223efc5f99
Motivation: The examples have not been updated since long time ago, showing various issues fixed in this commit. Modifications: - Overall simplification to reduce LoC - Use system properties to get options instead of parsing args. - Minimize option validation - Just use System.out/err instead of Logger - Do not pass config as parameters - just access it directly - Move the main logic to main(String[]) instead of creating a new instance meaninglessly - Update netty-build-21 to make checkstyle not complain - Remove 'throws Exception' clause if possible - Line wrap at 120 (previously at 80) - Add an option to enable SSL for most examples - Use ChannelFuture.sync() instead of await() - Use System.out for the actual result. Use System.err otherwise. - Delete examples that are not very useful: - applet - websocket/html5 - websocketx/sslserver - localecho/multithreaded - Add run-example.sh which simplifies launching an example from command line - Rewrite FileServer example Result: Shorter and simpler examples. A user can focus more on what it actually does than miscellaneous stuff. A user can launch an example very easily.
111 lines
3.6 KiB
Java
111 lines
3.6 KiB
Java
/*
|
|
* Copyright 2012 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 io.netty.example.factorial;
|
|
|
|
import io.netty.channel.ChannelFuture;
|
|
import io.netty.channel.ChannelFutureListener;
|
|
import io.netty.channel.ChannelHandlerContext;
|
|
import io.netty.channel.SimpleChannelInboundHandler;
|
|
|
|
import java.math.BigInteger;
|
|
import java.util.concurrent.BlockingQueue;
|
|
import java.util.concurrent.LinkedBlockingQueue;
|
|
|
|
/**
|
|
* Handler for a client-side channel. This handler maintains stateful
|
|
* information which is specific to a certain channel using member variables.
|
|
* Therefore, an instance of this handler can cover only one channel. You have
|
|
* to create a new handler instance whenever you create a new channel and insert
|
|
* this handler to avoid a race condition.
|
|
*/
|
|
public class FactorialClientHandler extends SimpleChannelInboundHandler<BigInteger> {
|
|
|
|
private ChannelHandlerContext ctx;
|
|
private int receivedMessages;
|
|
private int next = 1;
|
|
final BlockingQueue<BigInteger> answer = new LinkedBlockingQueue<BigInteger>();
|
|
|
|
public BigInteger getFactorial() {
|
|
boolean interrupted = false;
|
|
try {
|
|
for (;;) {
|
|
try {
|
|
return answer.take();
|
|
} catch (InterruptedException ignore) {
|
|
interrupted = true;
|
|
}
|
|
}
|
|
} finally {
|
|
if (interrupted) {
|
|
Thread.currentThread().interrupt();
|
|
}
|
|
}
|
|
}
|
|
|
|
@Override
|
|
public void channelActive(ChannelHandlerContext ctx) {
|
|
this.ctx = ctx;
|
|
sendNumbers();
|
|
}
|
|
|
|
@Override
|
|
public void channelRead0(ChannelHandlerContext ctx, final BigInteger msg) {
|
|
receivedMessages ++;
|
|
if (receivedMessages == FactorialClient.COUNT) {
|
|
// Offer the answer after closing the connection.
|
|
ctx.channel().close().addListener(new ChannelFutureListener() {
|
|
@Override
|
|
public void operationComplete(ChannelFuture future) {
|
|
boolean offered = answer.offer(msg);
|
|
assert offered;
|
|
}
|
|
});
|
|
}
|
|
}
|
|
|
|
@Override
|
|
public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) {
|
|
cause.printStackTrace();
|
|
ctx.close();
|
|
}
|
|
|
|
private void sendNumbers() {
|
|
// Do not send more than 4096 numbers.
|
|
ChannelFuture future = null;
|
|
for (int i = 0; i < 4096 && next <= FactorialClient.COUNT; i++) {
|
|
future = ctx.write(Integer.valueOf(next));
|
|
next++;
|
|
}
|
|
if (next <= FactorialClient.COUNT) {
|
|
assert future != null;
|
|
future.addListener(numberSender);
|
|
}
|
|
ctx.flush();
|
|
}
|
|
|
|
private final ChannelFutureListener numberSender = new ChannelFutureListener() {
|
|
@Override
|
|
public void operationComplete(ChannelFuture future) throws Exception {
|
|
if (future.isSuccess()) {
|
|
sendNumbers();
|
|
} else {
|
|
future.cause().printStackTrace();
|
|
future.channel().close();
|
|
}
|
|
}
|
|
};
|
|
}
|