原型模式 深拷贝_原型深拷贝

浅拷贝见博客原型模式 浅拷贝
发送邮件，邮件中有附件，深拷贝实现了附件也拷贝了一份。在附件中再加入了一个对象，序列化后也复制了，实验证明深拷贝会将引用对象的引用对象也都复制

public class Test {
    public static void main(String[] args) {
        Email email = new Email(new Attachment());
        Email copyEmail =(Email) email.deepClone();
        System.out.println(email == copyEmail);
        System.out.println(email.equals(copyEmail));
        System.out.println(email.getAttachment() == copyEmail.getAttachment());
        System.out.println(email.getAttachment().equals(copyEmail.getAttachment()));
        System.out.println(email.getAttachment().getCat() == copyEmail.getAttachment().getCat());
    }
}

class Attachment implements Serializable{
    private Cat cat = new Cat();
    public void download(){
        System.out.println("下载附件");
    }

    public Cat getCat() {
        return cat;
    }
}

class Email implements Serializable{
    private Attachment attachment;

    public Email(Attachment attachment) {
        this.attachment = attachment;
    }


    public Object deepClone(){
        try {
            //将对象写入流中
            ByteArrayOutputStream bos = new ByteArrayOutputStream();
            ObjectOutputStream oos = new ObjectOutputStream(bos);
            oos.writeObject(this);
            oos.close();
            //将对象从流中取出
            InputStream bis = new ByteArrayInputStream(bos.toByteArray());
            ObjectInputStream ois = new ObjectInputStream(bis);
            Object o = ois.readObject();
            ois.close();
            return o;
        } catch (IOException e) {
            e.printStackTrace();
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        }
        return null;
    }

    public Attachment getAttachment() {
        return attachment;
    }

    public void display(){
        System.out.println("查看邮件");
    }
}
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60

//Email类没有重写equals方法，所以这里equals和==是一样的，如果是String重写了equals方法的话会返回true的。
输出：false
false
false
false
false