Java tutorial
/* * Copyright 2012 The Netty Project * Copyright 2013 Red Hat, Inc. * * 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.fusesource.hawtdispatch.netty; import io.netty.channel.*; import org.fusesource.hawtdispatch.Dispatch; import org.fusesource.hawtdispatch.DispatchSource; import java.net.ConnectException; import java.net.InetSocketAddress; import java.net.SocketAddress; import java.nio.channels.SelectableChannel; import java.nio.channels.SocketChannel; import java.util.concurrent.ScheduledFuture; import java.util.concurrent.TimeUnit; /** * Abstract base class for {@link Channel} implementations that use * HawtDispatch. * * @author <a href="mailto:nmaurer@redhat.com">Norman Maurer</a> */ abstract class HawtAbstractChannel extends AbstractChannel { protected volatile SelectableChannel ch; /** * The future of the current connection attempt. If not null, subsequent * connection attempts will fail. */ private ChannelPromise connectPromise; private ScheduledFuture<?> connectTimeoutFuture; private ConnectException connectTimeoutException; /** * Creates a new instance. * * @param id * the unique non-negative integer ID of this channel. * Specify {@code null} to auto-generate a unique negative integer * ID. * @param parent * the parent of this channel. {@code null} if there's no parent. * @param ch * the {@link SocketChannel} which will handle the IO or {@code null} if not created yet. */ protected HawtAbstractChannel(Channel parent, Integer id, SelectableChannel ch) { super(parent, id); this.ch = ch; } @Override public InetSocketAddress localAddress() { return (InetSocketAddress) super.localAddress(); } @Override public InetSocketAddress remoteAddress() { return (InetSocketAddress) super.remoteAddress(); } /** * Return the underlying {@link SocketChannel}. Be aware this should only be called after it was set as * otherwise it will throw an {@link IllegalStateException}. */ protected SelectableChannel javaChannel() { if (ch == null) { throw new IllegalStateException("Try to access Channel before eventLoop was registered"); } return ch; } @Override public boolean isOpen() { if (ch == null) { return true; } return ch.isOpen(); } @Override protected boolean isCompatible(EventLoop loop) { return loop instanceof HawtEventLoop; } @Override protected AbstractUnsafe newUnsafe() { return new HawtAbstractUnsafe(); } protected final DispatchSource createSource(int op) { return Dispatch.createSource(javaChannel(), op, ((HawtEventLoop) eventLoop()).queue()); } /** * Connect to the remote peer using the given localAddress if one is specified or {@code null} otherwise. */ protected abstract boolean doConnect(SocketAddress remoteAddress, SocketAddress localAddress) throws Exception; /** * Finish the connect */ protected abstract void doFinishConnect() throws Exception; @Override protected void doClose() throws Exception { if (connectTimeoutFuture != null) { connectTimeoutFuture.cancel(false); } } final class HawtAbstractUnsafe extends AbstractUnsafe { @Override public void connect(final SocketAddress remoteAddress, final SocketAddress localAddress, final ChannelPromise promise) { if (eventLoop().inEventLoop()) { if (!ensureOpen(promise)) { return; } try { if (connectPromise != null) { throw new IllegalStateException("connection attempt already made"); } boolean wasActive = isActive(); if (doConnect(remoteAddress, localAddress)) { promise.setSuccess(); if (!wasActive && isActive()) { pipeline().fireChannelActive(); } } else { connectPromise = promise; // Schedule connect timeout. int connectTimeoutMillis = config().getConnectTimeoutMillis(); if (connectTimeoutMillis > 0) { connectTimeoutFuture = eventLoop().schedule(new Runnable() { @Override public void run() { if (connectTimeoutException == null) { connectTimeoutException = new ConnectException("connection timed out"); } ChannelPromise connectPromise = HawtAbstractChannel.this.connectPromise; if (connectPromise != null && connectPromise.tryFailure(connectTimeoutException)) { close(voidFuture()); } } }, connectTimeoutMillis, TimeUnit.MILLISECONDS); } } } catch (Throwable t) { promise.setFailure(t); closeIfClosed(); } } else { eventLoop().execute(new Runnable() { @Override public void run() { connect(remoteAddress, localAddress, promise); } }); } } /** * Finish connect operation */ public void finishConnect() { assert eventLoop().inEventLoop(); assert connectPromise != null; try { boolean wasActive = isActive(); doFinishConnect(); connectPromise.setSuccess(); if (!wasActive && isActive()) { pipeline().fireChannelActive(); } } catch (Throwable t) { connectPromise.tryFailure(t); closeIfClosed(); } finally { connectTimeoutFuture.cancel(false); connectPromise = null; } } } }