volatile and synchronization in Java

MutableInteger

package com.ado.java;

/**
 * Not Thread Safe
 */
public class MutableInteger {

    private int value;

    public int getValue() {
        return value;
    }

    public void setValue(int value) {
        this.value = value;
    }
}

/**
 * Thread Safe
 */
class SynchronizedInteger {

    private int value;

    public synchronized int getValue() {
        return value;
    }

    public synchronized void setValue(int value) {
        this.value = value;
    }
}

class Volatile {

    private static volatile boolean asleep;

    private static void countSleep() {
        // Stuff
    }

    public static void main(String[] args) {
        while (!asleep) {
            countSleep();
        }
    }
}