public class Sheep implements Cloneable {
private String name;
private int age;
private String color;
public Sheep(String name,int age,String color){
this.name = name;
this.age = age;
this.color = color;
}
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 String getColor() {
return color;
}
public void setColor(String color) {
this.color = color;
}
@Override
protected Object clone() {
Sheep sheep = null;
try {
sheep = (Sheep) super.clone();
} catch (CloneNotSupportedException e) {
e.printStackTrace();
}
return sheep;
}
}
在spring框架的应用
1、beans.xml
<bean id="id01" class="com.atguigu.spring.bean.Monster" scope="prototype" />
2、Test.java
ApplicationContext applicationContext = new ClassPathXmlApplicationContext("beans.xml");
Object bean = applicationContext.getBean("id01");
System.out("bean"+bean);
对于数据类型是基本数据类型的成员变量,浅拷贝会直接进行值的传递,也就是属性值复制一份给新的对象。
对于数据类型是引用数据类型的成员变量,比如说成员变量是某个数组,某个类的对象等,那么浅拷贝会进行引用传递,也就是只是该成员变量的引用值(内存地址)复制一份给新的对象,因为实际上两个对象的该成员变量都指向同一个实例,在这个情况下,在一个对象中修改成员变量会影响到另一个对象的该成员变量值
浅拷贝是使用,默认的clone()方法来实现。
public class Person implements Cloneable{
public String pname;
public int page;
public Address address;
public Person() {}
public Person(String pname,int page){
this.pname = pname;
this.page = page;
this.address = new Address();
}
@Override
protected Object clone() throws CloneNotSupportedException {
return super.clone();
}
public void setAddress(String provices,String city ){
address.setAddress(provices, city);
}
public void display(String name){
System.out.println(name+":"+"pname=" + pname + ", page=" + page +","+ address);
}
public String getPname() {
return pname;
}
public void setPname(String pname) {
this.pname = pname;
}
public int getPage() {
return page;
}
public void setPage(int page) {
this.page = page;
}
}
复制对象的所有基本数据类型的成员变量值
为所有引用数据类型的成员变量中申请存储空间,并复制每个引用数据类型成员变量所引用的对象,直到该对象可达到的所有对象,也就是说,对象进行深拷贝要对整个对象进行拷贝
深拷贝实现方式1:重写clone方法来实现深拷贝
public class Address implements Cloneable{
private String provices;
private String city;
public void setAddress(String provices,String city){
this.provices = provices;
this.city = city;
}
@Override
public String toString() {
return "Address [provices=" + provices + ", city=" + city + "]";
}
@Override
protected Object clone() throws CloneNotSupportedException {
return super.clone();
}
}
Person.class 的 clone() 方法:
@Override
protected Object clone() throws CloneNotSupportedException {
Person p = (Person) super.clone();
p.address = (Address) address.clone();
return p;
}
深拷贝实现方式2:通过对象序列化实现深拷贝
//深度拷贝
public Object deepClone() throws Exception{
// 序列化
ByteArrayOutputStream bos = new ByteArrayOutputStream();
ObjectOutputStream oos = new ObjectOutputStream(bos);
oos.writeObject(this);
// 反序列化
ByteArrayInputStream bis = new ByteArrayInputStream(bos.toByteArray());
ObjectInputStream ois = new ObjectInputStream(bis);
return ois.readObject();
}
原文:https://www.cnblogs.com/It-smallstudent/p/14788028.html