/*
* Copyright 2015 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.statemachine.support;
import org.springframework.beans.factory.BeanFactory;
import org.springframework.core.convert.ConversionService;
import org.springframework.core.task.TaskExecutor;
import org.springframework.expression.spel.support.StandardEvaluationContext;
import org.springframework.scheduling.TaskScheduler;
import org.springframework.statemachine.StateMachineSystemConstants;
import org.springframework.statemachine.event.StateMachineEventPublisher;
import org.springframework.util.Assert;
/**
* Utility methods for accessing common components from the BeanFactory.
*
* @author Janne Valkealahti
*
*/
public class StateMachineContextUtils {
/* Default task scheduler bean name */
public static final String TASK_SCHEDULER_BEAN_NAME = "taskScheduler";
/* Default task executor bean name */
public static final String TASK_EXECUTOR_BEAN_NAME = StateMachineSystemConstants.TASK_EXECUTOR_BEAN_NAME;
/* Default conversion service bean name */
public static final String CONVERSION_SERVICE_BEAN_NAME = "cloudClusterConversionService";
/* Default evaluation context bean name */
public static final String EVALUATION_CONTEXT_BEAN_NAME = "cloudClusterEvaluationContext";
/**
* Return the {@link TaskScheduler} bean whose name is "taskScheduler" if
* available.
*
* @param beanFactory BeanFactory for lookup, must not be null.
* @return task scheduler
*/
public static TaskScheduler getTaskScheduler(BeanFactory beanFactory) {
return getBeanOfType(beanFactory, TASK_SCHEDULER_BEAN_NAME, TaskScheduler.class);
}
/**
* Return the {@link TaskScheduler} bean whose name is "taskExecutor" if
* available.
*
* @param beanFactory BeanFactory for lookup, must not be null.
* @return task executor
*/
public static TaskExecutor getTaskExecutor(BeanFactory beanFactory) {
return getBeanOfType(beanFactory, TASK_EXECUTOR_BEAN_NAME, TaskExecutor.class);
}
/**
* Return the {@link ConversionService} bean whose name is
* "yarnConversionService" if available.
*
* @param beanFactory BeanFactory for lookup, must not be null.
*
* @return The {@link ConversionService} bean whose name is
* "yarnConversionService" if available.
*/
public static ConversionService getConversionService(BeanFactory beanFactory) {
return getBeanOfType(beanFactory, CONVERSION_SERVICE_BEAN_NAME, ConversionService.class);
}
/**
* Return the {@link StandardEvaluationContext} bean whose name is
* "yarnEvaluationContext" if available.
*
* @param beanFactory BeanFactory for lookup, must not be null.
*
* @return the instance of {@link StandardEvaluationContext} bean whose name
* is "yarnEvaluationContext" .
*/
public static StandardEvaluationContext getEvaluationContext(BeanFactory beanFactory) {
return getBeanOfType(beanFactory, EVALUATION_CONTEXT_BEAN_NAME, StandardEvaluationContext.class);
}
/**
* Return the {@link StateMachineEventPublisher} bean whose name is "stateMachineEventPublisher" if
* available.
*
* @param beanFactory BeanFactory for lookup, must not be null.
* @return state machine event publisher
*/
public static StateMachineEventPublisher getEventPublisher(BeanFactory beanFactory) {
return getBeanOfType(beanFactory, StateMachineSystemConstants.DEFAULT_ID_EVENT_PUBLISHER,
StateMachineEventPublisher.class);
}
/**
* Gets a bean from a factory with a given name and type.
*
* @param beanFactory the bean factory
* @param beanName the bean name
* @param type the type as of a class
* @return Bean known to a bean factory, null if not found.
*/
private static <T> T getBeanOfType(BeanFactory beanFactory, String beanName, Class<T> type) {
Assert.notNull(beanFactory, "BeanFactory must not be null");
if (!beanFactory.containsBean(beanName)) {
return null;
}
return beanFactory.getBean(beanName, type);
}
}