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 com.twitter.distributedlog.service.config; import com.google.common.base.Optional; import com.google.common.collect.Lists; import com.twitter.distributedlog.DistributedLogConfiguration; import com.twitter.distributedlog.config.ConcurrentConstConfiguration; import com.twitter.distributedlog.config.ConfigurationSubscription; import com.twitter.distributedlog.config.DynamicDistributedLogConfiguration; import com.twitter.distributedlog.config.FileConfigurationBuilder; import com.twitter.distributedlog.config.PropertiesConfigurationBuilder; import org.apache.commons.configuration.ConfigurationException; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import java.io.File; import java.net.MalformedURLException; import java.util.List; import java.util.concurrent.ScheduledExecutorService; import java.util.concurrent.TimeUnit; /** * For all streams return the same dynamic config based on configFile. */ public class DefaultStreamConfigProvider implements StreamConfigProvider { static final Logger LOG = LoggerFactory.getLogger(DefaultStreamConfigProvider.class); private final Optional<DynamicDistributedLogConfiguration> dynConf; private final ConfigurationSubscription confSub; public DefaultStreamConfigProvider(String configFilePath, ScheduledExecutorService executorService, int reloadPeriod, TimeUnit reloadUnit) throws ConfigurationException { try { File configFile = new File(configFilePath); FileConfigurationBuilder properties = new PropertiesConfigurationBuilder(configFile.toURI().toURL()); ConcurrentConstConfiguration defaultConf = new ConcurrentConstConfiguration( new DistributedLogConfiguration()); DynamicDistributedLogConfiguration conf = new DynamicDistributedLogConfiguration(defaultConf); List<FileConfigurationBuilder> fileConfigBuilders = Lists.newArrayList(properties); confSub = new ConfigurationSubscription(conf, fileConfigBuilders, executorService, reloadPeriod, reloadUnit); this.dynConf = Optional.of(conf); } catch (MalformedURLException ex) { throw new ConfigurationException(ex); } } @Override public Optional<DynamicDistributedLogConfiguration> getDynamicStreamConfig(String streamName) { return dynConf; } }