Why is synchronized block better than synchronized method?

Question

I have started learning synchronization in threading.

Synchronized method:

public class Counter {

   private static int count = 0;

   public stati         


        

Answer 1

One classic difference between Synchronized block and Synchronized method is that Synchronized method locks the entire object. Synchronized block just locks the code within the block.

Synchronized method: Basically these 2 sync methods disable multithreading. So one thread completes the method1() and the another thread waits for the Thread1 completion.

class SyncExerciseWithSyncMethod {

public synchronized void method1() {
    try {
        System.out.println("In Method 1");
        Thread.sleep(5000);
    } catch (Exception e) {
        System.out.println("Catch of method 1");
    } finally {
        System.out.println("Finally of method 1");
    }

}

public synchronized void method2() {
    try {
        for (int i = 1; i < 10; i++) {
            System.out.println("Method 2 " + i);
            Thread.sleep(1000);
        }
    } catch (Exception e) {
        System.out.println("Catch of method 2");
    } finally {
        System.out.println("Finally of method 2");
    }
}

}

Output

In Method 1

Finally of method 1

Method 2 1

Method 2 2

Method 2 3

Method 2 4

Method 2 5

Method 2 6

Method 2 7

Method 2 8

Method 2 9

Finally of method 2

---

Synchronized block: Enables multiple threads to access the same object at same time [Enables multi-threading].

class SyncExerciseWithSyncBlock {

public Object lock1 = new Object();
public Object lock2 = new Object();

public void method1() {
    synchronized (lock1) {
        try {
            System.out.println("In Method 1");
            Thread.sleep(5000);
        } catch (Exception e) {
            System.out.println("Catch of method 1");
        } finally {
            System.out.println("Finally of method 1");
        }
    }

}

public void method2() {

    synchronized (lock2) {
        try {
            for (int i = 1; i < 10; i++) {
                System.out.println("Method 2 " + i);
                Thread.sleep(1000);
            }
        } catch (Exception e) {
            System.out.println("Catch of method 2");
        } finally {
            System.out.println("Finally of method 2");
        }
    }
}

}

Output

In Method 1

Method 2 1

Method 2 2

Method 2 3

Method 2 4

Method 2 5

Finally of method 1

Method 2 6

Method 2 7

Method 2 8

Method 2 9

Finally of method 2