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  • java基础入门-构造器-构造函数

    package com.ray.testobject;
    
    public class Person {
    	private String name;
    	private int age;
    
    	public Person() {
    	}
    
    	public Person(String name, int age) {
    		this.name = name;
    		this.age = age;
    	}
    
    	public String getName() {
    		return name;
    	}
    
    	public void setName(String name) {
    		this.name = name;
    	}
    
    	public int getAge() {
    		return age;
    	}
    
    	public void setAge(int age) {
    		this.age = age;
    	}
    
    	public static void main(String[] args) {
    		Person bill = new Person("bill", 2);
    		Person temp = bill;
    		bill = new Person("jack", 3);
    		System.out.println(bill.equals(temp));
    	}
    }


    输出:false


    通过上面的代码,可以看到,构造函数必须使用new,而且对于同一个对象,不能够再次使用new来改变里面的属性域。


    package com.ray.testobject;
    
    public class Person {
    	private String name;
    	private int age;
    
    	public Person() {
    	}
    
    	public Person(String name, int age) {
    		this.name = name;
    		this.age = age;
    	}
    
    	public String getName() {
    		return name;
    	}
    
    	public void setName(String name) {
    		this.name = name;
    	}
    
    	public int getAge() {
    		return age;
    	}
    
    	public void setAge(int age) {
    		this.age = age;
    	}
    
    	public static void main(String[] args) {
    		Person bill = new Person("bill", 2);
    		Person temp = bill;
    		// bill = new Person("jack",4);注释这一句
    		// 使用里面的方法改变内容
    		bill.setAge(4);
    		bill.setName("jack");
    		System.out.println(bill.equals(temp));
    		System.out.println(bill.getName());
    	}
    }


    输出:
    true
    jack


    我们再来看上面的代码,只是改动了两句,但是他指向的对象没有变化,只是通过里面的方法,把对象的属性域给改变了


    
        
            

    版权声明:本文为博主原创文章,未经博主允许不得转载。

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  • 原文地址:https://www.cnblogs.com/raylee2007/p/4774583.html
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