簡單服務器與客戶端傳輸信息 Test.java ~~~ package chat.a1; import java.net.*; import java.io.*; public class Test { //構造函數 public Test(){ try { //new一個端口 ServerSocket ss=new ServerSocket(9999); System.out.println("服務器正在監聽.."); Socket s=ss.accept(); //System.out.println("我不會顯示");//當沒有客戶端的消息傳輸過來時，這句話是不會輸出的 InputStreamReader isr=new InputStreamReader(s.getInputStream()); BufferedReader br = new BufferedReader(isr); String xinxi = br.readLine(); System.out.println(xinxi); PrintWriter pw =new PrintWriter(s.getOutputStream(),true); pw.println("我是服務器"); } catch (Exception e) { // TODO: handle exception } } public static void main(String[] args) { Test t=new Test(); } } ~~~ Test1.java ~~~ package chat.a1; import java.net.*; import java.io.*; public class Test1 { public static void main(String[] args) { Test1 t=new Test1(); } public Test1(){ try { Socket s=new Socket("127.0.0.1",9999); PrintWriter pw =new PrintWriter(s.getOutputStream(),true); pw.println("我是客戶端"); InputStreamReader isr=new InputStreamReader(s.getInputStream()); BufferedReader br = new BufferedReader(isr); String fanhui = br.readLine(); System.out.println(fanhui); } catch (Exception e) { // TODO: handle exception } } } ~~~ 先啟動服務器Test.java，再啟動客戶端Test1.java 服務器控制臺：  客戶端控制臺：