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javamultithreadingfor-loopintegerfinal

Passing non-final integer in another class

I have this problem: I want to execute multiple threads at once, using a for-loop. I want to pass the variable "i" to a method in the thread. But there is an error occuring, I cannot pass a non-final variable "i" into another class. How can I fix that? This is my code:

for (int i = 0; i < 4; i++) { // 4 THREADS AT ONCE
  thread[i] = new Thread() {
    public void run() {
      randomMethod(i); // ERROR HERE
    }
  };
  thread[i].start();
}
Solution

  • Try this 

    for (int i = 0; i < 4; i++) { // 4 THREADS AT ONCE
  final int temp=i;
  thread[i] = new Thread() {
    public void run() {
      randomMethod(temp); // ERROR HERE
    }
  };
  thread[i].start();
}