transformed message. Note that you can not returnnull
, unlike you can inOneToOneDecoder.decode(ChannelHandlerContext, Channel, Object)
; you must return something, at leastChannelBuffers.EMPTY_BUFFER
.- Specified by:
encode
in classOneToOneEncoder
- Throws:
Exception
-
estimateCompressedSize
private int estimateCompressedSize(int originalSize) -
handleDownstream
Description copied from interface:ChannelDownstreamHandler
Handles the specified downstream event.- Specified by:
handleDownstream
in interfaceChannelDownstreamHandler
- Overrides:
handleDownstream
in classOneToOneEncoder
- Parameters:
ctx
- the context object for this handlerevt
- the downstream event to process or intercept- Throws:
Exception
-
finishEncode
-
deflate
-
beforeAdd
- Specified by:
beforeAdd
in interfaceLifeCycleAwareChannelHandler
- Throws:
Exception
-
afterAdd
- Specified by:
afterAdd
in interfaceLifeCycleAwareChannelHandler
- Throws:
Exception
-
beforeRemove
- Specified by:
beforeRemove
in interfaceLifeCycleAwareChannelHandler
- Throws:
Exception
-
afterRemove
- Specified by:
afterRemove
in interfaceLifeCycleAwareChannelHandler
- Throws:
Exception
-