/** * 享元模式:简单点说就是使用了缓存的方式,用map或list来存已经创建的对象,获取的时候直接从map或者list中获取就行了,获取不到再new出来,然后再存进去; * 用到的地方有各种常量池,Short在jdk中-128到127的值是缓存在一个数组中,这里使用一个Map简单模拟下缓存模式 * * */public class ShapeFactory {    private static Map
     
       map=new HashMap<>();    public static Shape getShape(String shapeName){        Shape shape = map.get(shapeName);        if(null==shape){            shape = new Shape();            map.put(shapeName,shape);        }        return shape;    }}public class Shape {    private String name;    public String getName() {        return name;    }    public void setName(String name) {        this.name = name;    }}public class Test {    public static void main(String[] args) {        Shape circle1 = ShapeFactory.getShape("circle");//获取圆形        Shape circle2 = ShapeFactory.getShape("circle");//获取圆形        System.out.println(circle1==circle2);//true    }}