synch_block2.java

class Display {

    public void wish(String name) {
        // consider here 1 lakh line of code which can be executed by mutliple threads
        // simaltaneously
        ;
        ;
        ;
        ;
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        ;
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        ;
        ;
        // if very few lines of code required synchronization then we should declare
        // that code inside synchronizaion block
        synchronized (this) {

            for (int i = 0; i < 5; i++) {
                System.out.print("good morning:");
                try {
                    Thread.sleep(1000);
                } catch (InterruptedException e) {
                }
                System.out.println(name);
            }

        }
        ;
        ;
        ;
        ;
        ;
        ;
        ;
        ;
        ;
        ;
        ;
        ;
        ;
        ;
        ;
        ;
        ;
        ;
        ;
        ;
        ;
        ;
        ;
        ;
        ;
        ;
        ;
        ;
        ;
        ;
        // consider here 1 lakh line of code which can be executed by mutliple threads
        // simaltaneously
    }

}

class MyThread extends Thread {
    Display d;
    String name;

    MyThread(Display d, String s) {
        this.d = d;
        this.name = s;
    }

    public void run() {
        d.wish(name);
    }
}

public class synch_block2 {
    public static void main(String[] args) {
        Display d1 = new Display();
        Display d2 = new Display();
        // Both threads are executing on different display Objects so we get irregualr o/p 
        MyThread t1 = new MyThread(d1, "dhoni");
        MyThread t2 = new MyThread(d2, "Yuvraj");
        t1.start();
        t2.start();
    }

}