课程进度 85% · 第9/10章第9/10章 · 标签 1/2
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TCP 通信
Socket 是实现网络通信的基础。Java 提供了 ServerSocket 和 Socket 类简化 TCP 编程。
```java
// 服务器
ServerSocket server = new ServerSocket(8080);
System.out.println("等待客户端连接...");
Socket client = server.accept();
BufferedReader in = new BufferedReader(
new InputStreamReader(client.getInputStream()));
PrintWriter out = new PrintWriter(
client.getOutputStream(), true);
String msg = in.readLine();
System.out.println("收到: " + msg);
out.println("已收到: " + msg);
client.close();
server.close();
// 客户端
Socket socket = new Socket("localhost", 8080);
PrintWriter out = new PrintWriter(
socket.getOutputStream(), true);
BufferedReader in = new BufferedReader(
new InputStreamReader(socket.getInputStream()));
out.println("Hello Server");
System.out.println(in.readLine());
socket.close();
```
java
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// 服务器
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ServerSocket server = new ServerSocket(8080);
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System.out.println("等待客户端连接...");
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Socket client = server.accept();
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BufferedReader in = new BufferedReader(
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new InputStreamReader(client.getInputStream()));
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PrintWriter out = new PrintWriter(
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client.getOutputStream(), true);
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String msg = in.readLine();
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System.out.println("收到: " + msg);
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out.println("已收到: " + msg);
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client.close();
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server.close();
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// 客户端
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Socket socket = new Socket("localhost", 8080);
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PrintWriter out = new PrintWriter(
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socket.getOutputStream(), true);
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BufferedReader in = new BufferedReader(
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new InputStreamReader(socket.getInputStream()));
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out.println("Hello Server");
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System.out.println(in.readLine());
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socket.close();
— 2 —
UDP 通信
```java
// UDP 服务器
DatagramSocket server = new DatagramSocket(9090);
byte[] buf = new byte[1024];
DatagramPacket packet = new DatagramPacket(buf, buf.length);
server.receive(packet);
String msg = new String(packet.getData(), 0, packet.getLength());
System.out.println("收到: " + msg);
InetAddress addr = packet.getAddress();
int port = packet.getPort();
byte[] resp = "ACK".getBytes();
server.send(new DatagramPacket(resp, resp.length, addr, port));
server.close();
// UDP 客户端
DatagramSocket client = new DatagramSocket();
byte[] data = "Hello".getBytes();
client.send(new DatagramPacket(data, data.length,
InetAddress.getByName("localhost"), 9090));
byte[] buf2 = new byte[1024];
DatagramPacket resp2 = new DatagramPacket(buf2, buf2.length);
client.receive(resp2);
System.out.println(new String(resp2.getData(), 0, resp2.getLength()));
client.close();
```
java
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// UDP 服务器
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DatagramSocket server = new DatagramSocket(9090);
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byte[] buf = new byte[1024];
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DatagramPacket packet = new DatagramPacket(buf, buf.length);
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server.receive(packet);
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String msg = new String(packet.getData(), 0, packet.getLength());
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System.out.println("收到: " + msg);
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InetAddress addr = packet.getAddress();
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int port = packet.getPort();
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byte[] resp = "ACK".getBytes();
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server.send(new DatagramPacket(resp, resp.length, addr, port));
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server.close();
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// UDP 客户端
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DatagramSocket client = new DatagramSocket();
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byte[] data = "Hello".getBytes();
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client.send(new DatagramPacket(data, data.length,
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InetAddress.getByName("localhost"), 9090));
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byte[] buf2 = new byte[1024];
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DatagramPacket resp2 = new DatagramPacket(buf2, buf2.length);
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client.receive(resp2);
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System.out.println(new String(resp2.getData(), 0, resp2.getLength()));
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client.close();