public class UrgSingleton {
private static UrgSingleton uniqueInstance = new UrgSingleton();
private UrgSingleton() {}
public static UrgSingleton getInstance() {
return uniqueInstance;
}
}
public class DoubleSynSingleton {
private static volatile DouleSynSingleton uniqueInstance;
private DoubleSynSingleton() {}
public static DoubleSynSingleton getInstance() {
if (uniqueInstance == null) {
synchronized(DoubleSynSingleton.class) {
if(uniqueInstance == null)
uniqueInstance = new DoubleSynSingleton();
}
}
return uniqueInstance;
}
}