I have an object and this object also includes other objects, like this

Student :

    public class Student implements Cloneable {
    public int id;
    public String name;
    public List<Integer,java,spring,spring-boot,object,clone"/>
	














    

		

        

            
            时间戳
        

		

		

        
		

    
















	
首页  > 解决方案 > 如何深拷贝列表

I have an object and this object also includes other objects, like this


Student :


    public class Student implements Cloneable {
    public int id;
    public String name;
    public List<Integer












java - 如何深拷贝列表

I have an object and this object also includes other objects, like this


Student :


    public class Student implements Cloneable {
    public int id;
    public String name;
    public List<Integer





问题描述



I have an object and this object also includes other objects, like this


Student :


    public class Student implements Cloneable {
    public int id;
    public String name;
    public List<Integer> score;
    public Address address;

    ......

    @Override
    protected Object clone() throws CloneNotSupportedException {
        return super.clone();
    }

}



Address :


public class Address implements Serializable,Cloneable{
    public String type;
    public String value;

    ......

    @Override
    protected Object clone() throws CloneNotSupportedException {
        return super.clone();
    }

}



Now i have a List\<Student> studentsList  How can I deep copy studentsList？How can I copy studentsList if there are other objects in Address?









You need to implement a correct clone() method like


public class Student implements Cloneable {
    public int id;
    public String name;
    public List<Integer> score;
    public Address address;

    ......

    @Override
    protected Object clone() throws CloneNotSupportedException {
        Student std = new Student();
        std.id = this.id; // Immutable
        std.name = this.name; // Immutable
        std.score = this.score.stream().collect(Collectors.toList()); // Integer is immutable
        std.address = (Adress) this.address.clone();
        return std;
    }



标签： javaspringspring-bootobjectclone


解决方案









您需要实施正确的clone()方法，例如


public class Student implements Cloneable {
    public int id;
    public String name;
    public List<Integer> score;
    public Address address;

    ......

    @Override
    protected Object clone() throws CloneNotSupportedException {
        Student std = new Student();
        std.id = this.id; // Immutable
        std.name = this.name; // Immutable
        std.score = this.score.stream().collect(Collectors.toList()); // Integer is immutable
        std.address = (Adress) this.address.clone();
        return std;
    }











推荐阅读