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标题: 学到网络编程，有问题，求解释 ? [打印本页]

作者: 创出一片辉煌 时间: 2012-7-27 09:47
标题: 学到网络编程，有问题，求解释 ?
Server端：import java.net.*;
import java.io.*;
public class DOSServer {

private static Socket s = null;
private static ServerSocket ss = null;

public static void main (String[] args) throws Exception {

ss = new ServerSocket (8880);
s = ss.accept(); //阻塞式的方法，此方法在连接传入之前一直阻塞
ClientThread ct = new ClientThread(s);
new Thread(ct).start();
System.out.println ("客户端已经连接！");
}
}
class ClientThread implements Runnable {

private Socket s;
private DataInputStream dis;

public ClientThread (Socket s) throws Exception {
this.s = s;
dis = new DataInputStream(s.getInputStream());
}

public void run() {
while (true) {

try {
String str1;
str1 = dis.readUTF();
System.out.println(str1);
} catch (IOException e) {
e.printStackTrace();
}

//DataOutputStream dos = new DataOutputStream(s.getOutputStream());
//BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
//String str2 = "Server: " + br.readLine();
//dos.writeUTF(str2);
}
}

}

Client端：
import java.net.*;
import java.io.*;
public class DOSClient {
public static void main (String[] args) throws Exception {

Socket s = new Socket("127.0.0.1", 8880);

while (true) {

BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
String str1 = "Client: " + br.readLine();

DataOutputStream dos = new DataOutputStream(s.getOutputStream());
dos.writeUTF(str1);

//DataInputStream dis = new DataInputStream(s.getInputStream());
//String str2 = dis.readUTF();
//System.out.println(str2);
}
}
}

提问：为什么Server端只能连接一个Client端

作者: 胡文凡 时间: 2012-7-27 10:37
找到错误了，因为你少加了一个循环控制
import java.net.*;
import java.io.*;
class DOSServer {

private static Socket s = null;
private static ServerSocket ss = null;

public static void main (String[] args) throws Exception {

ss = new ServerSocket (8880);
while(true){ //就是这里了，要加个死循环
s = ss.accept(); //阻塞式的方法，此方法在连接传入之前一直阻塞
ClientThread ct = new ClientThread(s);
new Thread(ct).start();
System.out.println ("客户端已经连接！");
}
}
}
class ClientThread implements Runnable {

private Socket s;
private DataInputStream dis;

public ClientThread (Socket s) throws Exception {
this.s = s;
dis = new DataInputStream(s.getInputStream());
}

public void run() {
while (true) {

try {
String str1;
str1 = dis.readUTF();
System.out.println(str1);
} catch (IOException e) {
e.printStackTrace();
}

//DataOutputStream dos = new DataOutputStream(s.getOutputStream());
//BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
//String str2 = "Server: " + br.readLine();
//dos.writeUTF(str2);
}
}

}

class DOSClient {
public static void main (String[] args) throws Exception {

Socket s = new Socket("127.0.0.1", 8880);

while (true) {

BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
String str1 = "Client: " + br.readLine();

DataOutputStream dos = new DataOutputStream(s.getOutputStream());
dos.writeUTF(str1);

//DataInputStream dis = new DataInputStream(s.getInputStream());
//String str2 = dis.readUTF();
//System.out.println(str2);
}
}
}
可以连多个客户端，但是原来的程序其实还有一些其他问题
运行结果

socket.png (29.78 KB, 下载次数: 21)

作者: 王志明 时间: 2012-7-27 12:27
我讲楼主的代码改了改，我这边运行通过了，也可以连接多个客户端了

服务端：

import java.io.DataInputStream;

import java.io.IOException;

import java.net.ServerSocket;

import java.net.Socket;

public class DOSServer {

private static Socket s = null;

private static ServerSocket ss = null;

public static void main(String[] args) throws Exception {

ss = new ServerSocket(8880);

// 这里要有死循环，这样就可以链接多个客户端

while (true) {

s = ss.accept(); // 阻塞式的方法，此方法在连接传入之前一直阻塞

// 每链接一个客户端就开启一个新的线程为期服务

new Thread(new ClientThread(s)).start();

System.out.println("客户端已经连接！");

}

class ClientThread implements Runnable {

private Socket s;

private DataInputStream dis;

public ClientThread(Socket s) throws Exception {

this.s = s;

dis = new DataInputStream(s.getInputStream());

}

public void run() {

// 循环接受来自客户端的数据

while (true) {

try {

String data = dis.readUTF();

System.out.println("客户端数据：" + data);

} catch (IOException e) {

System.out.println("客户端已经断开连接！");

try {

s.close();

dis.close();

} catch (IOException e1) {

e1.printStackTrace();

}

return;// 如果客户端断开了链接，要结束这个线程

}

客户端：

import java.net.*;

import java.io.*;

class DOSClient {

public static void main(String[] args) throws Exception {

Socket s = new Socket("127.0.0.1", 8880);

BufferedReader br = new BufferedReader(new InputStreamReader(System.in));

DataOutputStream dos = new DataOutputStream(s.getOutputStream());

String data = "";

//循环想服务端输出数据

while (true) {

System.out.println("请输入：");

data = br.readLine();

//如果输入exit，结束当前客户端

if (data.equals("exit")) {

s.shutdownOutput();

br.close();

dos.close();

return;

}

dos.writeUTF(data);

}

作者: 李菁 时间: 2012-7-27 12:27
public static void main (String[] args) throws Exception {

ss = new ServerSocket (8880);
s = ss.accept(); //阻塞式的方法，此方法在连接传入之前一直阻塞
ClientThread ct = new ClientThread(s);
new Thread(ct).start();
System.out.println ("客户端已经连接！");
}
}
class ClientThread implements Runnable {

private Socket s;
private DataInputStream dis;

public ClientThread (Socket s) throws Exception {
this.s = s;
dis = new DataInputStream(s.getInputStream());
}

public void run() {
while (true) {

try {
String str1;
str1 = dis.readUTF();
System.out.println(str1);
} catch (IOException e) {
e.printStackTrace();
}

//DataOutputStream dos = new DataOutputStream(s.getOutputStream());
//BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
//String str2 = "Server: " + br.readLine();    reanLine()是阻塞是方法，没有读到数据，一直等待。
                                                因为在while循环里，所以不会再执行了，也就不会接受另外一个client了
//dos.writeUTF(str2);
}
}

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