Java tutorial
/* * Copyright 2002-2013 the original author or authors. * * 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 org.springframework.data.gemfire.client; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.springframework.beans.BeansException; import org.springframework.beans.factory.config.BeanFactoryPostProcessor; import org.springframework.beans.factory.config.ConfigurableListableBeanFactory; import org.springframework.data.gemfire.function.execution.GemfireFunctionOperations; import org.springframework.data.gemfire.function.execution.GemfireOnServersFunctionTemplate; import org.springframework.data.gemfire.support.ListRegionsOnServerFunction; import org.springframework.util.Assert; import com.gemstone.gemfire.cache.Region; import com.gemstone.gemfire.cache.client.ClientCache; import com.gemstone.gemfire.cache.client.ClientRegionFactory; import com.gemstone.gemfire.cache.client.ClientRegionShortcut; /** * A {@link BeanFactoryPostProcessor} to register a Client Region bean, if necessary, for each Region accessible * to a Gemfire data source. If the Region is already defined, the definition will not be overridden. * * @author David Turanski * @author John Blum */ public class GemfireDataSourcePostProcessor implements BeanFactoryPostProcessor { private static Log logger = LogFactory.getLog(GemfireDataSourcePostProcessor.class); private final ClientCache cache; public GemfireDataSourcePostProcessor(final ClientCache cache) { this.cache = cache; } /* (non-Javadoc) * @see org.springframework.beans.factory.config.BeanFactoryPostProcessor#postProcessBeanFactory(org.springframework.beans.factory.config.ConfigurableListableBeanFactory) */ @Override public void postProcessBeanFactory(ConfigurableListableBeanFactory beanFactory) throws BeansException { createClientRegions(beanFactory); } private void createClientRegions(ConfigurableListableBeanFactory beanFactory) { GemfireFunctionOperations functionTemplate = new GemfireOnServersFunctionTemplate(cache); Iterable<String> regionNames = functionTemplate.executeAndExtract(new ListRegionsOnServerFunction()); ClientRegionFactory<?, ?> clientRegionFactory = null; if (regionNames != null && regionNames.iterator().hasNext()) { clientRegionFactory = cache.createClientRegionFactory(ClientRegionShortcut.PROXY); } for (String regionName : regionNames) { boolean createRegion = true; if (beanFactory.containsBean(regionName)) { Object existingBean = beanFactory.getBean(regionName); Assert.isTrue(existingBean instanceof Region, String.format( "Cannot create a ClientRegion bean named '%1$s'. A bean with this name of type '%2$s' already exists.", regionName, existingBean.getClass().getName())); createRegion = false; } if (createRegion) { if (logger.isDebugEnabled()) { logger.debug(String.format("Creating Client Region bean with name '%s'...", regionName)); } beanFactory.registerSingleton(regionName, clientRegionFactory.create(regionName)); } else { if (logger.isDebugEnabled()) { logger.debug(String.format("A Region named '%s' is already defined.", regionName)); } } } } }