| /* |
| * 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.geode.cache.query.internal.cq; |
| |
| import java.io.DataInput; |
| import java.io.IOException; |
| import java.util.Iterator; |
| import java.util.ServiceLoader; |
| |
| import org.apache.geode.annotations.Immutable; |
| import org.apache.geode.annotations.internal.MutableForTesting; |
| import org.apache.geode.cache.query.internal.cq.spi.CqServiceFactory; |
| import org.apache.geode.internal.cache.InternalCache; |
| import org.apache.geode.util.internal.GeodeGlossary; |
| |
| public class CqServiceProvider { |
| |
| @Immutable |
| private static final CqServiceFactory factory; |
| |
| /** |
| * System property to maintain the CQ event references for optimizing the updates. This will allow |
| * running the CQ query only once during update events. |
| */ |
| @MutableForTesting |
| public static boolean MAINTAIN_KEYS = Boolean |
| .parseBoolean(System.getProperty(GeodeGlossary.GEMFIRE_PREFIX + "cq.MAINTAIN_KEYS", "true")); |
| |
| /** |
| * A debug flag used for testing vMotion during CQ registration |
| */ |
| public static final boolean VMOTION_DURING_CQ_REGISTRATION_FLAG = false; |
| |
| static { |
| ServiceLoader<CqServiceFactory> loader = ServiceLoader.load(CqServiceFactory.class); |
| Iterator<CqServiceFactory> itr = loader.iterator(); |
| if (!itr.hasNext()) { |
| factory = null; |
| } else { |
| factory = itr.next(); |
| factory.initialize(); |
| } |
| } |
| |
| public static CqService create(InternalCache cache) { |
| if (factory == null) { |
| return new MissingCqService(); |
| } |
| |
| return factory.create(cache); |
| } |
| |
| public static ServerCQ readCq(DataInput in) throws ClassNotFoundException, IOException { |
| if (factory == null) { |
| throw new IllegalStateException("CqService is not available."); |
| } else { |
| return factory.readCqQuery(in); |
| } |
| } |
| |
| private CqServiceProvider() {} |
| } |