Github user meiercaleb commented on a diff in the pull request:
https://github.com/apache/incubator-rya/pull/251#discussion_r153589770
--- Diff:
extras/rya.pcj.fluo/pcj.fluo.app/src/main/java/org/apache/rya/indexing/pcj/fluo/app/query/MetadataCacheSupplier.java
---
@@ -0,0 +1,88 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied. See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+package org.apache.rya.indexing.pcj.fluo.app.query;
+
+import java.util.concurrent.locks.ReentrantLock;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public class MetadataCacheSupplier {
+
+ private static final Logger LOG =
LoggerFactory.getLogger(MetadataCacheSupplier.class);
+ private static FluoQueryMetadataCache CACHE;
+ private static boolean initialized = false;
+ private static final int DEFAULT_CAPACITY = 10000;
+ private static final int DEFAULT_CONCURRENCY = 8;
+ private static final ReentrantLock lock = new ReentrantLock();
+
+ /**
+ * Returns an existing cache with the specified instance name, or
creates a cache. The created cache will have the
+ * indicated capacity and concurrencyLevel if one is provided.
+ *
+ * @param capacity - capacity used to create a new cache
+ * @param concurrencyLevel - concurrencyLevel used to create a new
cache
+ */
+ public static FluoQueryMetadataCache getOrCreateCache(int capacity,
int concurrencyLevel) {
+ lock.lock();
+ try {
+ if (!initialized) {
+ LOG.debug("Cache has not been initialized. Initializing
cache with capacity: {} and concurrencylevel: {}", capacity,
+ concurrencyLevel);
+ CACHE = new FluoQueryMetadataCache(new
FluoQueryMetadataDAO(), capacity, concurrencyLevel);
+ initialized = true;
+ } else {
+ LOG.warn(
+ "A cache has already been initialized, so a cache
with capacity: {} and concurrency level: {} will not be created. Returning
existing cache with capacity: {} and concurrencylevel: {}",
+ capacity, concurrencyLevel, CACHE.getCapacity(),
CACHE.getConcurrencyLevel());
+ }
+ return CACHE;
+ } finally {
+ lock.unlock();
+ }
+ }
+
+ /**
+ * Returns cache with the name {@link
FluoQueryMetadataCache#FLUO_CACHE_INSTANCE} if it exists, otherwise creates it
--- End diff --
Updated.
---
