java闭包与对象克隆

朴灿烈づ我的快乐病毒、 2022-02-02 21:23 127阅读 0赞

### 测试闭包与浅克隆 ###

/**
     * 测试闭包
     *
     */
    public class BiBaoTest {
    	public void testBiBao(){
    		
    		User user = new User("张三",18);
    		System.out.println("改变前"+user.toString());
    		change(user);
    		System.out.println("改变后"+user.toString());
    	}
    	
    	public void change(User user){
    		//第一种：直接改变值，不可行
    		//user.setUsername("李四");
    		//user.setAge(20);
    		
    		//第二种：new一个新对象，指向原来对象，还是不行
    		/*User aa=new User();
    		aa=user;
    		aa.setUsername("李四");
    		aa.setAge(20);
    		System.out.println("新对象"+aa.toString());*/
    		
    		//第三种：克隆对象
    		User aa = (User)user.clone();
    		aa.setUsername("李四");
    		aa.setAge(20);
    		System.out.println("克隆的对象"+aa.toString());
    		
    	}
    	
    	
        public static void main( String[] args ){
            new BiBaoTest().testBiBao();
        	
        }
    }
    
    class User implements Cloneable{
    	private String username;
    	private int age;
    	public String getUsername() {
    		return username;
    	}
    	public void setUsername(String username) {
    		this.username = username;
    	}
    	public int getAge() {
    		return age;
    	}
    	public void setAge(int age) {
    		this.age = age;
    	}
    	public User(String username, int age) {
    		super();
    		this.username = username;
    		this.age = age;
    	}
    	public User() {
    		super();
    		
    	}
    	@Override
    	public String toString() {
    		return "User [username=" + username + ", age=" + age + "]";
    	}
    	@Override
    	public Object clone() {
    		
    		try {
    			return super.clone();
    		} catch (CloneNotSupportedException e) {
    			
    			e.printStackTrace();
    		}
    		return null;
    	}
    	
    	
    }

### 测试深克隆 ###

package com.asiainfo.group.main;
    
    /**
     * 深克隆
     *
     */
    public class CloneTest {
    	public void testClone(){
    		Parent p1 = new Parent("张三",40,new Children("张小三", 18));
    		//深克隆
    		Parent p2 = (Parent)p1.clone();
    		
    		System.out.println(p1==p2);//false
    		System.out.println(p1.getChildren()==p2.getChildren());//false
    		
    	}
    	
        public static void main( String[] args ){
            new CloneTest().testClone();
        	
        }
    }
    
    
    
    class Children implements Cloneable{
    	private String name;
    	private int 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 Children(String name, int age) {
    		super();
    		this.name = name;
    		this.age = age;
    	}
    	public Children() {
    		super();
    	}
    	@Override
    	public String toString() {
    		return "Children [name=" + name + ", age=" + age + "]";
    	}
    	
    	@Override
    	protected Object clone() {
    		
    		try {
    			return super.clone();
    		} catch (CloneNotSupportedException e) {
    			
    			e.printStackTrace();
    		}
    		return null;
    	}
    }
    
    
    class Parent implements Cloneable{
    	private String name;
    	private int age;
    	private Children children;
    	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 Children getChildren() {
    		return children;
    	}
    	public void setChildren(Children children) {
    		this.children = children;
    	}
    	
    	public Parent() {
    		super();
    		
    	}
    	public Parent(String name, int age, Children children) {
    		super();
    		this.name = name;
    		this.age = age;
    		this.children = children;
    	}
    	@Override
    	public String toString() {
    		return "Parent [name=" + name + ", age=" + age + ", children=" + children + "]";
    	}
    	
    	@Override
    	public Object clone() {
    		
    		
    		Parent p=null;
    		try {
    			p = (Parent)super.clone();
    		} catch (CloneNotSupportedException e) {
    			
    			e.printStackTrace();
    		}
    		p.children=(Children)children.clone();
    		return p;
    	}
    	
    }