@Override
    protected User clone() throws CloneNotSupportedException {
        // return new User(this.getName(),address);//浅拷贝
        return new User(this.getName(),(Address)address.clone());//深拷贝
    }

clone一个对象

定义

创建一个对象相当复杂，或者对象中的值很多，创建后需要重复复制。那么这时候就可以使用现成的对象Clone一个出来，在根据具体差异进行修改即可。

方式

1. 通过实现Clone方法(深拷贝和前拷贝之分)，可以手动赋值也可以使用映射
2. 将原始对象 转换 为json字符串，在把json字符串 转换为一个对象
3. 将原始对象 转换 为二进制字节流，在把二进制字节流 转换为一个对象

实现

1. 实体实现Object.clone方法

protected native java.lang.Object clone() throws java.lang.CloneNotSupportedException;

2. 实现Serializable接口，进行两次序列化就行

public static void main(String[] args) throws Exception {

        User u = new User("name1",new Address("address1"));
        User u2 = u.clone();
        
        System.out.println("u2:"+u2.toString());


         
        ByteArrayOutputStream bos = new ByteArrayOutputStream(); 
        ObjectOutputStream oos = new ObjectOutputStream(bos); 
        oos.writeObject(u); 

         
        ByteArrayInputStream bis = new ByteArrayInputStream(bos.toByteArray()); 
        ObjectInputStream ois = new ObjectInputStream(bis); 
        User u3 =  (User)ois.readObject(); 
        
        System.out.println("u3:"+u3.toString());
        u3.getAddress().setAddress("address3");
        System.out.println("u:"+u.toString());

}


public class User implements Serializable{
    
    private String name;
    private Address address;
    
    public User(String name, Address address) {
        super();
        this.name = name;
        this.address = address;
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public Address getAddress() {
        return address;
    }
    public void setAddress(Address address) {
        this.address = address;
    }
    
    @Override
    protected User clone() throws CloneNotSupportedException {
//        return new User(this.getName(),address);//浅拷贝
        return new User(this.getName(),(Address)address.clone());//深拷贝
    }
    
    @Override
    public String toString() {
        return "User [name=" + name + ", address=" + (address!=null?address.toString():null) + "]";
    }
    
}