//第八次作业（包括匿名对象、单例模式饿汉式、自动生成对象args[]数组使用、静态关键字）
//1、
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(new Person().getInfo());
System.out.println(new Person("A").getInfo());
System.out.println(new Person("B").getInfo());
System.out.println(new Person().getInfo());
}
};
//2、
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();
}
};
//3、
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());
}
};
//4、
package practice;
class Single{
private static Single instance=new Single();
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();
}
}
