本例只做簡單功能演示，代碼并不嚴謹，只是說明客戶端如何實現連接服務端簡單代碼。
代碼在集成Eclipse工具下測試編譯運行環(huán)境如下圖所示：
客戶端echoClient.java代碼：
package com.zhengzz.echo;import java.io.BufferedReader;import java.io.IOException;import java.io.InputStreamReader;import java.io.PrintWriter;import java.net.Socket;import java.net.UnknownHostException;class EchoC{ private Socket socket; public EchoC() { // TODO Auto-generated constructor stub try { socket = new Socket("localhost", 60000); } catch (UnknownHostException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } } public void Client() { try { BufferedReader br = new BufferedReader(new InputStreamReader(socket.getInputStream())); PrintWriter pw = new PrintWriter(socket.getOutputStream(), true); BufferedReader lbr = new BufferedReader(new InputStreamReader(System.in)); String linestr = null; while ((linestr = lbr.readLine()) != null) { pw.println(linestr); System.out.println(br.readLine()); if (linestr.equals("bye#")) { break; } } } catch (IOException e) { e.printStackTrace(); } }}public class echoClient { public static void main(String[] args) { new EchoC().Client(); }}服務端echoServer.java代碼：
package com.zhengzz.echo;import java.io.BufferedReader;import java.io.IOException;import java.io.InputStreamReader;import java.io.PrintWriter;import java.net.ServerSocket;import java.net.Socket;class EchoS{ private ServerSocket serverSocket; public EchoS() { try { serverSocket = new ServerSocket(60000); } catch (IOException e) { e.printStackTrace(); } } public void Server() { while (true) { try { Socket socket = serverSocket.accept(); System.out.println("client:" + socket.getInetAddress() + ":" + socket.getLocalPort()); BufferedReader br = new BufferedReader(new InputStreamReader(socket.getInputStream())); PrintWriter pw = new PrintWriter(socket.getOutputStream(), true); String linestr; while ((linestr = br.readLine()) != null) { System.out.println(linestr); pw.println("--->" + linestr); } } catch (IOException e) { System.out.println("連接斷開：（"); } }}}public class echoServer { public static void main(String[] args) { new EchoS().Server(); }}我在Eclipse工具下直接調試結果如下：
下面我們再來看一個 HelloWord 級別的 Java Socket 通信的例子。通訊過程：
先啟動 Server 端，進入一個死循環(huán)以便一直監(jiān)聽某端口是否有連接請求。然后運行 Client 端，客戶端發(fā)出連接請求，服務端監(jiān)聽到這次請求后向客戶端發(fā)回接受消息，連接建立，啟動一個線程去處理這次請求，然后繼續(xù)死循環(huán)監(jiān)聽其他請求?？蛻舳溯斎胱址蟀椿剀囨I，向服務器發(fā)送數據。服務器讀取數據后回復客戶端數據。這次請求處理完畢，啟動的線程消亡。如果客戶端接收到 "OK" 之外的返回數據，會再次發(fā)送連接請求并發(fā)送數據，服務器會為這次連接再次啟動一個線程來進行響應。。。直到當客戶端接收到的返回數據為 "OK" 時，客戶端退出。
服務端源代碼：
package com.defonds.socket.begin; import java.io.BufferedReader; import java.io.DataInputStream; import java.io.DataOutputStream; import java.io.InputStreamReader; import java.net.ServerSocket; import java.net.Socket; public class Server { public static final int PORT = 12345;//監(jiān)聽的端口號 public static void main(String[] args) { System.out.println("服務器啟動.../n"); Server server = new Server(); server.init(); } public void init() { try { ServerSocket serverSocket = new ServerSocket(PORT); while (true) { // 一旦有堵塞, 則表示服務器與客戶端獲得了連接 Socket client = serverSocket.accept(); // 處理這次連接 new HandlerThread(client); } } catch (Exception e) { System.out.println("服務器異常: " + e.getMessage()); } } private class HandlerThread implements Runnable { private Socket socket; public HandlerThread(Socket client) { socket = client; new Thread(this).start(); } public void run() { try { // 讀取客戶端數據 DataInputStream input = new DataInputStream(socket.getInputStream()); String clientInputStr = input.readUTF();//這里要注意和客戶端輸出流的寫方法對應,否則會拋 EOFException // 處理客戶端數據 System.out.println("客戶端發(fā)過來的內容:" + clientInputStr); // 向客戶端回復信息 DataOutputStream out = new DataOutputStream(socket.getOutputStream()); System.out.print("請輸入:/t"); // 發(fā)送鍵盤輸入的一行 String s = new BufferedReader(new InputStreamReader(System.in)).readLine(); out.writeUTF(s); out.close(); input.close(); } catch (Exception e) { System.out.println("服務器 run 異常: " + e.getMessage()); } finally { if (socket != null) { try { socket.close(); } catch (Exception e) { socket = null; System.out.println("服務端 finally 異常:" + e.getMessage()); } } } } } } 客戶端源代碼：
package com.defonds.socket.begin; import java.io.BufferedReader; import java.io.DataInputStream; import java.io.DataOutputStream; import java.io.IOException; import java.io.InputStreamReader; import java.net.Socket; public class Client { public static final String IP_ADDR = "localhost";//服務器地址 public static final int PORT = 12345;//服務器端口號 public static void main(String[] args) { System.out.println("客戶端啟動..."); System.out.println("當接收到服務器端字符為 /"OK/" 的時候, 客戶端將終止/n"); while (true) { Socket socket = null; try { //創(chuàng)建一個流套接字并將其連接到指定主機上的指定端口號 socket = new Socket(IP_ADDR, PORT); //讀取服務器端數據 DataInputStream input = new DataInputStream(socket.getInputStream()); //向服務器端發(fā)送數據 DataOutputStream out = new DataOutputStream(socket.getOutputStream()); System.out.print("請輸入: /t"); String str = new BufferedReader(new InputStreamReader(System.in)).readLine(); out.writeUTF(str); String ret = input.readUTF(); System.out.println("服務器端返回過來的是: " + ret); // 如接收到 "OK" 則斷開連接 if ("OK".equals(ret)) { System.out.println("客戶端將關閉連接"); Thread.sleep(500); break; } out.close(); input.close(); } catch (Exception e) { System.out.println("客戶端異常:" + e.getMessage()); } finally { if (socket != null) { try { socket.close(); } catch (IOException e) { socket = null; System.out.println("客戶端 finally 異常:" + e.getMessage()); } } } } } } 注意： Socket 輸出流寫數據方法是 writeUTF 時，輸入流讀取相關數據要用 readUTF。否則會拋 EOFException 異常。
新聞熱點
疑難解答
