java例程练习（网络编程[简单双向通信试验]）

import java.net.*;
import java.io.*;
public class TestTCPClient {
public static void main(String[] args) {
InputStream in = null;
OutputStream out = null;

try {

Socket socket = new Socket("localhost", 8888);
in = socket.getInputStream();
out = socket.getOutputStream();

DataInputStream dis = new DataInputStream(in);
DataOutputStream dos = new DataOutputStream(out);

dos.writeUTF("Hey");

String s = null;

if((s = dis.readUTF()) != null) {
System.out.println(s);
}

dis.close();
dos.close();
socket.close();

} catch(UnknownHostException e) {
e.printStackTrace();
}catch(IOException e) {
e.printStackTrace();
}

}
}