10.30第10次作业

匿名对象、单例模式饿汉式、自动生成对象args[]数组使用、静态关键字

package practice;

 
class Person {
        private String name;
        private static int count;
        public Person(){
            count++;
            this.name="NONAME - " + count;
        }
        public Person(String name){
            this.name=name;
        }
        public String getInfo(){
            return "姓名:"+this.name;
        }
    }
    public class DemoOutput {
        public static void main(String args[]) {
            System.out.println(newPerson().getInfo());
            System.out.println(newPerson("A").getInfo());
            System.out.println(newPerson("B").getInfo());
            System.out.println(newPerson().getInfo());
         
    }
};
package practice;
 
class Person1{
    private String name;
    private static int count;
    public Person1(){
        count++;
        System.out.println("产生了"+count+"个实例化对象。");
    }
    public String getInfo(){
        return "姓名:"+this.name;
    }
};
 
public class DemoOutputA {
    public static void main(String args[]){
        new Person1();
        new Person1();
        new Person1();
        new Person1();
        new Person1();
    }
};
package practice;
 
class Person2{
    private String name;
    private int age;
    static String city="A城";
    public Person2(String name,int age){
        this.name=name;
        this.age=age;
    }
    public String getInfo(){
        return"姓名:"+this.name+",年龄:"+this.age+",城市:"+city;
    }
};
 
public class DemoOutputB {
    public static void main(String args[]){
        Person2 per1=new Person2("张三",30);
        Person2 per2=new Person2("李四",31);
        Person2 per3=new Person2("王五",30);
        System.out.println("==========信息修改之前==========");
        System.out.println(per1.getInfo());
        System.out.println(per2.getInfo());
        System.out.println(per3.getInfo());
        System.out.println("==========信息修改之前==========");
        Person2.city="B城";
        System.out.println(per1.getInfo());
        System.out.println(per2.getInfo());
        System.out.println(per3.getInfo());
    }
 
};
 
package practice;
 
class Single{
    private static Single instance=newSingle();
    private Single(){//将构造方法私有化
    }
    public static Single getInstance(){
        return instance;
    }
    public void print(){
        System.out.println("hello world!!!");
    }
};
 
public class DemoOutputC {
    public static void main(String args[]){
        Single s=null;
        s=Single.getInstance();
        s.print();
    }
 
}

posted on 2017-11-06 13:57  kally1004  阅读(89)  评论(0编辑  收藏  举报

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