RepositoryConfigurationUtils.java

/*
 * Copyright 2014 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.repository.config;

import static org.springframework.beans.factory.support.BeanDefinitionReaderUtils.*;

import org.springframework.beans.factory.support.AbstractBeanDefinition;
import org.springframework.beans.factory.support.BeanDefinitionRegistry;
import org.springframework.beans.factory.support.RootBeanDefinition;
import org.springframework.util.Assert;

/**
 * Helper class to centralize common functionality that needs to be used in various places of the configuration
 * implementation.
 * 
 * @author Oliver Gierke
 */
public abstract class RepositoryConfigurationUtils {

	private RepositoryConfigurationUtils() {}

	/**
	 * Registeres the given {@link RepositoryConfigurationExtension} to indicate the repository configuration for a
	 * particular store (expressed through the extension's concrete type) has appened. Useful for downstream components
	 * that need to detect exactly that case. The bean definition is marked as lazy-init so that it doesn't get
	 * instantiated if no one really cares.
	 * 
	 * @param extension must not be {@literal null}.
	 * @param registry must not be {@literal null}.
	 * @param configurationSource must not be {@literal null}.
	 */
	public static void exposeRegistration(RepositoryConfigurationExtension extension, BeanDefinitionRegistry registry,
			RepositoryConfigurationSource configurationSource) {

		Assert.notNull(extension, "RepositoryConfigurationExtension must not be null!");
		Assert.notNull(registry, "BeanDefinitionRegistry must not be null!");
		Assert.notNull(configurationSource, "RepositoryConfigurationSource must not be null!");

		Class<? extends RepositoryConfigurationExtension> extensionType = extension.getClass();
		String beanName = extensionType.getName().concat(GENERATED_BEAN_NAME_SEPARATOR).concat("0");

		if (registry.containsBeanDefinition(beanName)) {
			return;
		}

		// Register extension as bean to indicate repository parsing and registration has happened
		RootBeanDefinition definition = new RootBeanDefinition(extensionType);
		definition.setSource(configurationSource.getSource());
		definition.setRole(AbstractBeanDefinition.ROLE_INFRASTRUCTURE);
		definition.setLazyInit(true);

		registry.registerBeanDefinition(beanName, definition);
	}
}