package com.niu.demo.reflect;

import java.lang.reflect.Constructor;
import java.lang.reflect.InvocationTargetException;
public class Reflect{
	
	public static void main(String[] args){
		
		Person p = Person.getPerson();
		
		//getClass对象所在的类
		Class cp = p.getClass();
		//getName获取类名
		String className = cp.getName();
		System.out.println(className);
		
		//基础类型也有对应的Class
		Class t1 = double.class;
		Class t2 = int[].class;
		System.out.println("基础类型的Class: "+t1.getName()+"  "+t2.getName());
		
		try{
			
			//第一种
			Class cp_A = Class.forName(className);
			Person p_A = new Person("Zhang",20);
			
			//第二种
			Class cp_B = p_A.getClass();
			
			//第三种
			Class cp_C = Person.class;
			
			//不管通过某种方式获取类的Class实例，都将是同一个 
			//ture
			System.out.println("同一个类的多个实例返回的Class相同："+(cp==cp_A&&cp_A==cp_B&&cp_B==cp_C));
			
			//使用Class的newInstance创建此类的新实例
			//newInstance将调用默认构造，所以私有的构造函数将导致错误
			Object p_B = cp_C.newInstance();
			
			//使用getDeclaredConstructors返回构造器集合并选择使用创建新实例
			Constructor[] cons = cp_C.getDeclaredConstructors();
			for(Constructor t : cons){
				System.out.println(t);
			}
			
			//私有构造 必须设置权限
			cons[0].setAccessible(true);
			Person p_C = (Person)cons[0].newInstance(true);
			p_C.getDescription();
			
			//公共构造则不需要
			p_C = (Person)cons[1].newInstance("Li",30);
			p_C.getDescription();
			
			p_C = (Person)cons[2].newInstance();
			p_C.getDescription();
			
		}catch(ClassNotFoundException msg){
			
			msg.printStackTrace();
			
		}catch(InstantiationException msg){
			
			msg.printStackTrace();
			
		}catch(IllegalAccessException msg){
			
			msg.printStackTrace();
			
		}catch(InvocationTargetException msg){
			
			msg.printStackTrace();
			
		}finally{
			//TODO://end
		}
		
	}
}

class Person{
	
	private String Name;
	private int Age;
	
	public Person(){
		
		this.Name = "Public: Default";
		this.Age = 0;
	}
	
	public Person(String name,int age){
		
		this.Name = "Public: "+name;
		this.Age = age;
	}
	
	private Person(boolean token){
		
		if(token){
			this.Name = "Private: Me";
			this.Age = 0;
		}else{
			this.Name = "Private: Other";
			this.Age = -1;
		}
	}
	
	public static Person getPerson(){
		
		return new Person(true);
	}
	
	public void getDescription(){
		
		System.out.println(this.Name+"  "+this.Age);
	}
}