Package io.netty.handler.codec.http

Class HttpServerKeepAliveHandler

java.lang.Object

io.netty.channel.ChannelHandlerAdapter

io.netty.channel.ChannelInboundHandlerAdapter

io.netty.channel.ChannelDuplexHandler

io.netty.handler.codec.http.HttpServerKeepAliveHandler

All Implemented Interfaces:

ChannelHandler, ChannelInboundHandler, ChannelOutboundHandler

public class HttpServerKeepAliveHandler
extends ChannelDuplexHandler

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());
  

Nested Class Summary

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

ChannelHandler.Sharable

Field Summary

Fields

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

Constructor Summary

Constructors

Constructor	Description
HttpServerKeepAliveHandler()

Method Summary

Modifier and Type	Method	Description
void	channelRead(ChannelHandlerContext ctx, Object msg)	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	isSelfDefinedMessageLength(HttpResponse 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)
void	write(ChannelHandlerContext ctx, Object msg, ChannelPromise promise)	Calls ChannelOutboundInvoker.write(Object, ChannelPromise) to forward to the next ChannelOutboundHandler in the ChannelPipeline.

Methods inherited from class io.netty.channel.ChannelDuplexHandler

bind, close, connect, deregister, disconnect, flush, read

Methods inherited from class io.netty.channel.ChannelInboundHandlerAdapter

channelActive, channelInactive, channelReadComplete, channelRegistered, channelUnregistered, channelWritabilityChanged, exceptionCaught, userEventTriggered

Methods inherited from class io.netty.channel.ChannelHandlerAdapter

ensureNotSharable, handlerAdded, 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

handlerAdded, handlerRemoved

Field Details

MULTIPART_PREFIX

private static final String MULTIPART_PREFIX

See Also:

• Constant Field Values

persistentConnection

private boolean persistentConnection

pendingResponses

private int pendingResponses

Constructor Details

HttpServerKeepAliveHandler

public HttpServerKeepAliveHandler()

Method Details

channelRead

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

Description copied from class: ChannelInboundHandlerAdapter

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

Specified by:

channelRead in interface ChannelInboundHandler

Overrides:

channelRead in class ChannelInboundHandlerAdapter

Throws:

Exception

write

public void write(ChannelHandlerContext ctx,
 Object msg,
 ChannelPromise promise)
           throws Exception

Description copied from class: ChannelDuplexHandler

Calls ChannelOutboundInvoker.write(Object, ChannelPromise) to forward to the next ChannelOutboundHandler in the ChannelPipeline. Sub-classes may override this method to change behavior.

Specified by:

write in interface ChannelOutboundHandler

Overrides:

write in class ChannelDuplexHandler

Parameters:

ctx - the ChannelHandlerContext for which the write operation is made

msg - the message to write

promise - the ChannelPromise to notify once the operation completes

Throws:

Exception - thrown if an error occurs

trackResponse

private void trackResponse(HttpResponse response)

shouldKeepAlive

private boolean shouldKeepAlive()

isSelfDefinedMessageLength

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 - The HttpResponse to check

Returns:

true if the response has a self defined message length.

isInformational

private static boolean isInformational(HttpResponse response)

isMultipart

private static boolean isMultipart(HttpResponse response)