Java 深浅拷贝

时间:2023-03-09 05:02:33
Java 深浅拷贝

2016-07-02

1深拷贝:不仅拷贝对象,而且对象所引用地址的内容一块拷贝。改变一个对象的某个属性,并不影响另一个对象所引用的内容。

2浅拷贝:仅拷贝对象本身,并不对所引用(所指的)内容进行拷贝,当对一个对象做改变的时候,另一个对象的相应属性也做同样的改变。

3深拷贝要重写clone函数。implements Cloneable。

浅拷贝:

Java 深浅拷贝

深拷贝

Java 深浅拷贝

这个代码是借鉴的(记得是这样的,标注---借鉴资源)

class Professor0 implements Cloneable {
String name;
int age; Professor0(String name, int age) {
this.name = name;
this.age = age;
} public Object clone() throws CloneNotSupportedException {
return super.clone();//调用父类的
}
} class Student0 implements Cloneable {
String name;// 常量对象。
int age;
Professor0 p;// 学生1和学生2的引用值都是一样的。 Student0(String name, int age, Professor0 p) {
this.name = name;
this.age = age;
this.p = p;
} /* public Object clone() {
Student0 o = null;
try {
o = (Student0) super.clone();
} catch (CloneNotSupportedException e) {
System.out.println(e.toString());
} return o;
}*/
} public class qiancopy {
public static void main(String[] args) {
Professor0 p = new Professor0("perfesser0", 50);
Student0 s1 = new Student0("stu1", 18, p);
System.out.println("学生s1的姓名:" + s1.name + "\n学生s1教授的姓名:" + s1.p.name + "," + "\n学生s1教授的年纪" + s1.p.age+"......end");// 学生1的教授 Student0 s2 =s1;
s2.p.name = "s2copys";
s2.p.age = 30;
s2.name = "s2";
s2.age = 45;
System.out.println("学生s1的姓名:" + s1.name+ "\n学生s1的年龄:" + s1.age + "\n学生s1教授的姓名:" + s1.p.name + "," + "\n学生s1教授的年纪" + s1.p.age+"...end");
System.out.println("学生s2的姓名:" + s2.name+ "\n学生s2的年龄:" + s2.age + "\n学生s2教授的姓名:" + s2.p.name + "," + "\n学生s2教授的年纪" + s2.p.age+"...end");// 学生1的教授 }
}
class Professor implements Cloneable {
String name;
int age; Professor(String name, int age) {
this.name = name;
this.age = age;
} public Object clone() {
Object o = null;
try {
o = super.clone();
} catch (CloneNotSupportedException e) {
System.out.println(e.toString());
}
return o;
}
} class Student implements Cloneable {
String name;
int age;
Professor p; Student(String name, int age, Professor p) {
this.name = name;
this.age = age;
this.p = p;
} public Object clone() {
Student o = null;
try {
o = (Student) super.clone();//stu 深拷贝
} catch (CloneNotSupportedException e) {
System.out.println(e.toString());
}
o.p = (Professor) p.clone();//professer深拷贝
return o;
}
} public class shencopy {
public static void main(String args[]) { Professor p = new Professor("professer1", 50);
Student s1 = new Student("stu1", 18, p);
System.out.println("学生s1的姓名:" + s1.name+ "\n学生s1的年龄:" + s1.age + "\n学生s1教授的姓名:" + s1.p.name + "," + "\n学生s1教授的年纪" + s1.p.age+"......end");// 学生1的教授 Student s2 = (Student) s1.clone();
s2.name = "s2copys";
s2.age = 30;
s2.p.name = "stu2";
s2.p.age = 30;
System.out.println("学生s1的姓名:" + s1.name+ "\n学生s1的年龄:" + s1.age + "\n学生s1教授的姓名:" + s1.p.name + "," + "\n学生s1教授的年纪" + s1.p.age+"......end");// 学生1的教授
System.out.println("学生s2的姓名:" + s2.name+ "\n学生s2的年龄:" + s2.age + "\n学生s2教授的姓名:" + s2.p.name + "," + "\n学生s2教授的年纪" + s2.p.age+"......end");// 学生2的教授 }
}