Removed DBBean garbage collector

it it is not needed with WeakReference anymore

src/zutil/db/bean/DBBeanCache.java

@@ -17,17 +17,15 @@ import java.util.logging.Logger;
  */
 class DBBeanCache {
     private static final Logger logger = LogUtil.getLogger();
-    /** This is the time to live for the cached items **/
+    /**
+     * This is the time to live for the cached items
+     **/
     public static final long CACHE_DATA_TTL = 1000 * 60 * 5; // 5 min in ms
-    /** A cache for detecting recursion **/
+    /**
+     * A cache for detecting recursion
+     **/
     private static Map<Class<?>, Map<Long, CacheItem>> cache =
             new ConcurrentHashMap<>();
-    private static ScheduledExecutorService executor;
-
-
-    static {
-        enableBeanGBC(true); // Initiate DBBeanGarbageCollector
-    }
 
     /**
      * A cache container that contains a bean and its last filed update time
@@ -37,74 +35,16 @@ class DBBeanCache {
         public WeakReference<DBBean> bean;
     }
 
-
-
-    /**
-     * This function cancels the internal cache garbage collector in DBBean.
-     * GBC is enabled by default
-     */
-    public static synchronized void enableBeanGBC(boolean enable){
-        if(enable){
-            if( executor == null ){
-                executor = Executors.newSingleThreadScheduledExecutor();
-                executor.scheduleAtFixedRate( new DBBeanGarbageCollector(), CACHE_DATA_TTL, CACHE_DATA_TTL *2, TimeUnit.MILLISECONDS );
-                logger.fine("Bean garbage collection daemon enabled");
-            }
-        }
-        else {
-            if (executor != null) {
-                executor.shutdown();
-                executor = null;
-                logger.fine("Bean garbage collection daemon disabled");
-            }
-        }
-    }
-
-    /**
-     * This class acts as an garbage collector that removes old DBBeans
-     */
-    private static class DBBeanGarbageCollector implements Runnable {
-        public void run() {
-            try {
-                if (cache == null) {
-                    logger.severe("DBBeanSQLResultHandler not initialized, stopping DBBeanGarbageCollector timer.");
-                    enableBeanGBC(false);
-                    return;
-                }
-
-                int removed = 0;
-                for (Object classKey : cache.keySet()) {
-                    if (classKey == null) continue;
-
-                    Map<Long, CacheItem> class_cache = cache.get(classKey);
-                    for (Iterator<Map.Entry<Long, CacheItem>> it = class_cache.entrySet().iterator(); it.hasNext(); ) {
-                        Map.Entry<Long, CacheItem> entry = it.next();
-                        if (entry.getKey() == null) continue;
-                        // Check if session is still valid
-                        if (entry.getValue().bean.get() == null) {
-                            it.remove();
-                            removed++;
-                        }
-                    }
-                }
-                if (removed > 0)
-                    logger.info("DBBean GarbageCollector has cleared " + removed + " beans from cache.");
-            } catch (Exception e) {
-                logger.log(Level.SEVERE, "DBBeanGarbageCollector thread has crashed", e);
-            }
-        }
-    }
-
-
-
     public static boolean contains(DBBean obj) {
         if (obj == null)
             return false;
         return contains(obj.getClass(), obj.getId());
     }
+
     public static boolean contains(Class<?> c, Long id) {
         if (cache.containsKey(c)) {
             CacheItem cacheItem = cache.get(c).get(id);
+
             // Check if the cache is valid
             if (cacheItem != null && cacheItem.bean.get() != null) {
                 return true;
@@ -152,9 +92,11 @@ class DBBeanCache {
             cache.get(obj.getClass()).get(obj.getId()).updateTimestamp = System.currentTimeMillis();
             return;
         }
+
         CacheItem cacheItem = new CacheItem();
         cacheItem.updateTimestamp = System.currentTimeMillis();
         cacheItem.bean = new WeakReference<>(obj);
+
         if (cache.containsKey(obj.getClass()))
             cache.get(obj.getClass()).put(obj.getId(), cacheItem);
         else {