br.com.caelum.vraptor.ioc.spring.SpringBasedContainer.java Source code

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Here is the source code for br.com.caelum.vraptor.ioc.spring.SpringBasedContainer.java

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/***
 * Copyright (c) 2009 Caelum - www.caelum.com.br/opensource
 * All rights reserved.
 *
 * 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 br.com.caelum.vraptor.ioc.spring;

import java.util.Map;
import java.util.Set;
import java.util.Map.Entry;

import javax.servlet.ServletContext;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.BeansException;
import org.springframework.beans.factory.BeanFactoryUtils;
import org.springframework.beans.factory.DisposableBean;
import org.springframework.beans.factory.NoSuchBeanDefinitionException;
import org.springframework.beans.factory.config.BeanDefinition;
import org.springframework.beans.factory.config.BeanFactoryPostProcessor;
import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;
import org.springframework.beans.factory.support.AbstractBeanDefinition;
import org.springframework.web.context.ConfigurableWebApplicationContext;

import br.com.caelum.vraptor.ioc.AbstractComponentRegistry;
import br.com.caelum.vraptor.ioc.Container;

import com.google.common.collect.Sets;

/**
 * @author Fabio Kung
 */
public class SpringBasedContainer extends AbstractComponentRegistry implements Container {

    private static final class BeanRegistrationProcessor implements BeanFactoryPostProcessor {
        private final SpringBasedContainer container;

        public BeanRegistrationProcessor(SpringBasedContainer container) {
            this.container = container;
        }

        public void postProcessBeanFactory(ConfigurableListableBeanFactory factory) throws BeansException {
            SpringRegistry registry = new SpringRegistry(factory, container);

            registry.configure();

            registry.registerCustomComponents(container.toRegister);
        }

    }

    private static final Logger logger = LoggerFactory.getLogger(SpringBasedContainer.class);

    final Set<Class<?>> toRegister = Sets.newHashSet();

    private final ConfigurableWebApplicationContext parentContext;

    public SpringBasedContainer(ConfigurableWebApplicationContext parentContext) {
        this.parentContext = parentContext;
    }

    public void register(Class<?> requiredType, Class<?> componentType) {
        if (parentContext.isActive() && "VRaptor".equals(parentContext.getId())) {
            logger.info("registering class {} to {} after container initialization. Please avoid this",
                    requiredType, componentType);
            new SpringRegistry(parentContext.getBeanFactory(), this).register(componentType);
        } else {
            toRegister.add(componentType);
        }
    }

    public <T> T instanceFor(Class<T> type) {
        try {
            return parentContext.getBean(type);
        } catch (NoSuchBeanDefinitionException e) {
            Map<String, T> beans = parentContext.getBeansOfType(type);
            for (Entry<String, T> def : beans.entrySet()) {
                BeanDefinition definition = parentContext.getBeanFactory().getBeanDefinition(def.getKey());
                if (isPrimary(definition) || hasGreaterRoleThanInfrastructure(definition)) {
                    return def.getValue();
                }
            }
            throw e;
        }
    }

    public <T> boolean canProvide(Class<T> type) {
        return BeanFactoryUtils.beanNamesForTypeIncludingAncestors(parentContext, type).length > 0;
    }

    public void start(ServletContext context) {
        parentContext.setServletContext(context);
        parentContext.addBeanFactoryPostProcessor(new BeanRegistrationProcessor(this));
        parentContext.refresh();

        parentContext.start();
    }

    public void stop() {
        parentContext.stop();
        if (parentContext instanceof DisposableBean) {
            try {
                ((DisposableBean) parentContext).destroy();
            } catch (Exception e) {
                logger.error("Error when destroying application context", e);
            }
        }
    }

    private boolean isPrimary(BeanDefinition definition) {
        return definition instanceof AbstractBeanDefinition && ((AbstractBeanDefinition) definition).isPrimary();
    }

    private boolean hasGreaterRoleThanInfrastructure(BeanDefinition definition) {
        return definition.getRole() < BeanDefinition.ROLE_INFRASTRUCTURE;
    }
}