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/* * Copyright 2004-2005 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.springmodules.validation.bean.conf.namespace; import java.util.ArrayList; import java.util.Iterator; import java.util.List; import org.springframework.beans.factory.support.AbstractBeanDefinition; import org.springframework.beans.factory.support.BeanDefinitionBuilder; import org.springframework.beans.factory.xml.AbstractBeanDefinitionParser; import org.springframework.beans.factory.xml.ParserContext; import org.springframework.util.ClassUtils; import org.springmodules.validation.bean.BeanValidator; import org.springmodules.validation.bean.conf.ValidationConfigurationException; import org.springmodules.validation.bean.conf.loader.annotation.AnnotationBeanValidationConfigurationLoader; import org.springmodules.validation.bean.conf.loader.annotation.DefaultValidationAnnotationHandlerRegistry; import org.springmodules.validation.bean.conf.loader.annotation.handler.ClassValidationAnnotationHandler; import org.springmodules.validation.bean.conf.loader.annotation.handler.PropertyValidationAnnotationHandler; import org.springmodules.validation.bean.conf.loader.annotation.handler.ValidationAnnotationHandlersBundle; import org.springmodules.validation.util.xml.DomUtils; import org.springmodules.validation.util.xml.SubElementsIterator; import org.w3c.dom.Element; /** * @author Uri Boness */ public class AnnotationBasedValidatorBeanDefinitionParser extends AbstractBeanDefinitionParser implements ValidationBeansParserConstants { final static String ELEMENT_NAME = "annotation-based-validator"; private final static String ERROR_CODE_CONVERTER_ATTR = "errorCodeConverter"; private final static String CLASS_ATTR = "class"; private final static String ANNOTATION_HANDLERS_ELEMENT = "annotation-handlers"; private final static String HANDLER_ELEMENT = "handler"; private static final String HANDLER_REGISTRY_PREFIX = "__handler_registry_"; private static final String CONFIGURATION_LOADER_PREFIX = "__configuration_loader_"; protected AbstractBeanDefinition parseInternal(Element element, ParserContext parserContext) { BeanDefinitionBuilder registryBuilder = BeanDefinitionBuilder .rootBeanDefinition(DefaultValidationAnnotationHandlerRegistry.class); parseHandlerElements(element, registryBuilder); AbstractBeanDefinition beanDefinition = registryBuilder.getBeanDefinition(); String validatorId = resolveId(element, beanDefinition, parserContext); String registryId = HANDLER_REGISTRY_PREFIX + validatorId; parserContext.getRegistry().registerBeanDefinition(registryId, beanDefinition); BeanDefinitionBuilder loaderBuilder = BeanDefinitionBuilder .rootBeanDefinition(AnnotationBeanValidationConfigurationLoader.class); loaderBuilder.addPropertyReference("handlerRegistry", registryId); beanDefinition = loaderBuilder.getBeanDefinition(); String loaderId = CONFIGURATION_LOADER_PREFIX + validatorId; parserContext.getRegistry().registerBeanDefinition(loaderId, beanDefinition); BeanDefinitionBuilder validatorBuilder = BeanDefinitionBuilder.rootBeanDefinition(BeanValidator.class); if (element.hasAttribute(AnnotationBasedValidatorBeanDefinitionParser.ERROR_CODE_CONVERTER_ATTR)) { validatorBuilder.addPropertyReference("errorCodeConverter", element.getAttribute(AnnotationBasedValidatorBeanDefinitionParser.ERROR_CODE_CONVERTER_ATTR)); } validatorBuilder.addPropertyReference("configurationLoader", loaderId); return validatorBuilder.getBeanDefinition(); } /** * Returns the {@link org.springmodules.validation.bean.BeanValidator} class. * * @see org.springframework.beans.factory.xml.AbstractSingleBeanDefinitionParser#doParse(org.w3c.dom.Element, org.springframework.beans.factory.support.BeanDefinitionBuilder) */ protected Class getBeanClass(Element element) { return BeanValidator.class; } //=============================================== Helper Methods =================================================== protected void parseHandlerElements(Element element, BeanDefinitionBuilder registryBuilder) { Element functionsElement = DomUtils.getSingleSubElement(element, VALIDATION_BEANS_NAMESPACE, ANNOTATION_HANDLERS_ELEMENT); if (functionsElement == null) { return; } Iterator handlerElements = new SubElementsIterator(functionsElement, VALIDATION_BEANS_NAMESPACE, HANDLER_ELEMENT); List propertyHandlers = new ArrayList(); List classHandlers = new ArrayList(); while (handlerElements.hasNext()) { Element handlerElement = (Element) handlerElements.next(); String className = handlerElement.getAttribute(AnnotationBasedValidatorBeanDefinitionParser.CLASS_ATTR); Object handler = loadAndInstantiate(className); if (PropertyValidationAnnotationHandler.class.isInstance(handler)) { propertyHandlers.add(handler); } else if (ClassValidationAnnotationHandler.class.isInstance(handler)) { classHandlers.add(handler); } else if (ValidationAnnotationHandlersBundle.class.isInstance(handler)) { ValidationAnnotationHandlersBundle source = (ValidationAnnotationHandlersBundle) handler; propertyHandlers.addAll(source.getPropertyHandlers()); classHandlers.addAll(source.getClassHandlers()); } else { throw new ValidationConfigurationException( "class '" + className + "' is not a property hanlder nor a class handler"); } } registryBuilder.addPropertyValue("extraPropertyHandlers", propertyHandlers.toArray(new PropertyValidationAnnotationHandler[propertyHandlers.size()])); registryBuilder.addPropertyValue("extraClassHandlers", classHandlers.toArray(new ClassValidationAnnotationHandler[classHandlers.size()])); } //=============================================== Helper Methods =================================================== /** * Loads and instantiates the given class. * * @param className The name of the given class. */ protected Object loadAndInstantiate(String className) { Class clazz; try { clazz = ClassUtils.forName(className); return clazz.newInstance(); } catch (ClassNotFoundException cnfe) { throw new ValidationConfigurationException("Could not load class '" + className + "'", cnfe); } catch (IllegalAccessException iae) { throw new ValidationConfigurationException("Could not instantiate class '" + className + "'", iae); } catch (InstantiationException ie) { throw new ValidationConfigurationException("Could not instantiate class '" + className + "'", ie); } } }