Tutorial 6_原型模式

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

 

 

深克隆

 

 

代码：

 

 

Java
浅克隆：
2.1 Attachment.java
package qiankelong;

public class Attachment {

    public void download()
         {
             System.out.println("复制向量");    
         }
    
}

2.2 Client.java
package qiankelong;

public class Client {

    public static void main(String a[])
    {
             
             Vector vector,copyVector;
             vector=new Vector();
             int[] arr= {2,8,3,6};
             vector.setArray(arr);
             System.out.println("浅克隆示例：");
             copyVector=(Vector)vector.clone();
             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());            
    }
    
}

2.3 Vector.java
package qiankelong;

import java.util.Arrays;
 
public class Vector implements Cloneable 
{
    
     private int[] array; 
     private Attachment attachment=null;
     
     public Vector()
     {
        
         this.attachment=new Attachment();
     }     
     
     public Object clone()
     {
         Vector clone=null;
         try
         {
             clone=(Vector)super.clone();        
         }
         catch(CloneNotSupportedException e)
         {
             System.out.println("Clone failure!");
         }
         return clone;
     }
     
     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;
     }
     
}

 

 

 

深克隆
2.4    Attachment.java
package shenkelong;

import java.io.*;

public class Attachment implements Serializable
{
    public void download()
    {
        System.out.println("复制向量");
    }
}

2.5    Vector.java
package shenkelong;

import java.io.*;
import java.util.*;

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;
    }
    
}

2.6    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());    
        
    }
    
}

 

 

C++
#include<cmath>
#include<iostream>
using namespace std;

class Vector{
private:
    double *array =new double[4];
    double length;
public:
    Vector(double arr[4])
    {
        this->array[0] = arr[0];
        this->array[1] = arr[1];  
        this->array[2] = arr[2];
        this->array[3] = arr[3];
        this->length = sqrt(((arr[0] - arr[1])*(arr[0] - arr[1])) + ((arr[2] - arr[3])*(arr[2] - arr[3])));
    }
    ~Vector()
    {
        delete[]array;
        this->length = 0;
    }
    Vector* clone()
    {
        return new Vector(*this);
    }

    Vector(const Vector& vector)
    {
        //浅克隆
        this->array = vector.array;
        this->length = vector.length;

    }
    void show()
    {
        cout << "向量长度：" << this->length << endl;
    }
};
int main()
{
    double s[4] = { 1, 2, 3, 4 };
    Vector* v1 = new Vector(s);
    Vector* v2 = v1->clone();
    v1->show();
    v2->show();
    return 0;
}