Question

is it possible to execute same function concurrently from thread. I have doubt that in java method area is same so the multiple call to same function may lead to waiting state , am i correct?

Answer 1

yes, it is possible unless you have used synchronization there wont be any waiting for lock. This is the default behavior, no locking and thread execution can be interleaved.

Though remember that your thread scheduler will allow one thread to run at a given time.

By default in absence of synchronization concurrent access without wait is the behavior.

Sample to demostrate

public class MyThread implements Runnable {

    private MyThreadInvocation  threadInvocation    = null;

    public MyThread(MyThreadInvocation threadInvocation) {
        this.threadInvocation = threadInvocation;
    }

    @Override
    public void run() {
        System.out.println("Calling from : " + Thread.currentThread().getName());
        this.threadInvocation.printMessage();
    }
}


public class MyThreadInvocation {
    public void printMessage(){
        System.out.println("Hello");
    }

    public static void main(String[] args) {
        MyThreadInvocation myThreadInvocation = new MyThreadInvocation();
        Thread t1 = new Thread(new MyThread(myThreadInvocation));
        t1.setName("First Thread");

        Thread t2 = new Thread(new MyThread(myThreadInvocation));
        t2.setName("Second Thread");

        Thread t3 = new Thread(new MyThread(myThreadInvocation));
        t3.setName("Third Thread");

        t1.start();
        t2.start();
        t3.start();
    }
}