While loop not looping more than once in java

This won't loop more than once, so I am unable to check if I have a client message:

 new Thread() {    
   public void run() {
     while(true) {
       for(int I=0; I<numPlayers; I++) {
         if(!players[I].isConnected()) {
           players[I].drop();
           System.out.println("Client disconnected!");
           players[I]=null;
           readers[I]=null;
           writers[I]=null;
           numPlayers--;
         }
         try {
           System.out.println(readers[I].ready());
           if(readers[I].ready()) {
             BufferedReader reader = readers[I];
             System.out.println("Reading");
             switch(reader.read()) {
              case PacketID.Connect:
                System.out.println("Connect");
                players[I].name=reader.readLine();
                PrintWriter writer=writers[I];
                writer.write(PacketID.Connect);
                writer.write(MaxPlayers);
                writer.write(numPlayers);
                for(int I2=0;I2<numPlayers;I2++){
                  writer.println(players[I2].name);
                  players[I2].sendMessage(
                    "Client "+players[I].name+" has connected!");
                }
                writer.flush();
            开发者_运维百科    break;
              case PacketID.Ready:
                System.out.println("lolol lol");
                break;
            }
          }
        } catch (IOException e) {
          // TODO Auto-generated catch block
          e.printStackTrace();
        }
      }
    }
   }
 }.start();

I can see people saying my code is messy and inefficient. I'm going to clean it all up later Also I don't know why stack overflow is malformatting my code.

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Your logic of looping on

for(int I=0;I<numPlayers;I++)

is flawed because it assumes no "holes" in the players array. What if you have 3 players connected (0,1,2) and player #0 disconnects? You'll decrement "numPlayers" and never look at player #2 again.

Also, you don't appear to be checking for null in your readers and writers array, so you no sooner set readers[I]=null then you start trying to reference it.

   ...
    readers[I]=null;
    writers[I]=null;
    numPlayers--;
   }
    try {
    System.out.println(readers[I].ready());
     ...

Odds are you're throwing a null pointer exception somewhere in all this, and not seeing it because you're running the whole thing in a thread.

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reader.read() might be blocking for input

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Some misplaced break statement might be breaking out of the while loop.

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Your code does look correct as far the while loop goes. Are there any exceptions being thrown. That will be only reason.

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I have not run your example but my thought process is as follows - the thread starts and runs to completion. That is why I asked if you can try to run the code without the thread. That may help you isolate your issue. cheers

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Based on the print out (Hi false ..), I think readers[i].ready() is actually returning false and that is what stopping you from reading. I am not sure who sets the "ready" to be true. No exception, just simple dropping off the loop.. :)

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I fixed it, using isConnected hung the server

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Can you put the try in an else statement?
You probably don't want to read anything from the reader that is null!