How to make two threads in Java?

V

Vadim Gush2014-09-17 16:40:18

Java

Vadim Gush, 2014-09-17 16:40:18

I can't solve the problem with the server. It is necessary that Input and Output be in different streams, but how to separate them into two different streams? I tried, but after running them I got this:

Exception in thread "Thread-1" Exception in thread "Thread-0" java.lang.NullPointerException
  at server.ServerInput.run(ServerInput.java:21)
  at java.lang.Thread.run(Thread.java:745)
java.lang.NullPointerException
  at server.ServerOutput.run(ServerOutput.java:20)
  at java.lang.Thread.run(Thread.java:745)

Here is the code that I need to split into two threads. Help me please:

try {
      server = new ServerSocket(SettingsServer.getPort(), SettingsServer.getMaxUsers());
      while (true) {
        connect = server.accept();
        output = new ObjectOutputStream(connect.getOutputStream());
        input = new ObjectInputStream(connect.getInputStream());
        
        inObject = (String)input.readObject();
        
        if (inObject.equals("<html><table><tr><td>&&&$server_recd;</td></tr></center></html>") == true) {
          SettingsServer.CounterPlus();
        }
        
        if (inObject.equals("<html><table><tr><td>/server</td></tr></center></html>") == true) {
          SettingsServer.CounterPlus();
          sendData(SettingsServer.getInformation());
        }
        
        if (inObject != null && inObject.equals("<html><table><tr><td>&&&$server_recd;</td></tr></center></html>") == false && inObject.equals("<html><table><tr><td>/server</td></tr></center></html>") == false) {
          SettingsServer.CounterPlus();
          last_message.setText(inObject);
          sendData("&&&$client_recd;");
        }
        
        inObject = null;
        
      }
    } catch (UnknownHostException e) {
      e.printStackTrace();
    } catch (IOException e) {
      e.printStackTrace();
    } catch (HeadlessException e) {
      e.printStackTrace();
    } catch (ClassNotFoundException e) {
      e.printStackTrace();
    }

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2 answer(s)

E

Eugene, 2014-09-18
@zolt85

What practical problem do you want to solve?

E

ensiriuswOw, 2014-09-18
@ensiriuswOw

Bad programming style:
Good programming style:
The code looks very doubtful. What are you trying to do? I advise you to look towards Netty if performance is important to you. You can't tell from your code what the problem is.