/* * Copyright 1999-2012 Alibaba Group. * * Licensed 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 com.alibaba.dubbo.rpc.cluster.merger; import com.alibaba.dubbo.common.extension.ExtensionLoader; import com.alibaba.dubbo.common.utils.ReflectUtils; import com.alibaba.dubbo.rpc.cluster.Merger; import java.util.Set; import java.util.concurrent.ConcurrentHashMap; import java.util.concurrent.ConcurrentMap; /** * @author <a href="mailto:gang.lvg@alibaba-inc.com">kimi</a> */ public class MergerFactory { private static final ConcurrentMap<Class<?>, Merger<?>> mergerCache = new ConcurrentHashMap<Class<?>, Merger<?>>(); public static <T> Merger<T> getMerger(Class<T> returnType) { Merger result; if (returnType.isArray()) { Class type = returnType.getComponentType(); result = mergerCache.get(type); if (result == null) { loadMergers(); result = mergerCache.get(type); } if(result == null && ! type.isPrimitive()) { result = ArrayMerger.INSTANCE; } } else { result = mergerCache.get(returnType); if (result == null) { loadMergers(); result = mergerCache.get(returnType); } } return result; } static void loadMergers() { Set<String> names = ExtensionLoader.getExtensionLoader(Merger.class) .getSupportedExtensions(); for (String name : names) { Merger m = ExtensionLoader.getExtensionLoader(Merger.class).getExtension(name); mergerCache.putIfAbsent(ReflectUtils.getGenericClass(m.getClass()), m); } } }