饿汉式
public class Singleton {
private static Singleton instance = new Singleton();
private Singleton(){
}
public static Singleton getInstance(){
return instance;
}
}
懒汉式-----可能存在线程安全问题
public class Singleton {
private static Singleton instance = null;
private Singleton(){
}
public static Singleton getInstance(){
if(instance == null ){
instance = new Singleton();
}
return instance;
}
}
