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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.io.File; import java.io.FileFilter; 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.core.io.DefaultResourceLoader; import org.springframework.core.io.FileSystemResource; import org.springframework.core.io.Resource; import org.springframework.util.AntPathMatcher; import org.springframework.util.ClassUtils; import org.springframework.util.StringUtils; import org.springmodules.validation.bean.BeanValidator; import org.springmodules.validation.bean.conf.ValidationConfigurationException; import org.springmodules.validation.bean.conf.loader.xml.DefaultValidationRuleElementHandlerRegistry; import org.springmodules.validation.bean.conf.loader.xml.DefaultXmlBeanValidationConfigurationLoader; import org.springmodules.validation.bean.conf.loader.xml.handler.ClassValidationElementHandler; import org.springmodules.validation.bean.conf.loader.xml.handler.PropertyValidationElementHandler; import org.springmodules.validation.util.io.FileIterator; import org.springmodules.validation.util.xml.DomUtils; import org.springmodules.validation.util.xml.SubElementsIterator; import org.w3c.dom.Element; /** * @author Uri Boness */ public class XmlBasedValidatorBeanDefinitionParser extends AbstractBeanDefinitionParser implements ValidationBeansParserConstants { final static String ELEMENT_NAME = "xml-based-validator"; private final static String ERROR_CODE_CONVERTER_ATTR = "errorCodeConverter"; private final static String CLASS_ATTR = "class"; private final static String PATTERN_ATTR = "pattern"; private final static String DIR_ATTR = "dir"; private final static String LOCATION_ATTR = "location"; private final static String RESOURCE_ELEMENT = "resource"; private final static String RESOURCE_DIR_ELEMENT = "resource-dir"; private final static String ELEMENT_HANDLERS_ELEMENT = "element-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(DefaultValidationRuleElementHandlerRegistry.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); String loaderId = CONFIGURATION_LOADER_PREFIX + validatorId; BeanDefinitionBuilder loaderBuilder = BeanDefinitionBuilder .rootBeanDefinition(DefaultXmlBeanValidationConfigurationLoader.class); parseResourcesElements(element, loaderBuilder); loaderBuilder.addPropertyReference("elementHandlerRegistry", registryId); parserContext.getRegistry().registerBeanDefinition(loaderId, loaderBuilder.getBeanDefinition()); BeanDefinitionBuilder validatorBuilder = BeanDefinitionBuilder.rootBeanDefinition(BeanValidator.class); if (element.hasAttribute(ERROR_CODE_CONVERTER_ATTR)) { validatorBuilder.addPropertyReference("errorCodeConverter", element.getAttribute(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 parseResourcesElements(Element element, BeanDefinitionBuilder loaderBuilder) { List resources = new ArrayList(); for (Iterator subElements = new SubElementsIterator(element); subElements.hasNext();) { Element subElement = (Element) subElements.next(); if (subElement.getLocalName().equals(RESOURCE_ELEMENT)) { resources.add(createResource(subElement)); } else if (subElement.getLocalName().equals(RESOURCE_DIR_ELEMENT)) { resources.addAll(createResources(subElement)); } } loaderBuilder.addPropertyValue("resources", resources.toArray(new Resource[resources.size()])); } protected Resource createResource(Element resourceDefinition) { String path = resourceDefinition.getAttribute(LOCATION_ATTR); if (!StringUtils.hasText(path)) { throw new ValidationConfigurationException("Resoruce path is required and cannot be empty"); } return new DefaultResourceLoader().getResource(path); } protected List createResources(Element resourcesDefinition) { String dirName = resourcesDefinition.getAttribute(DIR_ATTR); final String pattern = resourcesDefinition.getAttribute(PATTERN_ATTR); final AntPathMatcher matcher = new AntPathMatcher(); FileFilter filter = new FileFilter() { public boolean accept(File file) { return matcher.match(pattern, file.getName()); } }; List resources = new ArrayList(); for (Iterator files = new FileIterator(dirName, filter); files.hasNext();) { File file = (File) files.next(); resources.add(new FileSystemResource(file)); } return resources; } protected void parseHandlerElements(Element element, BeanDefinitionBuilder registryBuilder) { Element functionsElement = DomUtils.getSingleSubElement(element, VALIDATION_BEANS_NAMESPACE, ELEMENT_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(CLASS_ATTR); Object handler = loadAndInstantiate(className); if (PropertyValidationElementHandler.class.isInstance(handler)) { propertyHandlers.add(handler); } else if (ClassValidationElementHandler.class.isInstance(handler)) { classHandlers.add(handler); } else { throw new ValidationConfigurationException( "class '" + className + "' is not a property hanlder nor a class handler"); } } registryBuilder.addPropertyValue("extraPropertyHandlers", propertyHandlers.toArray(new PropertyValidationElementHandler[propertyHandlers.size()])); registryBuilder.addPropertyValue("extraClassHandlers", classHandlers.toArray(new ClassValidationElementHandler[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); } } }