原型模式和深拷贝，浅拷贝 - ToB企服应用市场:ToB评测及商务社交产业平台

public class Sheep {
private String name;
private int age;
private String color;
public Sheep() {
}
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;
}
}
//测试
public class Client {
public static void main(String[] args) {
Sheep sheep = new Sheep("tom", 1, "白色");
Sheep sheep1 = new Sheep(sheep.getName(), sheep.getAge(), sheep.getColor());
Sheep sheep2 = new Sheep(sheep.getName(), sheep.getAge(), sheep.getColor());
Sheep sheep3 = new Sheep(sheep.getName(), sheep.getAge(), sheep.getColor());
/**
* public String toString() {//Object类的toString()方法
* return getClass().getName() + "@" + Integer.toHexString(hashCode());//会输出全类名@符还有16进制的hashCode值
* }
*/
System.out.println(sheep);//输出的对象的hashcode的值不相同，输出对象时，会默认的调用对象的toString()方法
System.out.println(sheep1);
System.out.println(sheep2);
System.out.println(sheep3);
}
}

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public class Sheep implements Cloneable{
private String name;
private int age;
private String color;
private String address = "蒙古羊";
private Sheep friend;
public Sheep() {
}
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;
}
public String getAddress() {
return address;
}
public void setAddress(String address) {
this.address = address;
}
public Sheep getFriend() {
return friend;
}
public void setFriend(Sheep friend) {
this.friend = friend;
}
@Override
public String toString() {
return "Sheep{" +
"name='" + name + '\'' +
", age=" + age +
", color='" + color + '\'' +
", address='" + address + '\'' +
", friend=" + friend +
'}';
}
@Override
protected Object clone() {
Sheep sheep = null;
try{
sheep = (Sheep)super.clone();
}catch (Exception e){
System.out.println(e.getMessage());
}
return sheep;
}
}
public class Client {
public static void main(String[] args) {
Sheep sheep = new Sheep("tom", 1, "白色");
sheep.setFriend(new Sheep("jack",1,"黑色"));
Sheep sheep1 = (Sheep)sheep.clone();
Sheep sheep2 = (Sheep)sheep.clone();
System.out.println("sheep1=" + sheep1 + "sheep1.friend\n" + sheep1.getFriend().hashCode());//输出的hashCode值相同
System.out.println("sheep2=" + sheep2 + "sheep2.friend\n" + sheep2.getFriend().hashCode());
}
}

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//AbstractBeanFactory类doGetBean()的部分代码
else if (mbd.isPrototype()) {//判断当前bean是否是原型类型
// It's a prototype -> create a new instance.
Object prototypeInstance = null;
try {
beforePrototypeCreation(beanName);
prototypeInstance = createBean(beanName, mbd, args);
}
finally {
afterPrototypeCreation(beanName);
}
bean = getObjectForBeanInstance(prototypeInstance, name, beanName, mbd);
}

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public class Money implements Serializable, Cloneable{
private int account;
@Override
protected Object clone() throws CloneNotSupportedException {
return super.clone();
}
}
public class Person implements Serializable, Cloneable {
private String name;
private int age;
private Money money;
private static final long serialVersionID = 1L;
public Person(String name, int age, Money money) {
this.name = name;
this.age = age;
this.money = money;
}
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 Money getMoney() {
return money;
}
public void setMoney(Money money) {
this.money = money;
}
//1.重写clone方法完成深拷贝
//这种方式存在问题，如果一个类中存在引用属性且没有为该属性复制
//就会导致在进行克隆时会出现NullPointException，可以在clone前进行验证解决
@Override
protected Object clone() throws CloneNotSupportedException {
Person person = null;
//1.完成基本数据类型的clone
person = (Person) super.clone();
//2.对引用类型的属性，进行单独处理
person.money = (Money) money.clone();
return person;
}
//方式2 通过对象的序列化和反序列化实现
public Object deepClone() {
ByteArrayOutputStream bos = null;
ObjectOutputStream oos = null;
ByteArrayInputStream bis = null;
ObjectInputStream ois = null;
Object object = null;
try{
bos = new ByteArrayOutputStream();
oos = new ObjectOutputStream(bos);
oos.writeObject(this);//当前对象序列化到对象输出流中
bis = new ByteArrayInputStream(bos.toByteArray());
ois = new ObjectInputStream(bis);//从输出流中反序列化到输入流中
object = ois.readObject();//读取对象
}catch (IOException | ClassNotFoundException e){
e.printStackTrace();
}finally {
try {
bos.close();
oos.close();
bis.close();
ois.close();
} catch (IOException e) {
e.printStackTrace();
}
}
return object;
}
}
//测试
public class TestDeepClone {
public static void main(String[] args) throws CloneNotSupportedException {
Money money = new Money();
Person person = new Person("wind", 27, null);
Person clone = (Person) person.clone();
// Person clone = (Person) person.deepClone();
System.out.println(person.getMoney().hashCode() + "-" + clone.getMoney().hashCode());
}
}

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