1.
public class MySingleton {
private MySingleton() {}
private MySingleton instance = new MySingleton();
public void getInstance() {
return instance;
}
}
2.
public class MySingleton {
private MySingleton() {}
private MySingleton instance = null;
public synchronized void getInstance() {
if (instance == null) {
instance = new MySingleton();
}
return instance;
}
}
3.
public enum MySingleton {
INSTANCE;
}
