need any good example of volatile in synchronization

• Volatile field will be accessed only by one thread at a time (Java will put locks around it).
• Synchronized block or method will be accessed by only one thread at a time for the whole object.

   volatile int b;

synchronized int getA(){

    return a;

}

synchronized int getB(){

    return b;

}

then two threads can access a and b concurrently, but not getA() and getB(). Only one thread can access a synchronized method across the whole object.