Netty/Codec/HTTP 4.1.107.Final · io.netty.handler.codec.http.HttpServerKeepAliveHandler

HttpServerKeepAliveHandler helps close persistent connections when appropriate.

The server channel is expected to set the proper 'Connection' header if it can handle persistent connections. HttpServerKeepAliveHandler will automatically close the channel for any LastHttpContent that corresponds to a client request for closing the connection, or if the HttpResponse associated with that LastHttpContent requested closing the connection or didn't have a self defined message length.

Since HttpServerKeepAliveHandler expects HttpObjects it should be added after HttpServerCodec but before any other handlers that might send a HttpResponse.

 ChannelPipeline p = ...;
 ...
 p.addLast("serverCodec", new HttpServerCodec());
 p.addLast("httpKeepAlive", new HttpServerKeepAliveHandler());
 p.addLast("aggregator", new HttpObjectAggregator(1048576));
 ...
 p.addLast("handler", new HttpRequestHandler());

Field Summary

Modifier and Type	Field and Description
private static final String	MULTIPART_PREFIX
private int	pendingResponses
private boolean	persistentConnection

Constructor Summary

Access	Constructor and Description
public	HttpServerKeepAliveHandler()

Method Summary

Modifier and Type	Method and Description
public void	channelRead(ChannelHandlerContext ctx, Object msg) Overrides io.netty.channel.ChannelInboundHandlerAdapter.channelRead. Implements io.netty.channel.ChannelInboundHandler.channelRead. Calls `ChannelHandlerContext#fireChannelRead(Object)` to forward to the next `ChannelInboundHandler` in the `ChannelPipeline`.
private static boolean	isInformational(HttpResponse response)
private static boolean	isMultipart(HttpResponse response)
private static boolean	Returns: true if the response has a self defined message length. isSelfDefinedMessageLength(HttpResponse The HttpResponse to check response) Keep-alive only works if the client can detect when the message has ended without relying on the connection being closed.
private boolean	shouldKeepAlive()
private void	trackResponse(HttpResponse response)
public void	write(ChannelHandlerContext the `ChannelHandlerContext` for which the write operation is made ctx, Object the message to write msg, ChannelPromise the `ChannelPromise` to notify once the operation completes promise) Overrides io.netty.channel.ChannelDuplexHandler.write. Implements io.netty.channel.ChannelOutboundHandler.write. Calls `ChannelHandlerContext#write(Object, ChannelPromise)` to forward to the next `ChannelOutboundHandler` in the `ChannelPipeline`.

Inherited from io.netty.channel.ChannelDuplexHandler:: bind close connect deregister disconnect flush read

Field Detail

MULTIPART_PREFIX	back to summary
private static final String MULTIPART_PREFIX

pendingResponses	back to summary
private int pendingResponses

persistentConnection	back to summary
private boolean persistentConnection

Constructor Detail

HttpServerKeepAliveHandler	back to summary
public HttpServerKeepAliveHandler()

Method Detail

channelRead back to summary

channelRead	back to summary
public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception Overrides io.netty.channel.ChannelInboundHandlerAdapter.channelRead. Implements io.netty.channel.ChannelInboundHandler.channelRead. Doc from io.netty.channel.ChannelInboundHandlerAdapter.channelRead. Calls `ChannelHandlerContext#fireChannelRead(Object)` to forward to the next `ChannelInboundHandler` in the `ChannelPipeline`. Sub-classes may override this method to change behavior. Annotations @Override

public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception

Overrides io.netty.channel.ChannelInboundHandlerAdapter.channelRead.

Implements io.netty.channel.ChannelInboundHandler.channelRead.

Doc from io.netty.channel.ChannelInboundHandlerAdapter.channelRead.

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

Annotations

@Override

isInformational	back to summary
private static boolean isInformational(HttpResponse response)

isMultipart	back to summary
private static boolean isMultipart(HttpResponse response)

isSelfDefinedMessageLength	back to summary
private static boolean isSelfDefinedMessageLength(HttpResponse response) Keep-alive only works if the client can detect when the message has ended without relying on the connection being closed. See See See Parameters response:HttpResponse The HttpResponse to check Returns:boolean true if the response has a self defined message length.

isSelfDefinedMessageLength

back to summary

private static boolean isSelfDefinedMessageLength(HttpResponse response)

Keep-alive only works if the client can detect when the message has ended without relying on the connection being closed.

Parameters

shouldKeepAlive	back to summary
private boolean shouldKeepAlive()

trackResponse	back to summary
private void trackResponse(HttpResponse response)

write back to summary

write	back to summary
public void write(ChannelHandlerContext ctx, Object msg, ChannelPromise promise) throws Exception Overrides io.netty.channel.ChannelDuplexHandler.write. Implements io.netty.channel.ChannelOutboundHandler.write. Doc from io.netty.channel.ChannelDuplexHandler.write. Calls `ChannelHandlerContext#write(Object, ChannelPromise)` to forward to the next `ChannelOutboundHandler` in the `ChannelPipeline`. Sub-classes may override this method to change behavior. Parameters ctx:ChannelHandlerContext Doc from io.netty.channel.ChannelOutboundHandler.write. the `ChannelHandlerContext` for which the write operation is made msg:Object Doc from io.netty.channel.ChannelOutboundHandler.write. the message to write promise:ChannelPromise Doc from io.netty.channel.ChannelOutboundHandler.write. the `ChannelPromise` to notify once the operation completes Annotations @Override Exceptions Exception: Doc from io.netty.channel.ChannelOutboundHandler.write. thrown if an error occurs