java 通信
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UDP
package com.le; import org.junit.Test; import java.io.IOException; import java.net.DatagramPacket; import java.net.DatagramSocket; import java.net.InetAddress; import java.net.SocketException; /** * <pre> * <b>类描述:</b> java UDP 实现 * <b>作者:</b> zhanglei29 * <b>创建日期:</b> 2019/4/9 16:33 * </pre> */ public class UDP { /** * java -> UDP 发送报文数据 */ @Test public void send() { try { String sendStr = "使用UDP发送数据报文"; DatagramSocket socket = new DatagramSocket(); DatagramPacket packet = new DatagramPacket(sendStr.getBytes(), sendStr.getBytes().length, InetAddress.getByName("127.0.0.1"), 6666); socket.send(packet); socket.close(); } catch (IOException e) { e.printStackTrace(); } } /** * java -> UDP 接收报文 */ @Test public void receive() { try { DatagramSocket socket = new DatagramSocket(6666); DatagramPacket packet = new DatagramPacket(new byte[1024], 1024); socket.receive(packet); byte[] arr = packet.getData(); int len = packet.getLength(); String ip = packet.getAddress().getHostAddress(); System.out.println(ip + ":" + new String(arr, 0, len)); } catch (IOException e) { e.printStackTrace(); } } }
TCP
package com.le; import org.junit.Test; import java.io.*; import java.net.ServerSocket; import java.net.Socket; /** * <pre> * <b>类描述:</b> java TCP 接收和发送报文 * <b>作者:</b> zhanglei29 * <b>创建日期:</b> 2019/4/9 16:52 * </pre> */ public class TCP { /** * java -> TCP 接收报文数据 */ @Test public void client() { try { Socket socket = new Socket("127.0.0.1", 5555); InputStream is = socket.getInputStream(); OutputStream os = socket.getOutputStream(); BufferedReader br = new BufferedReader(new InputStreamReader(is)); PrintStream ps = new PrintStream(os); System.out.println(br.readLine()); ps.println("客户端 回传数据 111111111"); System.out.println(br.readLine()); ps.println("客户端 回传数据 222222222"); socket.close(); } catch (Exception e) { e.printStackTrace(); } } /** * java -> TCP 发送报文数据 */ @Test public void server(){ try { ServerSocket server = new ServerSocket(5555); Socket socket = server.accept(); InputStream is = socket.getInputStream(); OutputStream os = socket.getOutputStream(); BufferedReader br = new BufferedReader(new InputStreamReader(is)); PrintStream ps = new PrintStream(os); ps.println("服务端 发送数据 111111111111"); System.out.println(br.readLine()); ps.println("服务端 发送数据 222222222222"); System.out.println(br.readLine()); server.close(); socket.close(); } catch (Exception e) { e.printStackTrace(); } } }
NIO
Server
package com.le; 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; /** * <pre> * <b>类描述:</b> * <b>作者:</b> zhanglei29 * <b>创建日期:</b> 2019/4/8 17:53 * </pre> */ public class Nioserver { /*标识数字*/ private int flag = 0; /*缓冲区大小*/ private int BLOCK = 4096; /*接受数据缓冲区*/ private ByteBuffer sendbuffer = ByteBuffer.allocate(BLOCK); /*发送数据缓冲区*/ private ByteBuffer receivebuffer = ByteBuffer.allocate(BLOCK); private Selector selector; public NIOServer(int port) throws IOException { // 打开服务器套接字通道 ServerSocketChannel serverSocketChannel = 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 = serverSocketChannel.socket(); // 进行服务的绑定 serverSocket.bind(new InetSocketAddress(port)); // 通过open()方法找到Selector selector = Selector.open(); // 注册到selector，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，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<SelectionKey> selectionKeys = selector.selectedKeys(); Iterator<SelectionKey> iterator = selectionKeys.iterator(); while (iterator.hasNext()) { SelectionKey selectionKey = iterator.next(); iterator.remove(); handleKey(selectionKey); } } } // 处理请求 private void handleKey(SelectionKey selectionKey) throws IOException { // 接受请求 ServerSocketChannel server = null; SocketChannel client = null; String receiveText; String sendText; int count = 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()) { System.out.println("isAcceptable"); // 返回为之创建此键的通道。 server = (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（如果有）将处于阻塞模式。 client = server.accept(); // 配置为非阻塞 client.configureBlocking(false); // 注册到selector，等待连接 client.register(selector, SelectionKey.OP_READ); } else if (selectionKey.isReadable()) { System.out.println("isReadable"); // 返回为之创建此键的通道。 client = (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 = client.read(receivebuffer); if (count > 0) { receiveText = new String(receivebuffer.array(), 0, count); System.out.println("服务器端接受客户端数据--:" + receiveText); client.register(selector, SelectionKey.OP_WRITE); } } else if (selectionKey.isWritable()) { System.out.println("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 = (SocketChannel) selectionKey.channel(); sendText = "message from server--" + flag++; //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--：" + sendText); client.register(selector, SelectionKey.OP_READ); } } /** * @param args * @throws IOException */ public static void main(String[] args) throws IOException { // TODO Auto-generated method stub int port = 8888; NIOServer server = new NIOServer(port); server.listen(); } }
Client
package com.le; 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; /** * <pre> * <b>类描述:</b> * <b>作者:</b> zhanglei29 * <b>创建日期:</b> 2019/4/8 17:57 * </pre> */ public class NIOClient { /*标识数字*/ private static int flag = 0; /*缓冲区大小*/ private static int BLOCK = 4096; /*接受数据缓冲区*/ private static ByteBuffer sendbuffer = ByteBuffer.allocate(BLOCK); /*发送数据缓冲区*/ private static ByteBuffer receivebuffer = ByteBuffer.allocate(BLOCK); /*服务器端地址*/ private final static InetSocketAddress SERVER_ADDRESS = new InetSocketAddress( "localhost", 8888); public static void main(String[] args) throws IOException { // TODO Auto-generated method stub // 打开socket通道 SocketChannel socketChannel = SocketChannel.open(); // 设置为非阻塞方式 socketChannel.configureBlocking(false); // 打开选择器 Selector selector = 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<SelectionKey> selectionKeys; Iterator<SelectionKey> iterator; SelectionKey selectionKey; SocketChannel client; String receiveText; String sendText; int count=0; while (true) { //选择一组键，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 = selector.selectedKeys(); //System.out.println(selectionKeys.size()); iterator = selectionKeys.iterator(); while (iterator.hasNext()) { selectionKey = iterator.next(); if (selectionKey.isConnectable()) { System.out.println("client connect"); client = (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 = (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=client.read(receivebuffer); if(count>0){ receiveText = new String( receivebuffer.array(),0,count); System.out.println("客户端接受服务器端数据--:"+receiveText); client.register(selector, SelectionKey.OP_WRITE); } } else if (selectionKey.isWritable()) { sendbuffer.clear(); client = (SocketChannel) selectionKey.channel(); sendText = "message from client--" + (flag++); 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--："+sendText); client.register(selector, SelectionKey.OP_READ); } } selectionKeys.clear(); } } }
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