NIO案例-聊天室

NIO案例-聊天室

1. 聊天室服务端编写

package com.my.io.chat.server;
​
import java.io.IOException;
import java.net.InetSocketAddress;
import java.nio.ByteBuffer;
import java.nio.channels.*;
import java.nio.charset.StandardCharsets;
import java.util.Iterator;
import java.util.Set;
​
/*** @author zhupanlin* @version 1.0* @description: 聊天室的服务端* @date 2024/1/27 9:55*/
public class ChatServer {
​public static void main(String[] args) {try {// 创建ServerSocketChannelServerSocketChannel serverSocketChannel = ServerSocketChannel.open();// 设置为非阻塞模式serverSocketChannel.configureBlocking(false);// 绑定端口serverSocketChannel.bind(new InetSocketAddress(9001));// 得到selectorSelector selector = Selector.open();// 将channel注册到selector上，并让selector对其接收的就绪状态感兴趣serverSocketChannel.register(selector, SelectionKey.OP_ACCEPT);System.out.println("聊天室服务器启动成功");// 轮询处理while (true){// 获得处于就绪状态的channel的总数int select = selector.select();if (select == 0){continue;}// 获得就绪状态所有的selectionKeys集合Set<SelectionKey> selectionKeys = selector.selectedKeys();// 遍历selectionKeys集合Iterator<SelectionKey> iterator = selectionKeys.iterator();while (iterator.hasNext()) {SelectionKey selectionKey = iterator.next();// 判断channel哪个操作处于就绪状态 channel被封装在selectionKey中if (selectionKey.isAcceptable()){// 说明有客户端连接，处理客户端的连接handleAccept(selectionKey);}else if (selectionKey.isReadable()){// 说明有客户端向服务端写数据，处理客户端的写请求handleRead(selectionKey);}//删除当前keyiterator.remove();}}} catch (IOException e) {throw new RuntimeException(e);}}
​/*** 处理客户端的连接请求* @param selectionKey*/private static void handleAccept(SelectionKey selectionKey) {try {// 得到ServerSocketChannelServerSocketChannel channel = (ServerSocketChannel) selectionKey.channel();// 获得selectorSelector selector = selectionKey.selector();// 建立连接，获得socketChannel 此socketChannel与客户端的socketChannel为同一个SocketChannel socketChannel = channel.accept();// 将socketChannel设置成非阻塞socketChannel.configureBlocking(false);// 注册到selector中，让Selector对它的读操作感兴趣socketChannel.register(selector, SelectionKey.OP_READ);// 服务端向客户端回复一条消息String message = "欢迎进入聊天室";socketChannel.write(ByteBuffer.wrap(message.getBytes(StandardCharsets.UTF_8)));} catch (IOException e) {throw new RuntimeException(e);}
​}
​/*** 处理客户端写数据的请求--服务端处于读操作的就绪状态* 获得客户端写的数据，并且广播给其它所有的客户端* @param selectionKey*/private static void handleRead(SelectionKey selectionKey) {try {// 获得SocketChannelSocketChannel socketChannel = (SocketChannel) selectionKey.channel();// 获得selectorSelector selector = selectionKey.selector();// 创建BufferByteBuffer buffer = ByteBuffer.allocate(1024);// 读取数据到buffer中int len = 0;// 存放客户端发来的消息String message = "";while ((len = socketChannel.read(buffer)) > 0){buffer.flip();// 封装messagemessage += new String(buffer.array(), 0, len, StandardCharsets.UTF_8);}// 把客户端发送的消息，广播给其它所有客户端if (message.length() > 0){// 服务端本地打印System.out.println(socketChannel.getRemoteAddress() + ":" + message);// 广播消息handleMessage(message, selectionKey);}} catch (IOException e) {throw new RuntimeException(e);}}
​/*** 广播消息给其它所有客户端* @param message * @param selectionKey*/private static void handleMessage(String message, SelectionKey selectionKey) {try {// 获得selectorSelector selector = selectionKey.selector();// 获得selector上面所有注册的channelSet<SelectionKey> keys = selector.keys();// 遍历for (SelectionKey key : keys) {SelectableChannel channel = key.channel();// 不发给自己if (channel != selectionKey.channel() && channel instanceof SocketChannel){// 发送消息// 获得SocketChannelSocketChannel socketChannel = (SocketChannel) channel;// 发送消息socketChannel.write(ByteBuffer.wrap(message.getBytes(StandardCharsets.UTF_8)));}}} catch (IOException e) {throw new RuntimeException(e);}}
​
}

2.聊天室客户端编写

package com.my.io.chat.client;
​
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.nio.charset.StandardCharsets;
import java.util.Iterator;
import java.util.Scanner;
import java.util.Set;
​
/*** @author zhupanlin* @version 1.0* @description: 客户端程序*                  1. 发送数据到服务端*                  2. 接收服务端发来的消息* @date 2024/1/27 11:07*/
public class ChatClient {
​/*** 启动客户端的方法* @param name 聊天室昵称*/public void start(String name){try {// 创建channelSocketChannel socketChannel = SocketChannel.open(new InetSocketAddress("localhost", 9001));// 设置成非阻塞socketChannel.configureBlocking(false);// 获得selectorSelector selector = Selector.open();// 注册channel到selector上，让selector对其读操作感兴趣，读取服务端发来的消息socketChannel.register(selector, SelectionKey.OP_READ);// 创建线程 专门负责发送消息new SendMessageThread(socketChannel, name).start();// 循环selectorwhile (true){// 获得这次就绪状态的channel数量int select = selector.select();if (select == 0){continue;}// 获得所有就绪状态的channelSet<SelectionKey> selectionKeys = selector.selectedKeys();Iterator<SelectionKey> iterator = selectionKeys.iterator();// 遍历while (iterator.hasNext()) {SelectionKey key = iterator.next();if (key.isReadable()){// 如果是读操作就绪，说明服务端广播数据了// 获得channelSocketChannel channel = (SocketChannel) key.channel();// 创建bufferByteBuffer buffer = ByteBuffer.allocate(1024);// 读取int len = 0;String message = "";while ((len = channel.read(buffer)) > 0){buffer.flip();// 封装messagemessage += new String(buffer.array(), 0, len, StandardCharsets.UTF_8);buffer.clear();}// 打印消息System.out.println(message);// 将channel再次注册到selector上，并让selector对读感兴趣channel.register(selector, SelectionKey.OP_READ);}// 移除keyiterator.remove();}}} catch (IOException e) {throw new RuntimeException(e);}}}
​
class SendMessageThread extends Thread{// 要发消息的socketChaneelprivate SocketChannel socketChannel;//自己的昵称private String name;
​public SendMessageThread(SocketChannel socketChannel, String name) {this.socketChannel = socketChannel;this.name = name;}
​@Overridepublic void run() {// 控制台输入Scanner sc = new Scanner(System.in);while (sc.hasNextLine()){String message = sc.nextLine();// 带上名字String sendMessage = name + ":" + message;// 发消息到channeltry {if (message.length() > 0){socketChannel.write(ByteBuffer.wrap(sendMessage.getBytes(StandardCharsets.UTF_8)));}} catch (IOException e) {throw new RuntimeException(e);}}}
}