[php]php设计模式 FlyWeight (享元模式)

<?php
 2 /**
 3  * 享元模式
 4  *
 5  * 运用享元技术有效的支持大量细粒度的对象
 6 */
 7 class CD 
 8 {
 9 private$_title=null;
10 private$_artist=null;
11 
12 publicfunction setTitle($title)
13     {
14 $this->_title =$title;
15     }
16 
17 publicfunction getTitle()
18     {
19 return$this->_title;
20     }
21 
22 publicfunction setArtist($artist)
23     {
24 $this->_artist =$artist;
25     }
26 
27 publicfunction getArtist($artist)
28     {
29 return$this->_artist;
30     }
31 }
32 
33 class Artist
34 {
35 private$_name;
36 
37 publicfunction __construct($name)
38     {
39 echo"construct ".$name."<br/>";
40 $this->_name =$name;
41     }
42 
43 publicfunction getName()
44     {
45 return$this->_name;
46     }
47 }
48 
49 class ArtistFactory
50 {
51 private$_artists=array();
52 
53 publicfunction getArtist($name)
54     {
55 if(isset($this->_artists[$name]))
56         {
57 return$this->_artists[$name];
58         } else {
59 $objArtist=new Artist($name);
60 $this->_artists[$name] =$objArtist;
61 return$objArtist;
62         }
63     }
64 }
65 
66 $objArtistFactory=new ArtistFactory();
67 
68 $objCD1=new CD();
69 $objCD1->setTitle("title1");
70 $objCD1->setArtist($objArtistFactory->getArtist('artist1'));
71 
72 $objCD2=new CD();
73 $objCD2->setTitle("title2");
74 $objCD2->setArtist($objArtistFactory->getArtist('artist2'));
75 
76 $objCD3=new CD();
77 $objCD3->setTitle("title3");
78 $objCD3->setArtist($objArtistFactory->getArtist('artist1'));