Java io nio netty三种方式实现简单聊天功能 博客分类： java基础 ionionetty聊天
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2024-03-18 22:46:40
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netty和nio的比较：
http://news.cnblogs.com/n/205413/
一：首先是Java IO:
Server:
package com.tch.test.chat.io;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.atomic.AtomicInteger;
public class Server {
private static AtomicInteger counter = new AtomicInteger(0);
private static Map<Integer, PrintWriter> clients = new ConcurrentHashMap<>();
private static ExecutorService pool = Executors.newCachedThreadPool();
public static void main(String[] args) throws Throwable {
ServerSocket serverSocket = new ServerSocket(8888);
try {
while(true){
Socket socket = serverSocket.accept();
System.out.println("a client connected ...");
pool.execute(new ClientSocketHandler(socket));
}
} finally{
serverSocket.close();
}
}
private static class ClientSocketHandler implements Runnable{
private Socket socket;
private Integer id;
public ClientSocketHandler(Socket socket){
this.socket = socket;
id = counter.incrementAndGet();
}
@Override
public void run() {
try {
BufferedReader in = new BufferedReader(new InputStreamReader(socket.getInputStream()));
PrintWriter out = new PrintWriter(socket.getOutputStream());
clients.put(id, out);
System.out.println("client num:" + clients.size());
String msg = null;
while((msg = in.readLine()) != null){
System.out.println("receive msg '" + msg + "' from client-" + id);
sendBack2Client("cllient-" + id + " said : " + msg);
out.flush();
}
} catch (IOException e) {
e.printStackTrace();
}
}
}
private static void sendBack2Client(String msg){
for(PrintWriter client : clients.values()){
client.println(msg);
client.flush();
}
}
}
Client:
package com.tch.test.chat.io;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.Socket;
public class Client {
public static void main(String[] args) throws Throwable {
Socket socket = new Socket("localhost", 8888);
try {
BufferedReader in = new BufferedReader(new InputStreamReader(socket.getInputStream()));
PrintWriter out = new PrintWriter(socket.getOutputStream());
new Thread(new ServerResponseHandler(in)).start();
BufferedReader userInput = new BufferedReader(new InputStreamReader(System.in));
String msg = null;
while((msg = userInput.readLine()) != null){
out.println(msg);
out.flush();
}
} finally{
socket.close();
}
}
private static class ServerResponseHandler implements Runnable{
BufferedReader in;
public ServerResponseHandler(BufferedReader in){
this.in = in;
}
@Override
public void run() {
try {
String msg = null;
while((msg = in.readLine()) != null){
System.out.println(msg);
}
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
二：使用Java NIO:
Server:
package com.tch.test.chat.nio;
import java.io.IOException;
import java.net.InetSocketAddress;
import java.nio.ByteBuffer;
import java.nio.channels.SelectionKey;
import java.nio.channels.Selector;
import java.nio.channels.ServerSocketChannel;
import java.nio.channels.SocketChannel;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.Set;
public class NioServer {
private Set<SelectionKey> selectionKeys = null;
private Iterator<SelectionKey> iterator = null;
private Iterator<SocketChannel> iterator2 = null;
private List<SocketChannel> clients = new ArrayList<SocketChannel>();
private static Selector selector;
static{
try {
selector = Selector.open();
} catch (IOException e) {
e.printStackTrace();
}
}
public static void main(String[] args) throws Exception {
new NioServer().start();
}
private void start() throws Exception{
initSeverSocketChannel();
while(true){
int ready = selector.select();
if(ready > 0){
selectionKeys = selector.selectedKeys();
iterator = selectionKeys.iterator();
while(iterator.hasNext()){
SelectionKey selectionKey = iterator.next();
if(selectionKey.isAcceptable()){
acceptClient(selectionKey);
}else if(selectionKey.isReadable()){
readMsg(selectionKey);
}
iterator.remove();
}
}
}
}
private void initSeverSocketChannel() throws Exception{
ServerSocketChannel serverSocketChannel = ServerSocketChannel.open();
serverSocketChannel.bind(new InetSocketAddress(7878));
serverSocketChannel.configureBlocking(false);
serverSocketChannel.register(selector, SelectionKey.OP_ACCEPT);
}
private void acceptClient(SelectionKey selectionKey) throws Exception{
ServerSocketChannel serverSocketChannel = (ServerSocketChannel)selectionKey.channel();
SocketChannel socketChannel = serverSocketChannel.accept();
socketChannel.configureBlocking(false);
socketChannel.register(selector, SelectionKey.OP_READ);
clients.add(socketChannel);
System.out.println("a client connected ...");
}
private void readMsg(SelectionKey selectionKey) throws Exception{
ByteBuffer buffer = ByteBuffer.allocate(1024);
SocketChannel socketChannel = (SocketChannel)selectionKey.channel();
buffer.clear();
socketChannel.read(buffer);
buffer.flip();
iterator2 = clients.iterator();
SocketChannel socketChannel2 = null;
while(iterator2.hasNext()){
socketChannel2 = iterator2.next();
while(buffer.hasRemaining()){
socketChannel2.write(buffer);
}
buffer.rewind();
}
}
}
Client:
package com.tch.test.chat.nio;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.IOException;
import java.net.InetSocketAddress;
import java.nio.ByteBuffer;
import java.nio.channels.SelectionKey;
import java.nio.channels.Selector;
import java.nio.channels.SocketChannel;
import java.util.Iterator;
import java.util.Set;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JTextArea;
import javax.swing.JTextField;
public class NioClient extends JFrame{
private static final long serialVersionUID = 1L;
private JTextArea area = new JTextArea();
private JTextField textField = new JTextField();
private JButton button = new JButton("Send Message");
private static Selector selector;
static{
try {
selector = Selector.open();
} catch (IOException e) {
e.printStackTrace();
}
}
public static void main(String[] args) throws Exception {
NioClient client = new NioClient();
client.start();
}
private void start() throws Exception{
initFrame();
initSocketChannel();
while(true){
int ready = selector.select();
if(ready > 0){
Set<SelectionKey> selectionKeys = selector.selectedKeys();
Iterator<SelectionKey> iterator = selectionKeys.iterator();
while(iterator.hasNext()){
SelectionKey selectionKey = iterator.next();
if(selectionKey.isReadable()){
readMsg(selectionKey);
}
iterator.remove();
}
}
}
}
private void readMsg(SelectionKey selectionKey) throws Exception{
ByteBuffer buffer = ByteBuffer.allocate(1024);
SocketChannel socketChannel = (SocketChannel)selectionKey.channel();
socketChannel.read(buffer);
buffer.flip();
area.setText(area.getText().trim()+"\n"+new String(buffer.array(),0,buffer.limit(),"utf-8"));
buffer.clear();
}
private void initFrame(){
setBounds(200, 200, 300, 400);
setLayout(new GridLayout(3, 1));
add(area);
add(textField);
add(button);
setDefaultCloseOperation(EXIT_ON_CLOSE);
setVisible(true);
}
private void initSocketChannel() throws Exception{
SocketChannel socketChannel = SocketChannel.open(new InetSocketAddress("localhost", 7878));
socketChannel.configureBlocking(false);
socketChannel.register(selector, SelectionKey.OP_READ);
button.addActionListener(new MyActionListener(socketChannel));
}
private class MyActionListener implements ActionListener{
private SocketChannel socketChannel;
public MyActionListener(SocketChannel socketChannel){
this.socketChannel = socketChannel;
}
@Override
public void actionPerformed(ActionEvent event) {
try {
ByteBuffer buffer = ByteBuffer.allocate(1024);
String message = textField.getText();
if(message == null || message.trim().isEmpty()){
System.out.println("empty message");
return;
}
textField.setText("");
buffer.put(message.getBytes("utf-8"));
buffer.flip();
while(buffer.hasRemaining()){
socketChannel.write(buffer);
}
buffer.clear();
} catch (Exception e) {
e.printStackTrace();
}
}
}
}
三：最后是使用netty(参考jar包里面example里面的例子):
pom.xml添加依赖：
<dependency> <groupId>io.netty</groupId> <artifactId>netty-all</artifactId> <version>4.0.36.Final</version> </dependency>
Server:
/*
* 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 com.tch.test.chat.netty;
import io.netty.bootstrap.ServerBootstrap;
import io.netty.channel.EventLoopGroup;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.nio.NioServerSocketChannel;
import io.netty.example.telnet.TelnetServer;
import io.netty.handler.logging.LogLevel;
import io.netty.handler.logging.LoggingHandler;
/**
* Simple SSL chat server modified from {@link TelnetServer}.
*/
public final class NettyServer {
private static final int PORT = 8992;
public static void main(String[] args) throws Exception {
EventLoopGroup bossGroup = new NioEventLoopGroup(1);
EventLoopGroup workerGroup = new NioEventLoopGroup();
try {
ServerBootstrap b = new ServerBootstrap();
b.group(bossGroup, workerGroup)
.channel(NioServerSocketChannel.class)
.handler(new LoggingHandler(LogLevel.INFO))
.childHandler(new MyServerChannelInitializer());
b.bind(PORT).sync().channel().closeFuture().sync();
} finally {
bossGroup.shutdownGracefully();
workerGroup.shutdownGracefully();
}
}
}
/*
* 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 com.tch.test.chat.netty;
import io.netty.channel.ChannelInitializer;
import io.netty.channel.ChannelPipeline;
import io.netty.channel.socket.SocketChannel;
import io.netty.handler.codec.DelimiterBasedFrameDecoder;
import io.netty.handler.codec.Delimiters;
import io.netty.handler.codec.string.StringDecoder;
import io.netty.handler.codec.string.StringEncoder;
/**
* Creates a newly configured {@link ChannelPipeline} for a new channel.
*/
public class MyServerChannelInitializer extends ChannelInitializer<SocketChannel> {
@Override
public void initChannel(SocketChannel ch) throws Exception {
ChannelPipeline pipeline = ch.pipeline();
// On top of the SSL handler, add the text line codec.
pipeline.addLast(new DelimiterBasedFrameDecoder(8192, Delimiters.lineDelimiter()));
pipeline.addLast(new StringDecoder());
pipeline.addLast(new StringEncoder());
// and then business logic.
pipeline.addLast(new MyServerHandler());
}
}
/*
* 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 com.tch.test.chat.netty;
import io.netty.channel.Channel;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.SimpleChannelInboundHandler;
import java.net.UnknownHostException;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.atomic.AtomicInteger;
/**
* Handles a server-side channel.
*/
public class MyServerHandler extends SimpleChannelInboundHandler<String> {
private static AtomicInteger counter = new AtomicInteger(0);
private static Map<Channel, Integer> channels = new ConcurrentHashMap<Channel, Integer>();
@Override
public void channelActive(final ChannelHandlerContext ctx) throws UnknownHostException {
Integer channelNum = counter.incrementAndGet();
channels.put(ctx.channel(), channelNum);
ctx.writeAndFlush("Hello user-" + channelNum + "\r\n");
}
@Override
public void channelRead0(ChannelHandlerContext ctx, String msg) throws Exception {
// Send the received message to all channels but the current one.
for (Map.Entry<Channel, Integer> entry : channels.entrySet()) {
Channel c = entry.getKey();
if (c != ctx.channel()) {
c.writeAndFlush("user-" + channels.get(ctx.channel()) + " said: " + msg + '\n');
} else {
c.writeAndFlush("[you] said: " + msg + '\n');
}
}
// Close the connection if the client has sent 'bye'.
if ("bye".equals(msg.toLowerCase())) {
ctx.close();
}
}
@Override
public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) {
cause.printStackTrace();
ctx.close();
}
}
Client:
/*
* 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 com.tch.test.chat.netty;
import io.netty.bootstrap.Bootstrap;
import io.netty.channel.Channel;
import io.netty.channel.ChannelFuture;
import io.netty.channel.EventLoopGroup;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.nio.NioSocketChannel;
import io.netty.example.telnet.TelnetClient;
import java.io.BufferedReader;
import java.io.InputStreamReader;
/**
* Simple SSL chat client modified from {@link TelnetClient}.
*/
public final class NettyClient {
private static final String HOST = "127.0.0.1";
private static final int PORT = 8992;
public static void main(String[] args) throws Exception {
EventLoopGroup group = new NioEventLoopGroup();
try {
Bootstrap b = new Bootstrap();
b.group(group)
.channel(NioSocketChannel.class)
.handler(new MyClientChannelInitializer());
// Start the connection attempt.
Channel ch = b.connect(HOST, PORT).sync().channel();
// Read commands from the stdin.
ChannelFuture lastWriteFuture = null;
BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
for (;;) {
String line = in.readLine();
if (line == null) {
break;
}
// Sends the received line to the server.
lastWriteFuture = ch.writeAndFlush(line + "\r\n");
// If user typed the 'bye' command, wait until the server closes
// the connection.
if ("bye".equals(line.toLowerCase())) {
ch.closeFuture().sync();
break;
}
}
// Wait until all messages are flushed before closing the channel.
if (lastWriteFuture != null) {
lastWriteFuture.sync();
}
} finally {
// The connection is closed automatically on shutdown.
group.shutdownGracefully();
}
}
}
/*
* 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 com.tch.test.chat.netty;
import io.netty.channel.ChannelInitializer;
import io.netty.channel.ChannelPipeline;
import io.netty.channel.socket.SocketChannel;
import io.netty.handler.codec.DelimiterBasedFrameDecoder;
import io.netty.handler.codec.Delimiters;
import io.netty.handler.codec.string.StringDecoder;
import io.netty.handler.codec.string.StringEncoder;
/**
* Creates a newly configured {@link ChannelPipeline} for a new channel.
*/
public class MyClientChannelInitializer extends ChannelInitializer<SocketChannel> {
@Override
public void initChannel(SocketChannel ch) throws Exception {
ChannelPipeline pipeline = ch.pipeline();
// On top of the SSL handler, add the text line codec.
pipeline.addLast(new DelimiterBasedFrameDecoder(8192, Delimiters.lineDelimiter()));
pipeline.addLast(new StringDecoder());
pipeline.addLast(new StringEncoder());
// and then business logic.
pipeline.addLast(new MyClientHandler());
}
}
/*
* 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 com.tch.test.chat.netty;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.SimpleChannelInboundHandler;
/**
* Handles a client-side channel.
*/
public class MyClientHandler extends SimpleChannelInboundHandler<String> {
@Override
public void channelRead0(ChannelHandlerContext ctx, String msg) throws Exception {
System.out.println(msg);
}
@Override
public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) {
cause.printStackTrace();
ctx.close();
}
}
OK,以上就是不同的方式实现聊天。
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