org.activiti.spring.components.config.xml.StateHandlerAnnotationBeanFactoryPostProcessor.java Source code

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Here is the source code for org.activiti.spring.components.config.xml.StateHandlerAnnotationBeanFactoryPostProcessor.java

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/*
 * Copyright 2010 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.activiti.spring.components.config.xml;

import org.activiti.engine.ProcessEngine;
import org.activiti.spring.components.ActivitiContextUtils;
import org.activiti.spring.components.registry.ActivitiStateHandlerRegistry;
import org.springframework.beans.BeansException;
import org.springframework.beans.factory.config.BeanDefinition;
import org.springframework.beans.factory.config.BeanDefinitionHolder;
import org.springframework.beans.factory.config.BeanFactoryPostProcessor;
import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;
import org.springframework.beans.factory.support.BeanDefinitionReaderUtils;
import org.springframework.beans.factory.support.BeanDefinitionRegistry;
import org.springframework.beans.factory.support.RootBeanDefinition;

import java.util.logging.Logger;

/**
 * this class is responsible for registering the other {@link org.springframework.beans.factory.config.BeanFactoryPostProcessor}s
 * and {@link BeanFactoryPostProcessor}s.
 * <p/>
 * Particularly, this will register the {@link ActivitiStateHandlerRegistry} which is used to react to states.
 *
 * @author Josh Long
 */
public class StateHandlerAnnotationBeanFactoryPostProcessor implements BeanFactoryPostProcessor {

    private ProcessEngine processEngine;
    private Logger log = Logger.getLogger(getClass().getName());

    public void setProcessEngine(ProcessEngine processEngine) {
        this.processEngine = processEngine;
    }

    private void configureDefaultActivitiRegistry(String registryBeanName, BeanDefinitionRegistry registry) {

        if (!beanAlreadyConfigured(registry, registryBeanName, ActivitiStateHandlerRegistry.class)) {
            String registryName = ActivitiStateHandlerRegistry.class.getName();
            log.info("registering a " + registryName + " instance under bean name "
                    + ActivitiContextUtils.ACTIVITI_REGISTRY_BEAN_NAME + ".");

            RootBeanDefinition rootBeanDefinition = new RootBeanDefinition();
            rootBeanDefinition.setBeanClassName(registryName);
            rootBeanDefinition.getPropertyValues().addPropertyValue("processEngine", this.processEngine);

            BeanDefinitionHolder holder = new BeanDefinitionHolder(rootBeanDefinition, registryBeanName);
            BeanDefinitionReaderUtils.registerBeanDefinition(holder, registry);
        }
    }

    public void postProcessBeanFactory(ConfigurableListableBeanFactory beanFactory) throws BeansException {
        if (beanFactory instanceof BeanDefinitionRegistry) {
            BeanDefinitionRegistry registry = (BeanDefinitionRegistry) beanFactory;
            configureDefaultActivitiRegistry(ActivitiContextUtils.ACTIVITI_REGISTRY_BEAN_NAME, registry);

        } else {
            log.info("BeanFactory is not a BeanDefinitionRegistry. The default '"
                    + ActivitiContextUtils.ACTIVITI_REGISTRY_BEAN_NAME + "' cannot be configured.");
        }
    }

    private boolean beanAlreadyConfigured(BeanDefinitionRegistry registry, String beanName, Class clz) {
        if (registry.isBeanNameInUse(beanName)) {
            BeanDefinition bDef = registry.getBeanDefinition(beanName);
            if (bDef.getBeanClassName().equals(clz.getName())) {
                return true; // so the beans already registered, and of the right type. so we assume the user is overriding our configuration
            } else {
                throw new IllegalStateException("The bean name '" + beanName + "' is reserved.");
            }
        }
        return false;
    }
}