io.netty.handler.codec.http

类 HttpObjectDecoder

java.lang.Object

io.netty.channel.ChannelHandlerAdapter

io.netty.channel.ChannelInboundHandlerAdapter

io.netty.handler.codec.ByteToMessageDecoder

io.netty.handler.codec.http.HttpObjectDecoder

所有已实现的接口:

ChannelHandler, ChannelInboundHandler

直接已知子类:

HttpRequestDecoder, HttpResponseDecoder, RtspDecoder, RtspObjectDecoder

public abstract class HttpObjectDecoder
extends ByteToMessageDecoder

Decodes ByteBufs into HttpMessages and HttpContents.

Parameters that prevents excessive memory consumption

Name	Meaning
maxInitialLineLength	The maximum length of the initial line (e.g. "GET / HTTP/1.0" or "HTTP/1.0 200 OK") If the length of the initial line exceeds this value, a TooLongFrameException will be raised.
maxHeaderSize	The maximum length of all headers. If the sum of the length of each header exceeds this value, a TooLongFrameException will be raised.
maxChunkSize	The maximum length of the content or each chunk. If the content length (or the length of each chunk) exceeds this value, the content or chunk will be split into multiple HttpContents whose length is maxChunkSize at maximum.

Chunked Content

If the content of an HTTP message is greater than maxChunkSize or the transfer encoding of the HTTP message is 'chunked', this decoder generates one HttpMessage instance and its following HttpContents per single HTTP message to avoid excessive memory consumption. For example, the following HTTP message:

 GET / HTTP/1.1
 Transfer-Encoding: chunked

 1a
 abcdefghijklmnopqrstuvwxyz
 10
 1234567890abcdef
 0
 Content-MD5: ...
 [blank line]
 

triggers HttpRequestDecoder to generate 3 objects:

1. An HttpRequest,
2. The first HttpContent whose content is 'abcdefghijklmnopqrstuvwxyz',
3. The second LastHttpContent whose content is '1234567890abcdef', which marks the end of the content.

If you prefer not to handle HttpContents by yourself for your convenience, insert HttpObjectAggregator after this decoder in the ChannelPipeline. However, please note that your server might not be as memory efficient as without the aggregator.

Extensibility

Please note that this decoder is designed to be extended to implement a protocol derived from HTTP, such as RTSP and ICAP. To implement the decoder of such a derived protocol, extend this class and implement all abstract methods properly.

嵌套类概要

从类继承的嵌套类/接口 io.netty.handler.codec.ByteToMessageDecoder

ByteToMessageDecoder.Cumulator

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

ChannelHandler.Sharable

字段概要

字段

限定符和类型	字段和说明
protected boolean	validateHeaders

从类继承的字段 io.netty.handler.codec.ByteToMessageDecoder

COMPOSITE_CUMULATOR, MERGE_CUMULATOR

构造器概要

构造器

限定符	构造器和说明
protected	HttpObjectDecoder() Creates a new instance with the default maxInitialLineLength (4096}, maxHeaderSize (8192), and maxChunkSize (8192).
protected	HttpObjectDecoder(int maxInitialLineLength, int maxHeaderSize, int maxChunkSize, boolean chunkedSupported) Creates a new instance with the specified parameters.
protected	HttpObjectDecoder(int maxInitialLineLength, int maxHeaderSize, int maxChunkSize, boolean chunkedSupported, boolean validateHeaders) Creates a new instance with the specified parameters.
protected	HttpObjectDecoder(int maxInitialLineLength, int maxHeaderSize, int maxChunkSize, boolean chunkedSupported, boolean validateHeaders, int initialBufferSize)

方法概要

方法

限定符和类型	方法和说明
protected abstract HttpMessage	createInvalidMessage()
protected abstract HttpMessage	createMessage(java.lang.String[] initialLine)
protected void	decode(ChannelHandlerContext ctx, ByteBuf buffer, java.util.List<java.lang.Object> out) Decode the from one ByteBuf to an other.
protected void	decodeLast(ChannelHandlerContext ctx, ByteBuf in, java.util.List<java.lang.Object> out) Is called one last time when the ChannelHandlerContext goes in-active.
protected boolean	isContentAlwaysEmpty(HttpMessage msg)
protected abstract boolean	isDecodingRequest()
protected boolean	isSwitchingToNonHttp1Protocol(HttpResponse msg) Returns true if the server switched to a different protocol than HTTP/1.0 or HTTP/1.1, e.g.
void	reset() Resets the state of the decoder so that it is ready to decode a new message.
void	userEventTriggered(ChannelHandlerContext ctx, java.lang.Object evt) Calls ChannelHandlerContext.fireUserEventTriggered(Object) to forward to the next ChannelInboundHandler in the ChannelPipeline.

从类继承的方法 io.netty.handler.codec.ByteToMessageDecoder

actualReadableBytes, callDecode, channelInactive, channelRead, channelReadComplete, discardSomeReadBytes, handlerRemoved, handlerRemoved0, internalBuffer, isSingleDecode, setCumulator, setDiscardAfterReads, setSingleDecode

从类继承的方法 io.netty.channel.ChannelInboundHandlerAdapter

channelActive, channelRegistered, channelUnregistered, channelWritabilityChanged, exceptionCaught

从类继承的方法 io.netty.channel.ChannelHandlerAdapter

ensureNotSharable, handlerAdded, isSharable

从类继承的方法 java.lang.Object

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

从接口继承的方法 io.netty.channel.ChannelHandler

handlerAdded

字段详细资料

validateHeaders

protected final boolean validateHeaders

构造器详细资料

HttpObjectDecoder

protected HttpObjectDecoder()

Creates a new instance with the default maxInitialLineLength (4096}, maxHeaderSize (8192), and maxChunkSize (8192).

HttpObjectDecoder

protected HttpObjectDecoder(int maxInitialLineLength,
                 int maxHeaderSize,
                 int maxChunkSize,
                 boolean chunkedSupported)

Creates a new instance with the specified parameters.

HttpObjectDecoder

protected HttpObjectDecoder(int maxInitialLineLength,
                 int maxHeaderSize,
                 int maxChunkSize,
                 boolean chunkedSupported,
                 boolean validateHeaders)

Creates a new instance with the specified parameters.

HttpObjectDecoder

protected HttpObjectDecoder(int maxInitialLineLength,
                 int maxHeaderSize,
                 int maxChunkSize,
                 boolean chunkedSupported,
                 boolean validateHeaders,
                 int initialBufferSize)

方法详细资料

decode

protected void decode(ChannelHandlerContext ctx,
          ByteBuf buffer,
          java.util.List<java.lang.Object> out)
               throws java.lang.Exception

从类复制的说明: ByteToMessageDecoder

Decode the from one ByteBuf to an other. This method will be called till either the input ByteBuf has nothing to read when return from this method or till nothing was read from the input ByteBuf.

指定者:

decode 在类中 ByteToMessageDecoder

参数:

ctx - the ChannelHandlerContext which this ByteToMessageDecoder belongs to

buffer - the ByteBuf from which to read data

out - the List to which decoded messages should be added

抛出:

java.lang.Exception - is thrown if an error occurs

decodeLast

protected void decodeLast(ChannelHandlerContext ctx,
              ByteBuf in,
              java.util.List<java.lang.Object> out)
                   throws java.lang.Exception

从类复制的说明: ByteToMessageDecoder

Is called one last time when the ChannelHandlerContext goes in-active. Which means the ByteToMessageDecoder.channelInactive(ChannelHandlerContext) was triggered. By default this will just call ByteToMessageDecoder.decode(ChannelHandlerContext, ByteBuf, List) but sub-classes may override this for some special cleanup operation.

覆盖:

decodeLast 在类中 ByteToMessageDecoder

抛出:

java.lang.Exception

userEventTriggered

public void userEventTriggered(ChannelHandlerContext ctx,
                      java.lang.Object evt)
                        throws java.lang.Exception

从类复制的说明: ChannelInboundHandlerAdapter

Calls ChannelHandlerContext.fireUserEventTriggered(Object) to forward to the next ChannelInboundHandler in the ChannelPipeline. Sub-classes may override this method to change behavior.

指定者:

userEventTriggered 在接口中 ChannelInboundHandler

覆盖:

userEventTriggered 在类中 ByteToMessageDecoder

抛出:

java.lang.Exception

isContentAlwaysEmpty

protected boolean isContentAlwaysEmpty(HttpMessage msg)

isSwitchingToNonHttp1Protocol

protected boolean isSwitchingToNonHttp1Protocol(HttpResponse msg)

Returns true if the server switched to a different protocol than HTTP/1.0 or HTTP/1.1, e.g. HTTP/2 or Websocket. Returns false if the upgrade happened in a different layer, e.g. upgrade from HTTP/1.1 to HTTP/1.1 over TLS.

reset

public void reset()

Resets the state of the decoder so that it is ready to decode a new message. This method is useful for handling a rejected request with Expect: 100-continue header.

isDecodingRequest

protected abstract boolean isDecodingRequest()

createMessage

protected abstract HttpMessage createMessage(java.lang.String[] initialLine)
                                      throws java.lang.Exception

抛出:

java.lang.Exception

createInvalidMessage

protected abstract HttpMessage createInvalidMessage()