/*
* Copyright 2016 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.config.annotation;
import java.util.Map;
import java.util.concurrent.atomic.AtomicBoolean;
import org.springframework.beans.BeansException;
import org.springframework.beans.factory.BeanFactory;
import org.springframework.beans.factory.BeanFactoryAware;
import org.springframework.beans.factory.config.ConfigurableBeanFactory;
import org.springframework.beans.factory.support.AbstractBeanDefinition;
import org.springframework.beans.factory.support.BeanDefinitionBuilder;
import org.springframework.beans.factory.support.BeanDefinitionReaderUtils;
import org.springframework.beans.factory.support.BeanDefinitionRegistry;
import org.springframework.context.EnvironmentAware;
import org.springframework.context.annotation.ImportBeanDefinitionRegistrar;
import org.springframework.context.expression.BeanFactoryResolver;
import org.springframework.core.convert.ConversionService;
import org.springframework.core.env.Environment;
import org.springframework.core.type.AnnotationMetadata;
import org.springframework.data.gemfire.config.support.AutoRegionLookupBeanPostProcessor;
import org.springframework.expression.EvaluationException;
import org.springframework.expression.ExpressionParser;
import org.springframework.expression.ParseException;
import org.springframework.expression.spel.standard.SpelExpressionParser;
import org.springframework.expression.spel.support.StandardEvaluationContext;
import org.springframework.expression.spel.support.StandardTypeConverter;
import org.springframework.expression.spel.support.StandardTypeLocator;
import org.springframework.util.Assert;
import org.springframework.util.StringUtils;
/**
* The {@link AutoRegionLookupConfiguration} class is a Spring {@link ImportBeanDefinitionRegistrar} that enables
* the automatic lookup of GemFire Regions, which may have been defined else where, such as in {@literal cache.xml}
* or using GemFire's Cluster Configuration Service.
*
* This registrar works by registering the {@link AutoRegionLookupBeanPostProcessor} in the Spring application context,
* which is enabled when a Spring {@link org.springframework.context.annotation.Configuration @Configuration} annotated
* GemFire cache application class is annotated with {@link EnableAutoRegionLookup}.
*
* @author John Blum
* @see org.springframework.beans.factory.BeanFactory
* @see org.springframework.beans.factory.BeanFactoryAware
* @see org.springframework.context.EnvironmentAware
* @see org.springframework.context.annotation.ImportBeanDefinitionRegistrar
* @see org.springframework.core.env.Environment
* @see org.springframework.data.gemfire.config.annotation.EnableAutoRegionLookup
* @see org.springframework.data.gemfire.config.support.AutoRegionLookupBeanPostProcessor
* @since 1.9.0
*/
public class AutoRegionLookupConfiguration implements BeanFactoryAware, EnvironmentAware,
ImportBeanDefinitionRegistrar {
private static final AtomicBoolean AUTO_REGION_LOOKUP_BEAN_POST_PROCESSOR_REGISTERED = new AtomicBoolean(false);
private Environment environment;
private ExpressionParser spelParser = new SpelExpressionParser();
private StandardEvaluationContext evaluationContext = new StandardEvaluationContext();
/**
* {@inheritDoc}
*/
@Override
public void setBeanFactory(BeanFactory beanFactory) throws BeansException {
evaluationContext.setBeanResolver(new BeanFactoryResolver(beanFactory));
if (beanFactory instanceof ConfigurableBeanFactory) {
ConfigurableBeanFactory configurableBeanFactory = (ConfigurableBeanFactory) beanFactory;
evaluationContext.setTypeLocator(new StandardTypeLocator(configurableBeanFactory.getBeanClassLoader()));
ConversionService conversionService = configurableBeanFactory.getConversionService();
if (conversionService != null) {
evaluationContext.setTypeConverter(new StandardTypeConverter(conversionService));
}
}
}
/**
* {@inheritDoc}
*/
@Override
public void setEnvironment(Environment environment) {
this.environment = environment;
}
/**
* Returns a reference to the configured {@link Environment} in the Spring application context.
*
* @return a reference to the configured {@link Environment}.
* @throws IllegalStateException if the {@link Environment} reference was not properly configured.
* @see org.springframework.core.env.Environment
*/
protected Environment getEnvironment() {
Assert.state(environment != null, "The Environment was not properly configured");
return this.environment;
}
/**
* {@inheritDoc}
*/
@Override
public void registerBeanDefinitions(AnnotationMetadata importingClassMetadata, BeanDefinitionRegistry registry) {
Map<String, Object> enableAutoRegionLookupAttributes =
importingClassMetadata.getAnnotationAttributes(EnableAutoRegionLookup.class.getName());
String enabled = (String) enableAutoRegionLookupAttributes.get("enabled");
if (isEnabled(enabled)) {
registerAutoRegionLookupBeanPostProcessor(registry);
}
}
/* (non-Javadoc) */
private boolean isEnabled(String enabled) {
enabled = StringUtils.trimWhitespace(enabled);
if (!Boolean.parseBoolean(enabled)) {
try {
// try parsing as a SpEL expression...
return spelParser.parseExpression(enabled).getValue(evaluationContext, Boolean.TYPE);
}
catch (EvaluationException ignore) {
return false;
}
catch (ParseException ignore) {
// try resolving as a Spring property placeholder expression...
return getEnvironment().getProperty(enabled, Boolean.TYPE, false);
}
}
return true;
}
/* (non-Javadoc) */
private void registerAutoRegionLookupBeanPostProcessor(BeanDefinitionRegistry registry) {
if (AUTO_REGION_LOOKUP_BEAN_POST_PROCESSOR_REGISTERED.compareAndSet(false, true)) {
AbstractBeanDefinition autoRegionLookupBeanPostProcessor = BeanDefinitionBuilder
.rootBeanDefinition(AutoRegionLookupBeanPostProcessor.class)
.setRole(AbstractBeanDefinition.ROLE_INFRASTRUCTURE)
.getBeanDefinition();
BeanDefinitionReaderUtils.registerWithGeneratedName(autoRegionLookupBeanPostProcessor, registry);
}
}
}