NIO入门实例

服务端

/** Copyright 2015-2101 Shouqi Limousine & chauffeur Group.** Licensed 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.*/
/**
* &＃64;Auther: qianll
* &＃64;Date: 2020年7月8日 下午5:51:14
* &＃64;Description:
*/
package com;import java.io.IOException;
import java.net.InetSocketAddress;
import java.net.ServerSocket;
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.Iterator;
import java.util.Set; public class NIOServer { /*标识数字*/ private int flag &＃61; 0; /*缓冲区大小*/ private int BLOCK &＃61; 4096; /*接受数据缓冲区*/ private ByteBuffer sendbuffer &＃61; ByteBuffer.allocate(BLOCK); /*发送数据缓冲区*/ private ByteBuffer receivebuffer &＃61; ByteBuffer.allocate(BLOCK); private Selector selector; public NIOServer(int port) throws IOException { // 打开服务器套接字通道 ServerSocketChannel serverSocketChannel &＃61; ServerSocketChannel.open(); // 服务器配置为非阻塞 serverSocketChannel.configureBlocking(false); // 检索与此通道关联的服务器套接字 ServerSocket serverSocket &＃61; serverSocketChannel.socket(); // 进行服务的绑定 serverSocket.bind(new InetSocketAddress(port)); // 通过open()方法找到Selector selector &＃61; Selector.open(); // 注册到selector&＃xff0c;等待连接 serverSocketChannel.register(selector, SelectionKey.OP_ACCEPT); System.out.println("Server Start----8888:"); } // 监听 private void listen() throws IOException { while (true) { // 选择一组键&＃xff0c;并且相应的通道已经打开 selector.select(); // 返回此选择器的已选择键集。 Set selectionKeys &＃61; selector.selectedKeys(); Iterator iterator &＃61; selectionKeys.iterator(); while (iterator.hasNext()) { SelectionKey selectionKey &＃61; iterator.next(); iterator.remove(); handleKey(selectionKey); } } } // 处理请求 private void handleKey(SelectionKey selectionKey) throws IOException { // 接受请求 ServerSocketChannel server &＃61; null; SocketChannel client &＃61; null; String receiveText; String sendText; int count&＃61;0; // 测试此键的通道是否已准备好接受新的套接字连接。 if (selectionKey.isAcceptable()) { // 返回为之创建此键的通道。 server &＃61; (ServerSocketChannel) selectionKey.channel(); // 接受到此通道套接字的连接。 // 此方法返回的套接字通道&＃xff08;如果有&＃xff09;将处于阻塞模式。 client &＃61; server.accept(); // 配置为非阻塞 client.configureBlocking(false); // 注册到selector&＃xff0c;等待连接 client.register(selector, SelectionKey.OP_READ); } else if (selectionKey.isReadable()) { // 返回为之创建此键的通道。 client &＃61; (SocketChannel) selectionKey.channel(); //将缓冲区清空以备下次读取 receivebuffer.clear(); //读取服务器发送来的数据到缓冲区中 count &＃61; client.read(receivebuffer); if (count > 0) { receiveText &＃61; new String( receivebuffer.array(),0,count); System.out.println("服务器端接受客户端数据--:"&＃43;receiveText); client.register(selector, SelectionKey.OP_WRITE); } } else if (selectionKey.isWritable()) { //将缓冲区清空以备下次写入 sendbuffer.clear(); // 返回为之创建此键的通道。 client &＃61; (SocketChannel) selectionKey.channel(); sendText&＃61;"message from server--" &＃43; flag&＃43;&＃43;; //向缓冲区中输入数据 sendbuffer.put(sendText.getBytes()); //将缓冲区各标志复位,因为向里面put了数据标志被改变要想从中读取数据发向服务器,就要复位 sendbuffer.flip(); //输出到通道 client.write(sendbuffer); System.out.println("服务器端向客户端发送数据--&＃xff1a;"&＃43;sendText); client.register(selector, SelectionKey.OP_READ); } } /** * &＃64;param args * &＃64;throws IOException */ public static void main(String[] args) throws IOException { // TODO Auto-generated method stub int port &＃61; 8888; NIOServer server &＃61; new NIOServer(port); server.listen(); }
}


客户端

/** Copyright 2015-2101 Shouqi Limousine & chauffeur Group.** Licensed 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.*/
/**
* &＃64;Auther: qianll
* &＃64;Date: 2020年7月8日 下午5:50:24
* &＃64;Description:
*/
package com;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; public class NIOClient { /*标识数字*/ private static int flag &＃61; 0; /*缓冲区大小*/ private static int BLOCK &＃61; 4096; /*接受数据缓冲区*/ private static ByteBuffer sendbuffer &＃61; ByteBuffer.allocate(BLOCK); /*发送数据缓冲区*/ private static ByteBuffer receivebuffer &＃61; ByteBuffer.allocate(BLOCK); /*服务器端地址*/ private final static InetSocketAddress SERVER_ADDRESS &＃61; new InetSocketAddress( "localhost", 8888); public static void main(String[] args) throws IOException { // TODO Auto-generated method stub // 打开socket通道 SocketChannel socketChannel &＃61; SocketChannel.open(); // 设置为非阻塞方式 socketChannel.configureBlocking(false); // 打开选择器 Selector selector &＃61; Selector.open(); // 注册连接服务端socket动作 socketChannel.register(selector, SelectionKey.OP_CONNECT); // 连接 socketChannel.connect(SERVER_ADDRESS); // 分配缓冲区大小内存 Set selectionKeys; Iterator iterator; SelectionKey selectionKey; SocketChannel client; String receiveText; String sendText; int count&＃61;0; while (true) { //选择一组键&＃xff0c;其相应的通道已为 I/O 操作准备就绪。 //此方法执行处于阻塞模式的选择操作。 selector.select(); //返回此选择器的已选择键集。 selectionKeys &＃61; selector.selectedKeys(); //System.out.println(selectionKeys.size()); iterator &＃61; selectionKeys.iterator(); while (iterator.hasNext()) { selectionKey &＃61; iterator.next(); if (selectionKey.isConnectable()) { System.out.println("client connect"); client &＃61; (SocketChannel) selectionKey.channel(); // 判断此通道上是否正在进行连接操作。 // 完成套接字通道的连接过程。 if (client.isConnectionPending()) { client.finishConnect(); System.out.println("完成连接!"); sendbuffer.clear(); sendbuffer.put("Hello,Server".getBytes()); sendbuffer.flip(); client.write(sendbuffer); } client.register(selector, SelectionKey.OP_READ); } else if (selectionKey.isReadable()) { client &＃61; (SocketChannel) selectionKey.channel(); //将缓冲区清空以备下次读取 receivebuffer.clear(); //读取服务器发送来的数据到缓冲区中 count&＃61;client.read(receivebuffer); if(count>0){ receiveText &＃61; new String( receivebuffer.array(),0,count); System.out.println("客户端接受服务器端数据--:"&＃43;receiveText); //注册写事件同时触发写事件client.register(selector, SelectionKey.OP_WRITE); } } else if (selectionKey.isWritable()) { sendbuffer.clear(); client &＃61; (SocketChannel) selectionKey.channel(); sendText &＃61; "message from client--" &＃43; (flag&＃43;&＃43;); sendbuffer.put(sendText.getBytes()); //将缓冲区各标志复位,因为向里面put了数据标志被改变要想从中读取数据发向服务器,就要复位 sendbuffer.flip(); client.write(sendbuffer); System.out.println("客户端向服务器端发送数据--&＃xff1a;"&＃43;sendText); client.register(selector, SelectionKey.OP_READ); } } selectionKeys.clear(); } }
}