Fix Multi thread problem

Question

Hi everyone
I have a main program that tries to run two threads. here is the part of the main
R_Thread rThread1 = new R_Thread(9);
Thread t1 = new Thread(rThread1, "first");
t1.start();
R_Thread rThread2 = new R_Thread(8);
Thread t2 = new Thread(rThread2, "second");
t2.start();and here is my runnable:
public class R_Thread implements Runnable {
     private int ID = -1;
     public R_Thread(int location){
         ID = location;
     public void run() {
          try {
               while (true) {
                   dostuff();
                       Thread.sleep(5000);
          catch(InterruptedException e) {
                   System.out.println(e.toString());
    public void dostuff() {
}as you can see i'm trying to run two threads but with different ID's. my program is supposed to read the data, process it and store it in DB. this works well but sometimes it misses to process the data. like it skips some data and continues with the other. my best guess is two threads are interfering with each other.
i apologize for being vague but i don't know how else can i explain. Please feel free to ask any question, hopefully i can explain better. can anyone recommend me something to fix this?? thanks

Answer 1

hey guys thanks for the input. i am trying to implement something different now.
     public class R_Thread implements Runnable {
          private int ID = -1;
          public R_Thread(int location){
               ID = location;
          public void run() {
               try {
                    while (true) {
                         if(Thread.currentThread().getName().equals("first")){
                              dostuff();
                              Thread.currentThread().wait();
                              //notify to resume thread "second"
                         else if (Thread.currentThread().getName().equals("second")){
                              dostuff();
                              Thread.currentThread().wait();
                              //notify to resume thread "first"                              
               catch(InterruptedException e) {
                    System.out.println(e.toString());
          public void dostuff() {
     }how can i do this?? also i got this IllegalMonitorStateException error, how can make currentthread owner of the monitor?
Edited by: d_khakh on Jun 4, 2009 2:33 PM