原型模式顾名思义，以一个对象为原型，进行克隆，复制操作，产生一个和原型相似的对象。下面用的例子是以Java中浅拷贝和深拷贝为例。
浅拷贝:被克隆对象的所有变量都与原来对象有相同的值，而所有的对其他对象的引用仍然指向原来的对象。
上面说的很抽象，下面通过简单堆栈图描述:(图与示例代码相对应,man对象在person类中被引用)
深拷贝:被克隆对象的所有变量都与原来的对象有相同的值，除去那些引用其他对象的变量。那些引用其他对象的变量将指向被克隆过的新对象，而不再是原有的那些被引用的对象。
示例代码:
- public class Man implements Cloneable{
- private String name;
- private int age;
- Man m;
- public Man(int age,String name){
- this.age = age;
- this.name = name;
- }
- public Object clone(){
- try {
- m = (Man) super.clone();
- } catch (CloneNotSupportedException e) {
- e.printStackTrace();
- }
- return m;
- }
- public void setAge(int age){
- this.age = age;
- }
- public void setName(String name){
- this.name = name;
- }
- public int getAge(){
- return age;
- }
- public String getName(){
- return name;
- }
- }
- public class Person implements Cloneable {
- private int age;
- private String name;
- Man man;
- String address = new String("CQ");
- public Person(int age,String name,Man man){
- this.age = age;
- this.name = name;
- this.man = man;
- }
- /*
- *浅拷贝
- */
- public Person clone(){
- Person person = null;
- try {
- person = (Person) super.clone();
- }catch (CloneNotSupportedException e){
- e.printStackTrace();
- }
- return person;
- }
- /*
- *深拷贝
- */
- public Person deepclone(){
- Person person = null;
- try{
- person = (Person)super.clone();
- person.man = (Man)person.man.clone();//同样拷贝引用的对象
- }catch (CloneNotSupportedException e){
- e.printStackTrace();
- }
- return person;
- }
- public void setAge(int age){
- this.age = age;
- }
- public void setName(String name){
- this.name = name;
- }
- public int getAge(){
- return age;
- }
- public String getName(){
- return name;
- }
- public static void main(String[] args){
- Man man = new Man(1,"Man");
- /*
- *浅拷贝
- */
- System.out.print("拷贝前Man:\n"+"age="+man.getAge()+",name="+man.getName()+"\n");
- Person person = new Person(2,"Person",man);
- System.out.print("拷贝前Person:\n"+"age="+person.getAge()+",name="+person.getName()+"\n");
- Person person1 = person.clone();
- person1.setAge(22);
- person1.setName("Person222");
- person1.man.setAge(11);
- person1.man.setName("Man11");
- System.out.print("拷贝前Man:\n"+"age="+man.getAge()+",name="+man.getName()+"\n");
- System.out.print("拷贝后Man:\n"+"age="+person1.man.getAge()+",name="+person1.man.getName()+"\n");//Man引用拷贝后对值得修改，影响到修改之前的值
- System.out.print("拷贝后Person:\n"+"age="+person1.getAge()+",name="+person1.getName()+"\n");
- /*
- *深拷贝
- */
- System.out.println("=================================================");
- Man mandeep = new Man(1,"Man");
- Person persondeep = new Person(2,"Person",mandeep);
- Person person2 = person.deepclone();
- System.out.print("深拷贝前Man:\n"+"age="+mandeep.getAge()+",name="+mandeep.getName()+"\n");
- System.out.print("深拷贝前Person:\n"+"age="+person.getAge()+",name="+person.getName()+"\n");
- person2.setAge(22);
- person2.setName("Person222");
- person2.man.setAge(11);
- person2.man.setName("Man11");
- System.out.print("深拷贝前Man:\n"+"age="+mandeep.getAge()+",name="+mandeep.getName()+"\n");
- System.out.print("深拷贝后Man:\n"+"age="+man.getAge()+",name="+man.getName()+"\n");
- System.out.print("深拷贝后Person:\n"+"age="+person1.getAge()+",name="+person2.getName()+"\n");
- }
- }
关于java的深克隆和浅克隆详细介绍可参考:http://blog.csdn.net/pony_maggie/article/details/52091588
来自 “ ITPUB博客 ” ，链接：https://blog.itpub.net/29876893/viewspace-2140453/ ，如需转载，请注明出处，否则将追究法律责任。
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