Java tutorial
/** * 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.nutch.webui.client; import java.util.concurrent.ExecutionException; import org.apache.nutch.webui.client.impl.NutchClientImpl; import org.apache.nutch.webui.model.NutchInstance; import org.springframework.stereotype.Component; import com.google.common.cache.CacheBuilder; import com.google.common.cache.CacheLoader; import com.google.common.cache.LoadingCache; @Component public class NutchClientFactory { private LoadingCache<NutchInstance, NutchClient> cache; public NutchClientFactory() { cache = CacheBuilder.newBuilder().build(new NutchClientCacheLoader()); } public NutchClient getClient(NutchInstance instance) { try { return cache.get(instance); } catch (ExecutionException e) { throw new IllegalStateException(e); } } private static class NutchClientCacheLoader extends CacheLoader<NutchInstance, NutchClient> { @Override public NutchClient load(NutchInstance key) throws Exception { return new NutchClientImpl(key); } } }