org.jboss.netty.handler.codec.frame

类 DelimiterBasedFrameDecoder

java.lang.Object

org.jboss.netty.channel.SimpleChannelUpstreamHandler

org.jboss.netty.handler.codec.frame.FrameDecoder

org.jboss.netty.handler.codec.frame.DelimiterBasedFrameDecoder

所有已实现的接口:

ChannelHandler, ChannelUpstreamHandler, LifeCycleAwareChannelHandler

public class DelimiterBasedFrameDecoder
extends FrameDecoder

A decoder that splits the received ChannelBuffers by one or more delimiters. It is particularly useful for decoding the frames which ends with a delimiter such as NUL or newline characters.

Predefined delimiters

Delimiters defines frequently used delimiters for convenience' sake.

Specifying more than one delimiter

DelimiterBasedFrameDecoder allows you to specify more than one delimiter. If more than one delimiter is found in the buffer, it chooses the delimiter which produces the shortest frame. For example, if you have the following data in the buffer:

 +--------------+
 | ABC\nDEF\r\n |
 +--------------+
 

a DelimiterBasedFrameDecoder(Delimiters.lineDelimiter()) will choose '\n' as the first delimiter and produce two frames:

 +-----+-----+
 | ABC | DEF |
 +-----+-----+
 

rather than incorrectly choosing '\r\n' as the first delimiter:

 +----------+
 | ABC\nDEF |
 +----------+
 

嵌套类概要

从接口继承的嵌套类/接口 org.jboss.netty.channel.ChannelHandler

ChannelHandler.Sharable

字段概要

从类继承的字段 org.jboss.netty.handler.codec.frame.FrameDecoder

cumulation, DEFAULT_MAX_COMPOSITEBUFFER_COMPONENTS

构造器概要

构造器

构造器和说明
DelimiterBasedFrameDecoder(int maxFrameLength, boolean stripDelimiter, boolean failFast, ChannelBuffer... delimiters) Creates a new instance.
DelimiterBasedFrameDecoder(int maxFrameLength, boolean stripDelimiter, boolean failFast, ChannelBuffer delimiter) Creates a new instance.
DelimiterBasedFrameDecoder(int maxFrameLength, boolean stripDelimiter, ChannelBuffer... delimiters) Creates a new instance.
DelimiterBasedFrameDecoder(int maxFrameLength, boolean stripDelimiter, ChannelBuffer delimiter) Creates a new instance.
DelimiterBasedFrameDecoder(int maxFrameLength, ChannelBuffer... delimiters) Creates a new instance.
DelimiterBasedFrameDecoder(int maxFrameLength, ChannelBuffer delimiter) Creates a new instance.

方法概要

方法

限定符和类型	方法和说明
protected java.lang.Object	decode(ChannelHandlerContext ctx, Channel channel, ChannelBuffer buffer) Decodes the received packets so far into a frame.

从类继承的方法 org.jboss.netty.handler.codec.frame.FrameDecoder

actualReadableBytes, afterAdd, afterRemove, appendToCumulation, beforeAdd, beforeRemove, channelClosed, channelDisconnected, cleanup, decodeLast, exceptionCaught, extractFrame, getMaxCumulationBufferCapacity, getMaxCumulationBufferComponents, internalBuffer, isUnfold, messageReceived, newCumulationBuffer, replace, setMaxCumulationBufferCapacity, setMaxCumulationBufferComponents, setUnfold, unfoldAndFireMessageReceived, updateCumulation

从类继承的方法 org.jboss.netty.channel.SimpleChannelUpstreamHandler

channelBound, channelConnected, channelInterestChanged, channelOpen, channelUnbound, childChannelClosed, childChannelOpen, handleUpstream, writeComplete

从类继承的方法 java.lang.Object

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

构造器详细资料

DelimiterBasedFrameDecoder

public DelimiterBasedFrameDecoder(int maxFrameLength,
                          ChannelBuffer delimiter)

Creates a new instance.

参数:

maxFrameLength - the maximum length of the decoded frame. A TooLongFrameException is thrown if the length of the frame exceeds this value.

delimiter - the delimiter

DelimiterBasedFrameDecoder

public DelimiterBasedFrameDecoder(int maxFrameLength,
                          boolean stripDelimiter,
                          ChannelBuffer delimiter)

Creates a new instance.

参数:

maxFrameLength - the maximum length of the decoded frame. A TooLongFrameException is thrown if the length of the frame exceeds this value.

stripDelimiter - whether the decoded frame should strip out the delimiter or not

delimiter - the delimiter

DelimiterBasedFrameDecoder

public DelimiterBasedFrameDecoder(int maxFrameLength,
                          boolean stripDelimiter,
                          boolean failFast,
                          ChannelBuffer delimiter)

Creates a new instance.

参数:

maxFrameLength - the maximum length of the decoded frame. A TooLongFrameException is thrown if the length of the frame exceeds this value.

stripDelimiter - whether the decoded frame should strip out the delimiter or not

failFast - If true, a TooLongFrameException is thrown as soon as the decoder notices the length of the frame will exceed maxFrameLength regardless of whether the entire frame has been read. If false, a TooLongFrameException is thrown after the entire frame that exceeds maxFrameLength has been read.

delimiter - the delimiter

DelimiterBasedFrameDecoder

public DelimiterBasedFrameDecoder(int maxFrameLength,
                          ChannelBuffer... delimiters)

Creates a new instance.

参数:

maxFrameLength - the maximum length of the decoded frame. A TooLongFrameException is thrown if the length of the frame exceeds this value.

delimiters - the delimiters

DelimiterBasedFrameDecoder

public DelimiterBasedFrameDecoder(int maxFrameLength,
                          boolean stripDelimiter,
                          ChannelBuffer... delimiters)

Creates a new instance.

参数:

maxFrameLength - the maximum length of the decoded frame. A TooLongFrameException is thrown if the length of the frame exceeds this value.

stripDelimiter - whether the decoded frame should strip out the delimiter or not

delimiters - the delimiters

DelimiterBasedFrameDecoder

public DelimiterBasedFrameDecoder(int maxFrameLength,
                          boolean stripDelimiter,
                          boolean failFast,
                          ChannelBuffer... delimiters)

Creates a new instance.

参数:

maxFrameLength - the maximum length of the decoded frame. A TooLongFrameException is thrown if the length of the frame exceeds this value.

stripDelimiter - whether the decoded frame should strip out the delimiter or not

failFast - If true, a TooLongFrameException is thrown as soon as the decoder notices the length of the frame will exceed maxFrameLength regardless of whether the entire frame has been read. If false, a TooLongFrameException is thrown after the entire frame that exceeds maxFrameLength has been read.

delimiters - the delimiters

方法详细资料

decode

protected java.lang.Object decode(ChannelHandlerContext ctx,
                      Channel channel,
                      ChannelBuffer buffer)
                           throws java.lang.Exception

从类复制的说明: FrameDecoder

Decodes the received packets so far into a frame. If an sub-class wants to extract a frame out of the buffer it should use the FrameDecoder.extractFrame(ChannelBuffer, int, int) method, to make optimizations easier later.

指定者:

decode 在类中 FrameDecoder

参数:

ctx - the context of this handler

channel - the current channel

buffer - the cumulative buffer of received packets so far. Note that the buffer might be empty, which means you should not make an assumption that the buffer contains at least one byte in your decoder implementation.

返回:

the decoded frame if a full frame was received and decoded. null if there's not enough data in the buffer to decode a frame.

抛出:

java.lang.Exception