Java-clone总结

浅拷贝：

（1） 基本的数据类型（String）是会拷贝复制一份新的对象

（2）引用对象还是引用同一份对象。

浅拷贝示例代码：

public class Info {
    public int idnumber;
    public int getIdnumber() {
    return idnumber;
    }
    public void setIdnumber(int idnumber) {
        this.idnumber = idnumber;
    }
}
public class Person  implements Cloneable{
    private int age;
    private String nameString;
    public Info info;
    public Info getInfo() {
        return info;
    }
    public void setInfo(Info info) {
        this.info = info;
    }
    public int getAge() {
        return age;
    }
    public void setAge(int age) {
        this.age = age;
    }
    public String getNameString() {
        return nameString;
    }
    public void setNameString(String nameString) {
        this.nameString = nameString;
    }
    public String toString()
    {
        return "name:"+nameString+",age:"+age+",idnumber"+info.idnumber;
    }
    public Object clone()
    {
        Person person=null;
        try {
            person=(Person)super.clone(); //浅拷贝
            //person.info=(Info)info.clone();
        } catch (CloneNotSupportedException e) {
        // TODO 自动生成的 catch 块
        e.printStackTrace();
        }
        return person;
    }
}

public class Hello {
public static void main(String[] args) {
// TODO 自动生成的方法存根
Info info=new Info();
info.setIdnumber(100);
Person person1=new Person();
person1.setAge(10);
person1.setNameString("tiantian");
person1.info=info;
Person person2=(Person)person1.clone();
person2.setNameString("hello");
person2.setAge(20);
person2.info.setIdnumber(200);
System.out.println("person2"+person2);
System.out.println("person1"+person1);
}

}

person2name:hello,age:20,idnumber200
person1name:tiantian,age:10,idnumber200

深拷贝：

（1）对存在的引用类型也进行拷贝，浅拷贝与深拷贝的代码还是有不同点的。

深拷贝代码示例：

public class Info implements Cloneable {//Info也进行拷贝
    public int idnumber;
    public int getIdnumber() {
        return idnumber;
    }
    public void setIdnumber(int idnumber) {
        this.idnumber = idnumber;
    }
    public Object clone()
    {
        Info info=null;
        try {
            info=(Info)super.clone();
        } catch (CloneNotSupportedException e) {
        // TODO 自动生成的 catch 块
        e.printStackTrace();
        }
        return info;
    }
}

public class Person  implements Cloneable{

private int age;
    private String nameString;
    public Info info;

    public Info getInfo() {
        return info;
    }
    public void setInfo(Info info) {
        this.info = info;
    }
    public Person() {
        // TODO 自动生成的构造函数存根

    }
    public int getAge() {
        return age;
    }
    public void setAge(int age) {
        this.age = age;
    }
    public String getNameString() {
        return nameString;
    }
    public void setNameString(String nameString) {
        this.nameString = nameString;
    }

    public String toString()
    {
        return "name:"+nameString+",age:"+age+",idnumber"+info.idnumber;
    }

    public Object clone()
    {
        Person person=null;
        try {
            person=(Person)super.clone(); //浅拷贝
            person.info=(Info)info.clone();//加上这一句就变成了深拷贝，对对象引用也进行一次拷贝
            } catch (CloneNotSupportedException e) {
            // TODO 自动生成的 catch 块
            e.printStackTrace();
            }
        return person;
    }
}

person2name:hello,age:20,idnumber200
person1name:tiantian,age:10,idnumber100

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