new ServerSocket(int)是开启监听端口，并不是连接端口。真正的连接端口是随机开辟的空闲端口，当连接创建完成后，监听关口可以继续等待下一次连接请求，处于空闲等待状态。
编程实现方式
1
、主线程一直处于阻塞等待状态，如果一旦链接成功则启动一个新线程对外提供服务。
2
、启动工作线程时将链接对象
Socket
传递过去，在
run
方法中执行处理逻辑。
服务器编程实现
public class MyServer {
public static void main(String[] args) throws IOException {
ServerSocket serverSocket = new ServerSocket(9000);
while (true){
Socket scoket = serverSocket.accept();
new WorkThread(scoket).start();
}
}
}
class WorkThread extends Thread{
private Socket scoket;
public WorkThread(Socket scoket){
this.scoket = scoket;
}
@Override
public void run() {
try {
InputStream is = scoket.getInputStream();
OutputStream os = scoket.getOutputStream();
BufferedReader br = new BufferedReader(new InputStreamReader(is));
PrintWriter out = new PrintWriter(os);
String str = br.readLine();
out.println("收到"+str);
out.flush();
out.close();
br.close();
scoket.close();
} catch (IOException e) {
System.out.println(e.getMessage());
}
}
}客户端编程实现
public class MyClient {
public static void main(String[] args) throws IOException {
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
System.out.println("你想给服务器说：");
String str1 = br.readLine();
Socket socket = new Socket("localhost",9001);
System.out.println(socket.getInetAddress());
System.out.println(socket.getPort());
InputStream is = socket.getInputStream();
OutputStream os = socket.getOutputStream();
BufferedReader br2= new BufferedReader(new InputStreamReader(is));
PrintWriter out = new PrintWriter(os);
out.println(str1);
out.flush();
String str2 = br2.readLine();
System.out.println(str2);
br2.close();
out.close();
br.close();
}
}
