example_3（实例化同名对象）

实例化同名对象时赋值

public class User {
    int id;
    String name;
    String pwd;
    public User(){}

    public User(int id ,String name){
        super();
        this.id=id;
        this.name=name;
    }

    public User(int id,String name,String pwd){
        this.id=id;
        this.name=name;
        this.pwd=pwd;
    }

    public static void main(String[] args){
        User u1=new User();
        User u2=new User(10,"ojb");
        User u3=new User(100,"100号","123456");
    }
}