学习Java07

1.访问私有构造函数:创建一个变量 将外来变量初始化的时候传进来class Singleton{private static  Singleton instance=new Singleton();private Singleton(){}public void print(){System.out.println("success");}public static Singleton getInstance(){return instance;}}public class Day {         public static void main(String args[]) { Singleton inst =null; inst = Singleton.getInstance(); inst.print();      }             }得出唯一的一个实列化对象2.多例class Sex{private static final Sex MALE =new Sex("male");private static final Sex FEMALE =new Sex("female");private String title;private Sex(String title){this.title=title;}public static Sex getInstance(String msg){   switch(msg) {case "male" :return MALE ;case "female" :return FEMALE ;default: return null;}}public String getTitle(){return this.title;}}public class Day {         public static void main(String args[]) { Sex male=Sex.getInstance("female"); System.out.println(male.getTitle());      }             }