多个客户端同时访问服务器
我有一个login屏幕，现在说我们有2个用户的用户名：amit和ajay和他们的密码：“通过”和“单词”。现在我想，假设他们是两个桌面应用程序打开在同一system.I要多客户端同时访问服务器。
意思说，在一个login屏幕阿米特进入用户名，然后他的线程应该睡觉，并在第二个login屏幕让阿贾伊input他的用户名，然后阿米特将再次input他的密码后，阿贾伊input他的密码。如何在java中做？请帮助。
在这里，我分享你一个很好的客户端服务器authentication应用程序有一个服务器与多个客户端使用TCP协议进行通信根据您的要求。
回答：
在这里，每个客户端连接在一个独立于服务器的线程中，该线程包含有关客户端的所有信息。 它将解决您的并发问题。
请参阅内嵌评论以获取更多说明。
注意：在端口号1234运行该程序之前，replaceLiveChatClient.java文件中的主机名
运行程序的步骤：
- 首先只运行
LiveChatServer一次 - 然后为多个客户端运行
LiveChatClient尽可能多您想要添加
这里是另外一个样本在同一个上下文中。 请使用Multiclient通信查看Java Server。
Opcode.java：
用于设置客户端 – 服务器通信协议的操作代码
/**************** an interface to define different operation code **************/ public interface Opcode { int CLIENT_USERNAME = 1; int CLIENT_INVALID_USERNAME = 2; int CLIENT_PASSWORD = 3; int CLIENT_INVALID_PASSWORD = 4; int CLIENT_CONNECTED = 5; }
LiveChatServer.java：
单个服务器控制多个客户端
/************************ Live Chat Server *******************/ import java.io.IOException; import java.net.InetAddress; import java.net.ServerSocket; import java.net.Socket; import java.util.HashMap; import java.util.LinkedHashMap; public class LiveChatServer { // Connection state info private static LinkedHashMap<String, ClientThread> clientInfo = new LinkedHashMap<String, ClientThread>(); // TCP Components private ServerSocket serverSocket; // Main Constructor public LiveChatServer() { startServer();// start the server } public void startServer() { String port = "1234"; try { // in constractor we are passing port no, back log and bind address whick will be local // host // port no - the specified port, or 0 to use any free port. // backlog - the maximum length of the queue. use default if it is equal or less than 0 // bindAddr - the local InetAddress the server will bind to int portNo = Integer.valueOf(port); serverSocket = new ServerSocket(portNo, 0, InetAddress.getLocalHost()); System.out.println(serverSocket); System.out.println(serverSocket.getInetAddress().getHostName() + ":" + serverSocket.getLocalPort()); while (true) { Socket socket = serverSocket.accept(); new ClientThread(socket); } } catch (IOException e) { System.out.println("IO Exception:" + e); System.exit(1); } catch (NumberFormatException e) { System.out.println("Number Format Exception:" + e); System.exit(1); } } public static HashMap<String, ClientThread> getClientInfo() { return clientInfo; } // *********************************** Main Method ******************** public static void main(String args[]) { new LiveChatServer(); } }
LiveChatClient.java：
多个客户端连接到单个服务器
/************************ Live Chat Client *******************/ import java.io.BufferedReader; import java.io.IOException; import java.io.InputStreamReader; import java.io.PrintWriter; import java.net.InetAddress; import java.net.Socket; import java.net.SocketException; public class LiveChatClient { private String chatName; private String password; private String serverAddress; // TCP Components private Socket socket; private BufferedReader in; private PrintWriter out; public LiveChatClient() { initHostName(); runClient();// have fun } public void initHostName() { try { serverAddress = "<your system name>"; if (serverAddress == null) System.exit(1); serverAddress = serverAddress.trim(); if (serverAddress.length() == 0)// empty field { System.out.println("Server IP Address or Name can't be blank."); initHostName(); return; } System.out.println("Trying to connect with server...\nServer IP Address:" + serverAddress); // create socket InetAddress inetAddress = InetAddress.getByName(serverAddress); if (!inetAddress.isReachable(60000))// 60 sec { System.out .println("Error! Unable to connect with server.\nServer IP Address may be wrong."); System.exit(1); } initPortNo(); } catch (SocketException e) { System.out.println("Socket Exception:\n" + e); initHostName(); return; } catch (IOException e) { initHostName(); return; } } public void initPortNo() { try { String portNo = "1234"; portNo = portNo.trim(); if (portNo.length() == 0)// empty field { System.out.println("Server port No can't be blank."); initPortNo(); return; } System.out.println("Trying to connect with server...\nServer Port No:" + portNo); socket = new Socket(serverAddress, 1234); in = new BufferedReader(new InputStreamReader(socket.getInputStream())); out = new PrintWriter(socket.getOutputStream(), true); } catch (IOException e) { System.out.println("IO Exception:\n" + e); initPortNo(); return; } } public void sendChatName() throws IOException { System.out.println("Enter user name:"); BufferedReader br = new BufferedReader(new InputStreamReader(System.in)); String name = br.readLine(); if (name == null) System.exit(1); // title case (get only first 9 chars of chat name) chatName = name.trim(); if (name.length() == 0) { System.out.println("Please enter user name."); sendChatName(); return; } // sending opcode first then sending chatName to the server out.println(Opcode.CLIENT_USERNAME); out.println(chatName); } public void sendPassword() throws IOException { System.out.println("Enter password:"); BufferedReader br = new BufferedReader(new InputStreamReader(System.in)); String name = br.readLine(); if (name == null) System.exit(1); // title case (get only first 9 chars of password) password = name.trim(); if (name.length() == 0) { System.out.println("Please enter password."); sendPassword(); return; } // sending opcode first then sending password to the server out.println(Opcode.CLIENT_PASSWORD); out.println(password); } public void runClient() { try { sendChatName(); while (true) { int opcode = Integer.parseInt(in.readLine()); switch (opcode) { case Opcode.CLIENT_INVALID_USERNAME: // this client is connecting System.out.println(chatName + " is invalid user name. Try different one."); sendChatName(); break; case Opcode.CLIENT_PASSWORD: sendPassword(); break; case Opcode.CLIENT_INVALID_PASSWORD: // this client is connecting System.out.println(password + " is invalid password. Try different one."); sendPassword(); break; case Opcode.CLIENT_CONNECTED: System.out.println(chatName + " is connected successfully."); break; } } } catch (IOException e) { System.out.println("Client is closed..."); } } // *********************************** Main Method ******************** public static void main(String args[]) { new LiveChatClient(); } }
ClientThread.java：
服务器为每个客户端启动多个线程，并包含有关所有连接的客户端的信息
/************************ Client Thread *******************/ import java.io.BufferedReader; import java.io.IOException; import java.io.InputStreamReader; import java.io.PrintWriter; import java.net.Socket; import java.util.HashMap; import java.util.Map; public class ClientThread implements Runnable { // TCP Components private Socket socket; private BufferedReader in; private PrintWriter out; private String chatName; private String password; // seperate thread private Thread thread; // boolean variable to check that client is running or not private volatile boolean isRunning = true; // opcode private int opcode; private static Map<String, String> userpass = new HashMap<String, String>(); static { userpass.put("amit", "pass"); userpass.put("ajay", "word"); } public ClientThread(Socket socket) { try { this.socket = socket; in = new BufferedReader(new InputStreamReader(socket.getInputStream())); out = new PrintWriter(socket.getOutputStream(), true); thread = new Thread(this); thread.start(); } catch (IOException e) { System.out.println(e); } } public void run() { try { while (isRunning) { if (!in.ready()) continue; opcode = Integer.parseInt(in.readLine());// getting opcode first from client switch (opcode) { case Opcode.CLIENT_USERNAME: chatName = in.readLine(); System.out.println(chatName + " is reqesting to connect."); boolean result1 = userpass.containsKey(chatName); if (result1) { System.out.println(chatName + " is a valid username."); out.println(Opcode.CLIENT_PASSWORD); } else { System.out.println(chatName + " is a invalid username."); out.println(Opcode.CLIENT_INVALID_USERNAME); } break; case Opcode.CLIENT_PASSWORD: password = in.readLine(); System.out.println(chatName + " is reqesting to connect having password " + password); boolean result2 = userpass.get(chatName).equals(password); if (result2) { System.out.println(password + " is a valid password for username " + chatName); out.println(Opcode.CLIENT_CONNECTED); } else { System.out.println(password + " is a invalid password for username " + chatName); out.println(Opcode.CLIENT_INVALID_PASSWORD); } break; } } // close all connections out.close(); in.close(); socket.close(); } catch (IOException e) { System.out.println(e); } } }
这是两个客户端添加时的输出 。
服务器：
ServerSocket[addr=computerName/14.98.241.102,port=0,localport=1234] computerName:1234 abc is reqesting to connect. abc is a invalid username. ajay is reqesting to connect. ajay is a valid username. ajay is reqesting to connect having password word word is a valid password for username ajay amit is reqesting to connect. amit is a valid username. amit is reqesting to connect having password word word is a invalid password for username amit amit is reqesting to connect having password pass pass is a valid password for username amit
客户端1：（阿杰）
Trying to connect with server... Server IP Address:computerName Trying to connect with server... Server Port No:1234 Enter user name: abc abc is invalid user name. Try different one. Enter user name: ajay Enter password: word ajay is connected successfully.
客户端2：（阿米特）
Trying to connect with server... Server IP Address:computerName Trying to connect with server... Server Port No:1234 Enter user name: amit Enter password: word word is invalid password. Try different one. Enter password: pass amit is connected successfully.
使用此程序作为您的应用程序的初始启动器。 请让我知道，如果你想在程序中添加新的function。
也许你应该考虑研究JavaEE，你所说的主要是做服务器的工作。 每个客户端连接到服务器进行login。 现在如果你需要在javaSE中做100％的桌面，你需要线程，每个线程将连接到本地login。
JavaEE： http ://www.roseindia.net/quickguide/tomcat/Logout.shtml
主题： http : //www.vogella.com/tutorials/JavaConcurrency/article.html
我希望它可以帮助！
