#1427 - QueryCache should be cleared, if one of a dependent bean is updated

Initial work, does not include propagation across cluster.

src/main/java/io/ebeaninternal/server/cache/DefaultServerQueryCache.java

@@ -0,0 +1,41 @@
+package io.ebeaninternal.server.cache;
+
+import io.ebean.cache.QueryCacheEntry;
+import io.ebean.cache.QueryCacheEntryValidate;
+
+/**
+ * Server cache for query caching.
+ * <p>
+ * Entries in this cache contain QueryCacheEntry and we need to additionally
+ * validate the entries when hit for changes to dependent tables.
+ * </p>
+ */
+public class DefaultServerQueryCache extends DefaultServerCache {
+
+  private final QueryCacheEntryValidate queryCacheEntryValidate;
+
+  public DefaultServerQueryCache(DefaultServerCacheConfig config) {
+    super(config);
+    this.queryCacheEntryValidate = config.getQueryCacheEntryValidate();
+  }
+
+  protected Object unwrapEntry(CacheEntry entry) {
+    return ((QueryCacheEntry) entry.getValue()).getValue();
+  }
+
+  @Override
+  protected CacheEntry getCacheEntry(Object id) {
+    Object key = key(id);
+    CacheEntry entry = map.get(key);
+    if (entry == null) {
+      return null;
+    }
+    QueryCacheEntry value = (QueryCacheEntry) entry.getValue();
+    if (!queryCacheEntryValidate.isValid(value)) {
+      map.remove(key);
+      removeCount.increment();
+      return null;
+    }
+    return entry;
+  }
+}