/*
 * 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.channel.socket.nio;

import io.netty.channel.ChannelException;
import io.netty.channel.ChannelMetadata;
import io.netty.channel.ChannelOutboundBuffer;
import io.netty.util.internal.SocketUtils;
import io.netty.channel.nio.AbstractNioMessageChannel;
import io.netty.channel.socket.DefaultServerSocketChannelConfig;
import io.netty.channel.socket.ServerSocketChannelConfig;
import io.netty.util.internal.PlatformDependent;
import io.netty.util.internal.logging.InternalLogger;
import io.netty.util.internal.logging.InternalLoggerFactory;

import java.io.IOException;
import java.net.InetSocketAddress;
import java.net.ServerSocket;
import java.net.SocketAddress;
import java.nio.channels.SelectionKey;
import java.nio.channels.ServerSocketChannel;
import java.nio.channels.SocketChannel;
import java.nio.channels.spi.SelectorProvider;
import java.util.List;

A ServerSocketChannel implementation which uses NIO selector based implementation to accept new connections.
/** * A {@link io.netty.channel.socket.ServerSocketChannel} implementation which uses * NIO selector based implementation to accept new connections. */
public class NioServerSocketChannel extends AbstractNioMessageChannel implements io.netty.channel.socket.ServerSocketChannel { private static final ChannelMetadata METADATA = new ChannelMetadata(false, 16); private static final SelectorProvider DEFAULT_SELECTOR_PROVIDER = SelectorProvider.provider(); private static final InternalLogger logger = InternalLoggerFactory.getInstance(NioServerSocketChannel.class); private static ServerSocketChannel newSocket(SelectorProvider provider) { try { /** * Use the {@link SelectorProvider} to open {@link SocketChannel} and so remove condition in * {@link SelectorProvider#provider()} which is called by each ServerSocketChannel.open() otherwise. * * See <a href="https://github.com/netty/netty/issues/2308">#2308</a>. */ return provider.openServerSocketChannel(); } catch (IOException e) { throw new ChannelException( "Failed to open a server socket.", e); } } private final ServerSocketChannelConfig config;
Create a new instance
/** * Create a new instance */
public NioServerSocketChannel() { this(newSocket(DEFAULT_SELECTOR_PROVIDER)); }
Create a new instance using the given SelectorProvider.
/** * Create a new instance using the given {@link SelectorProvider}. */
public NioServerSocketChannel(SelectorProvider provider) { this(newSocket(provider)); }
Create a new instance using the given ServerSocketChannel.
/** * Create a new instance using the given {@link ServerSocketChannel}. */
public NioServerSocketChannel(ServerSocketChannel channel) { super(null, channel, SelectionKey.OP_ACCEPT); config = new NioServerSocketChannelConfig(this, javaChannel().socket()); } @Override public InetSocketAddress localAddress() { return (InetSocketAddress) super.localAddress(); } @Override public ChannelMetadata metadata() { return METADATA; } @Override public ServerSocketChannelConfig config() { return config; } @Override public boolean isActive() { return javaChannel().socket().isBound(); } @Override public InetSocketAddress remoteAddress() { return null; } @Override protected ServerSocketChannel javaChannel() { return (ServerSocketChannel) super.javaChannel(); } @Override protected SocketAddress localAddress0() { return SocketUtils.localSocketAddress(javaChannel().socket()); } @Override protected void doBind(SocketAddress localAddress) throws Exception { if (PlatformDependent.javaVersion() >= 7) { javaChannel().bind(localAddress, config.getBacklog()); } else { javaChannel().socket().bind(localAddress, config.getBacklog()); } } @Override protected void doClose() throws Exception { javaChannel().close(); } @Override protected int doReadMessages(List<Object> buf) throws Exception { SocketChannel ch = SocketUtils.accept(javaChannel()); try { if (ch != null) { buf.add(new NioSocketChannel(this, ch)); return 1; } } catch (Throwable t) { logger.warn("Failed to create a new channel from an accepted socket.", t); try { ch.close(); } catch (Throwable t2) { logger.warn("Failed to close a socket.", t2); } } return 0; } // Unnecessary stuff @Override protected boolean doConnect( SocketAddress remoteAddress, SocketAddress localAddress) throws Exception { throw new UnsupportedOperationException(); } @Override protected void doFinishConnect() throws Exception { throw new UnsupportedOperationException(); } @Override protected SocketAddress remoteAddress0() { return null; } @Override protected void doDisconnect() throws Exception { throw new UnsupportedOperationException(); } @Override protected boolean doWriteMessage(Object msg, ChannelOutboundBuffer in) throws Exception { throw new UnsupportedOperationException(); } @Override protected final Object filterOutboundMessage(Object msg) throws Exception { throw new UnsupportedOperationException(); } private final class NioServerSocketChannelConfig extends DefaultServerSocketChannelConfig { private NioServerSocketChannelConfig(NioServerSocketChannel channel, ServerSocket javaSocket) { super(channel, javaSocket); } @Override protected void autoReadCleared() { clearReadPending(); } } // Override just to to be able to call directly via unit tests. @Override protected boolean closeOnReadError(Throwable cause) { return super.closeOnReadError(cause); } }