的Java通信客户端/服务器

Question

这是我的客户：

public static void logIn(String name, String pass) { 
try { 
    Socket s = new Socket("localhost", 9000); 
    PrintStream out = new PrintStream(s.getOutputStream()); 
    BufferedReader in = new BufferedReader(new InputStreamReader(s.getInputStream())); 
    out.print(name + "," + pass); 
    out.flush(); 
    out.close(); 

    System.out.println(in.readLine()); 

    in.close(); 
    s.close(); 
} 
catch(UnknownHostException exp) 
{ 
    exp.printStackTrace(); 

} 
catch(java.io.IOException exp) 
{ 
    exp.printStackTrace(); 
} 
} 

，这我在我的服务器：

public static void main(String[] args){ 
boolean clientExists=false; 
ArrayList<User> users = new ArrayList<User>(); 
users.add(new User("jmeno","heslo")); 
ServerSocket ss; 
try { 
    ss = new ServerSocket(9000); 
    while(true) { 
       clientExists=false; 
     Socket s = ss.accept(); 
     BufferedReader in = new BufferedReader(new InputStreamReader(s.getInputStream())); 
     PrintStream out = new PrintStream(s.getOutputStream()); 
     String xmlpacket=""; 
       String pom; 

       while ((pom = in.readLine())!=null){ 
        xmlpacket+=pom; 
        xmlpacket+="\n"; 
       } 

       for(User us: users) 
        { 
          if(us.isUserNameAndPasswordRight(login, passwd)) 
          { 
            out.print("user is connected"); 
            out.flush(); 
            clientExists=true; 
          } 
        } 
       } 
       if(clientExist != true) 
       out.print("bad login"); 
     out.flush(); 
     out.close(); 
     in.close(); 
     s.close(); 
} 
catch(java.io.IOException exp) 
{ 
    System.out.println("chyba u socketu!"); 
} 

}

它更多钞票，以这样的工作？我不能得到这个工作，因为在客户端尝试从服务器读取答案时出现异常。

编辑： 这是堆栈跟踪：

java.net.SocketException: socket closed 
    at java.net.SocketInputStream.socketRead0(Native Method) 
    at java.net.SocketInputStream.read(Unknown Source) 
    at java.net.SocketInputStream.read(Unknown Source) 
    at sun.nio.cs.StreamDecoder.readBytes(Unknown Source) 
    at sun.nio.cs.StreamDecoder.implRead(Unknown Source) 
    at sun.nio.cs.StreamDecoder.read(Unknown Source) 
    at java.io.InputStreamReader.read(Unknown Source) 
    at java.io.BufferedReader.fill(Unknown Source) 
    at java.io.BufferedReader.readLine(Unknown Source) 
    at java.io.BufferedReader.readLine(Unknown Source) 
    at client.client.logIn(client.java:79) 


    at client.GUI.GUI.jMenuItem1ActionPerformed(GUI.java:379) 
    at client.GUI.GUI.access$5(GUI.java:367) 
    at client.GUI.GUI$5.actionPerformed(GUI.java:151) 
    at javax.swing.AbstractButton.fireActionPerformed(Unknown Source) 
    at javax.swing.AbstractButton$Handler.actionPerformed(Unknown Source) 
    at javax.swing.DefaultButtonModel.fireActionPerformed(Unknown Source) 
    at javax.swing.DefaultButtonModel.setPressed(Unknown Source) 
    at javax.swing.AbstractButton.doClick(Unknown Source) 
    at javax.swing.plaf.basic.BasicMenuItemUI.doClick(Unknown Source) 
    at javax.swing.plaf.basic.BasicMenuItemUI$Handler.mouseReleased(Unknown Source) 
    at java.awt.Component.processMouseEvent(Unknown Source) 
    at javax.swing.JComponent.processMouseEvent(Unknown Source) 
    at java.awt.Component.processEvent(Unknown Source) 
    at java.awt.Container.processEvent(Unknown Source) 
    at java.awt.Component.dispatchEventImpl(Unknown Source) 
    at java.awt.Container.dispatchEventImpl(Unknown Source) 
    at java.awt.Component.dispatchEvent(Unknown Source) 
    at java.awt.LightweightDispatcher.retargetMouseEvent(Unknown Source) 
    at java.awt.LightweightDispatcher.processMouseEvent(Unknown Source) 
    at java.awt.LightweightDispatcher.dispatchEvent(Unknown Source) 
    at java.awt.Container.dispatchEventImpl(Unknown Source) 
    at java.awt.Window.dispatchEventImpl(Unknown Source) 
    at java.awt.Component.dispatchEvent(Unknown Source) 
    at java.awt.EventQueue.dispatchEventImpl(Unknown Source) 
    at java.awt.EventQueue.access$000(Unknown Source) 
    at java.awt.EventQueue$3.run(Unknown Source) 
    at java.awt.EventQueue$3.run(Unknown Source) 
    at java.security.AccessController.doPrivileged(Native Method) 
    at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source) 
    at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source) 
    at java.awt.EventQueue$4.run(Unknown Source) 
    at java.awt.EventQueue$4.run(Unknown Source) 
    at java.security.AccessController.doPrivileged(Native Method) 
    at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source) 
    at java.awt.EventQueue.dispatchEvent(Unknown Source) 
    at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source) 
    at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source) 
    at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source) 
    at java.awt.EventDispatchThread.pumpEvents(Unknown Source) 
    at java.awt.EventDispatchThread.pumpEvents(Unknown Source) 
    at java.awt.EventDispatchThread.run(Unknown Source) 

Answer 1

我做了几件事情，所以给所有的代码。

• 稍后放置缓冲读取器，以防止阻塞。
• 增加了编码，因此它不使用默认的操作系统编码（不同操作系统上的客户端）。
• Did println i.o.打印。
• 自动清理。
• 重要：没有PrintStream，但PrintWriter。

• xmlpacket上没有循环;那是后来的代码。

  public static void logIn(String name, String pass) { 
  try { 
      Socket s = new Socket("localhost", 9000); 
      //PrintStream out = new PrintStream(s.getOutputStream(), true, "UTF-8"); 
      PrintWriter out = new PrintWriter(new OutputStreamWriter(s.getOutputStream(), "UTF-8"), true); 
      out.println(name + "," + pass); 
      out.flush(); 
  
      BufferedReader in = new BufferedReader(new InputStreamReader(
        s.getInputStream(), "UTF-8")); 
  
      System.out.println(in.readLine()); 
  
      out.close(); 
      in.close(); 
      s.close(); 
  } catch (UnknownHostException exp) { 
      exp.printStackTrace(); 
  
  } catch (java.io.IOException exp) { 
      exp.printStackTrace(); 
  } 
  } 
  
  
  public static void main(String[] args) { 
  ArrayList<User> users = new ArrayList<User>(); 
  users.add(new User("jmeno", "heslo")); 
  ServerSocket ss; 
  try { 
      ss = new ServerSocket(9000); 
      while (true) { 
       Socket s = ss.accept(); 
       System.out.println("Accept..."); 
       BufferedReader in = new BufferedReader(new InputStreamReader(
         s.getInputStream(), "UTF-8")); 
       PrintWriter out = new PrintWriter(new OutputStreamWriter(s.getOutputStream(), "UTF-8"), true); 
       String xmlpacket = ""; 
       String pom; 
  
       pom = in.readLine(); 
       //while ((pom = in.readLine()) != null) { 
        xmlpacket += pom; 
        xmlpacket += "\n"; 
       //} 
       int commaPos = xmlpacket.indexOf(','); 
       int newlinePos = xmlpacket.indexOf('\n'); 
       String login = xmlpacket.substring(0, commaPos); 
       String passwd = xmlpacket.substring(commaPos + 1, newlinePos);       
  
       boolean clientExists = false; 
       for (User us : users) { 
        if (us.isUserNameAndPasswordRight(login, passwd)) { 
         out.println("user is connected"); 
         clientExists = true; 
         break; 
        } 
       } 
       if (!clientExists) 
        out.println("bad login"); 
       out.close(); 
       in.close(); 
       s.close(); 
      } 
  } catch (java.io.IOException exp) { 
      System.out.println("chyba u socketu!"); 
  } 
  } 
  

Answer 2

尝试带走了out.close()看看会发生什么。我相信关闭OutputStream也会关闭相关的套接字。在阅读回复之前，你不想这样做。

更新：只是要清楚，我的意思是带走（或移动到末尾）在客户端，而不是服务器的out.close()。

Answer 3

'out.print（name +“，”+ pass）;'似乎不会发出行结束符，因此您的客户端中的'readLine（）'将不会返回。尝试'println'并摆脱封闭的陷阱。