/*
* Copyright 2011 The Netty Project
*
* The Netty Project licenses this file to you under the Apache License,
* version 2.0 (the "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at:
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*/
package org.jboss.netty.channel;
import java.util.EventListener;
/**
* Listens to the result of a {@link ChannelFuture}. The result of the
* asynchronous {@link Channel} I/O operation is notified once this listener
* is added by calling {@link ChannelFuture#addListener(ChannelFutureListener)}.
*
* <h3>Return the control to the caller quickly</h3>
*
* {@link #operationComplete(ChannelFuture)} is directly called by an I/O
* thread. Therefore, performing a time consuming task or a blocking operation
* in the handler method can cause an unexpected pause during I/O. If you need
* to perform a blocking operation on I/O completion, try to execute the
* operation in a different thread using a thread pool.
*/
public interface ChannelFutureListener extends EventListener {
/**
* A {@link ChannelFutureListener} that closes the {@link Channel} which is
* associated with the specified {@link ChannelFuture}.
*/
ChannelFutureListener CLOSE = new ChannelFutureListener() {
public void operationComplete(ChannelFuture future) {
future.getChannel().close();
}
};
/**
* A {@link ChannelFutureListener} that closes the {@link Channel} when the
* operation ended up with a failure or cancellation rather than a success.
*/
ChannelFutureListener CLOSE_ON_FAILURE = new ChannelFutureListener() {
public void operationComplete(ChannelFuture future) {
if (!future.isSuccess()) {
future.getChannel().close();
}
}
};
/**
* Invoked when the I/O operation associated with the {@link ChannelFuture}
* has been completed.
*
* @param future the source {@link ChannelFuture} which called this
* callback
*/
void operationComplete(ChannelFuture future) throws Exception;
}