src/charactermanaj/graphics/io/ImageCache.java

   1 package charactermanaj.graphics.io;\r
   2 \r
   3 import java.awt.image.BufferedImage;\r
   4 import java.lang.ref.Reference;\r
   5 import java.lang.ref.ReferenceQueue;\r
   6 import java.lang.ref.SoftReference;\r
   7 import java.util.HashMap;\r
   8 import java.util.logging.Level;\r
   9 import java.util.logging.Logger;\r
  10 \r
  11 \r
  12 /**\r
  13  * 画像のキャッシュ.<br>\r
  14  * キャッシュは自動的にガベージコレクタにより回収されます.<br>\r
  15  * ただし、{@link #unlockImages()}が呼び出されるまで、{@link #set(Object, BufferedImage)}されたイメージは\r
  16  * ガベージコレクトの対象にはなりません。\r
  17  * @author seraphy\r
  18  *\r
  19  * @param <K>\r
  20  */\r
  21 public class ImageCache<K> {\r
  22 \r
  23         private static final Logger logger = Logger.getLogger(ImageCache.class.getName());\r
  24 \r
  25         private static final ImageCacheMBeanImpl imageCacheMBean = ImageCacheMBeanImpl.getSingleton();\r
  26 \r
  27         private HashMap<K, BufferedImageWithKeyReference<K>> lockedImages\r
  28                 = new HashMap<K, BufferedImageWithKeyReference<K>>();\r
  29 \r
  30         private ReferenceQueue<LoadedImage> queue = new ReferenceQueue<LoadedImage>();\r
  31 \r
  32         private HashMap<K, BufferedImageWithKeyReference<K>> caches\r
  33                 = new HashMap<K, BufferedImageWithKeyReference<K>>();\r
  34 \r
  35         public ImageCache() {\r
  36             imageCacheMBean.incrementInstance();\r
  37         }\r
  38 \r
  39         @Override\r
  40         protected void finalize() throws Throwable {\r
  41             clear();\r
  42         imageCacheMBean.decrementInstance();\r
  43             super.finalize();\r
  44         }\r
  45 \r
  46         public LoadedImage get(K key) {\r
  47                 if (key == null) {\r
  48                         return null;\r
  49                 }\r
  50                 synchronized (caches) {\r
  51                         BufferedImageWithKeyReference<K> ref = caches.get(key);\r
  52                         LoadedImage img = null;\r
  53                         if (ref != null) {\r
  54                                 img = ref.get();\r
  55                         }\r
  56                         imageCacheMBean.incrementReadCount(img != null);\r
  57                         sweep();\r
  58                         return img;\r
  59                 }\r
  60         }\r
  61 \r
  62         public void set(K key, LoadedImage img) {\r
  63                 if (key == null) {\r
  64                         return;\r
  65                 }\r
  66                 synchronized (caches) {\r
  67                     // 現在キャッシュされているものがあれば、いったん解放する.\r
  68             BufferedImageWithKeyReference<K> ref = caches.get(key);\r
  69             if (ref != null) {\r
  70                 ref.enqueue();\r
  71             }\r
  72 \r
  73             if (img == null) {\r
  74                                 if (logger.isLoggable(Level.FINE)) {\r
  75                                         logger.log(Level.FINE, "remove cache: " + key);\r
  76                                 }\r
  77                                 caches.remove(key);\r
  78 \r
  79                         } else {\r
  80                                 BufferedImageWithKeyReference<K> cacheData = new BufferedImageWithKeyReference<K>(key, img, queue);\r
  81                                 lockedImages.put(key, cacheData);\r
  82                                 caches.put(key, cacheData);\r
  83 \r
  84                                 imageCacheMBean.cacheIn(cacheData.getImageSize());\r
  85                         }\r
  86 \r
  87             // 解放済みのアイテムエントリを除去する.\r
  88             sweep();\r
  89                 }\r
  90         }\r
  91 \r
  92         public void unlockImages() {\r
  93                 synchronized (caches) {\r
  94                         lockedImages.clear();\r
  95                         sweep();\r
  96                 }\r
  97         }\r
  98 \r
  99         /**\r
 100          * すべてのエントリをキャッシュアウトしてクリアする.\r
 101          */\r
 102         public void clear() {\r
 103             synchronized (caches) {\r
 104             lockedImages.clear();\r
 105                 for (BufferedImageWithKeyReference<K> ref : caches.values()) {\r
 106                     ref.enqueue();\r
 107                 }\r
 108             sweep();\r
 109             caches.clear();\r
 110             }\r
 111         }\r
 112 \r
 113         public void sweep() {\r
 114                 synchronized (caches) {\r
 115                         // ガベージコレクト済みアイテムを除去する\r
 116                         Reference<?> ref = null;\r
 117                         boolean removed = false;\r
 118                         while ((ref = queue.poll()) != null) {\r
 119                                 @SuppressWarnings("unchecked")\r
 120                                 BufferedImageWithKeyReference<K> r =\r
 121                                     (BufferedImageWithKeyReference<K>) ref;\r
 122                                 K key = r.getKey();\r
 123                                 if (key != null) {\r
 124                                         if (caches.get(key).get() == null) {\r
 125                                                 if (logger.isLoggable(Level.FINE)) {\r
 126                                                         logger.log(Level.FINE, "removed cache: " + key);\r
 127                                                 }\r
 128                                                 removed = true;\r
 129                                                 caches.remove(key);\r
 130                                         }\r
 131                                 }\r
 132 \r
 133                                 int imageSize = r.getImageSize();\r
 134                                 imageCacheMBean.cacheOut(imageSize);\r
 135                         }\r
 136                         if (removed) {\r
 137                                 if (logger.isLoggable(Level.FINE)) {\r
 138                                         logger.log(Level.FINE,\r
 139                                                         "cache[" + Integer.toHexString(this.hashCode())\r
 140                                                                         + "] size:" + caches.size());\r
 141                                 }\r
 142                         }\r
 143                 }\r
 144         }\r
 145 }\r
 146 \r
 147 /**\r
 148  * キー情報つきSoftReference\r
 149  * @author seraphy\r
 150  *\r
 151  * @param <K> キー\r
 152  */\r
 153 class BufferedImageWithKeyReference<K> extends SoftReference<LoadedImage> {\r
 154 \r
 155         private final K key;\r
 156 \r
 157         private final int imageSize;\r
 158 \r
 159         public BufferedImageWithKeyReference(K key, LoadedImage img, ReferenceQueue<? super LoadedImage> queue) {\r
 160                 super(img, queue);\r
 161                 this.key = key;\r
 162                 this.imageSize = (img == null) ? 0 : img.getImageSize();\r
 163         }\r
 164 \r
 165         public K getKey() {\r
 166                 return key;\r
 167         }\r
 168 \r
 169         public int getImageSize() {\r
 170         return imageSize;\r
 171     }\r
 172 }\r