Thread: Multithreading

I have a question regarding join(),setPriority() methods. How we can I see the working of these methods?. I could not get the reality in windows OS when i coded in java. Is it due to Windows is preemtive scheduling and due to this it dint behave appropriately? Ideally when join() is invoked on a thread, the current thread which has applied join() on a thread, current thread waits until the thread on which join is performed gets done but this was not the case when i ran the program.
Example : t3.join(); t1.join(); t2.join(); This has to work as mentioned below.

T3 thread completes its process and then T1 gets done and finally it goes with T2. But what i saw is T1, T2 and T3 got done in sequential manner which should not be.

Any idea why it behaved so?

Can you post a small program that compiles, executes and shows what you are asking about.

Can you post a small, complete program that compiles, executes and shows what you are asking about.

My Question is, The thread which is been set to MAX_PRIORITY has to be executed first and thread which has LOW_PRIORITY has to be executed last but it's not working so.

Code:

package first;
 
class A extends Thread {
	public void run() {
		System.out.println("Thread A");
	}
}
 
class B extends Thread {
	public void run() {
		System.out.println("Thread B");
	}
}
 
class C extends Thread {
	public void run() {
		System.out.println("Thread C");
	}
}
 
public class ThreadPriorityDemo {
	public static void main(String args[]) {
		A threadA = new A();
		B threadB = new B();
		C threadC = new C();
		threadC.setPriority(Thread.MAX_PRIORITY);
		threadB.setPriority(threadA.getPriority() + 1);
		threadA.setPriority(Thread.MIN_PRIORITY);
		threadA.start();
		threadB.start();
		threadC.start();
		System.out.println("End of main thread");
	}
}

OUTPUT:

Thread A
Thread B
End of main thread
Thread C

What do you expect the output should be and why?
The code is trivial and will probably execute immediately when started.

Please edit your post and wrap your code with
[code=java]
<YOUR CODE HERE>
[/code]
to get highlighting and preserve formatting.

ThreadC has got maximum priority which is 10, so it has to be processed at first.

ThreadA is started first and finishes immediately. ThreadC has not been started yet.

You need the threads to do something that takes longer so that their priority can have an effect.

Try adding some calls to yield() or sleep() inside the threads.
The tight loops in the code don't give the OS time to get control and pass control to another thread.