原型模式——Java实现

问题描述：

向量的原型

用C++完成数学中向量的封装，其中，用指针和动态申请支持向量长度的改变，使用浅克隆和深克隆复制向量类，比较这两种克隆方式的异同。

浅克隆类图：

浅克隆Java代码：

 1 //Vector.java
 2 package qiankelong;
 3 
 4 import java.util.Arrays;
 5 
 6 public class Vector implements Cloneable 
 7 {
 8     private int[] array;
 9     
10     private Attachment attachment=null;
11     
12     public Vector()
13     {
14         
15         this.attachment=new Attachment();
16     }     
17     
18     public Object clone()
19     {
20         Vector clone=null;
21         try
22         {
23             clone=(Vector)super.clone();        
24         }
25         catch(CloneNotSupportedException e)
26         {
27             System.out.println("Clone failure!");
28         }
29         return clone;
30     }
31     
32     public Attachment getAttachment()
33     {
34         return this.attachment;
35     }
36     
37     public void display()
38     {
39             System.out.println(Arrays.toString(array));    
40     }
41 
42     public int[] getArray() {
43         return array;
44     }
45 
46     public void setArray(int[] array) {
47         this.array = array;
48     }
49     
50 }
51 //Attachment.java
52 package qiankelong;
53 public class Attachment
54 {
55     public void download()
56     {
57         System.out.println("复制向量");    
58     }
59 }
60 //Client.java
61 package qiankelong;
62 public class Client
63 {
64     public static void main(String a[])
65     {
66         
67         Vector vector,copyVector;
68         vector=new Vector();
69         int[] arr= {2,8,3,6};
70         vector.setArray(arr);
71         System.out.println("浅克隆示例：");
72         copyVector=(Vector)vector.clone();
73         System.out.print("vector：");
74         vector.display();
75         System.out.print("copyVector：");
76         copyVector.display();
77         System.out.println("vector==copyVector?");
78         System.out.println(vector==copyVector);
79         
80         System.out.println("vector.getAttachment==copyVector.getAttachment?"); 
81         System.out.println(vector.getAttachment()==copyVector.getAttachment());            
82     }
83 }

浅克隆运行结果：

深克隆类图：

深克隆Java代码：

//Vector.java
package shenkelong;
import java.io.*;
import java.util.Arrays;

public class Vector implements Serializable 
{
	private int[] array;
	private Attachment attachment=null;
	
	public Vector()
	{
		this.attachment=new Attachment();
	}
	
	public Object deepClone() throws IOException, ClassNotFoundException, OptionalDataException
	{
		//将对象写入流中
		ByteArrayOutputStream bao=new ByteArrayOutputStream();
		ObjectOutputStream oos=new ObjectOutputStream(bao);
		oos.writeObject(this);
		
		//将对象从流中取出
		ByteArrayInputStream bis=new ByteArrayInputStream(bao.toByteArray());
		ObjectInputStream ois=new ObjectInputStream(bis);
		return(ois.readObject());
	}
	
	public Attachment getAttachment()
	{
		return this.attachment;
	}
	
	public void display()
	{
			System.out.println(Arrays.toString(array));	
	}

	public int[] getArray() {
		return array;
	}

	public void setArray(int[] array) {
		this.array = array;
	}
}
//Attachment.java
package shenkelong;
import java.io.*;

public class Attachment implements Serializable
{
    public void download()
    {
    	System.out.println("复制向量");	
    }
}
//Client.java
package shenkelong;
public class Client
{
	public static void main(String a[])
	{
		Vector vector,copyVector=null;
		
		vector=new Vector();
		int[] arr= {2,8,3,6};
		vector.setArray(arr);
		System.out.println("深克隆示例：");
		
		try{
		    copyVector=(Vector)vector.deepClone();	
		}
		catch(Exception e)
	    {
	   		e.printStackTrace();
	    }	
		System.out.print("vector：");
		vector.display();
		System.out.print("copyVector：");
		copyVector.display();
		System.out.println("vector==copyVector?");
		System.out.println(vector==copyVector);
		
		System.out.println("vector.getAttachment==copyVector.getAttachment?"); 
		System.out.println(vector.getAttachment()==copyVector.getAttachment());			
	}
}