Java tutorial
/* * Licensed to the Apache Software Foundation (ASF) under one * or more contributor license agreements. See the NOTICE file * distributed with this work for additional information * regarding copyright ownership. The ASF licenses this file * to you 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 com.agimatec.validation.jsr303.xml; import com.agimatec.validation.jsr303.ConfigurationImpl; import com.agimatec.validation.jsr303.util.SecureActions; import com.agimatec.validation.util.PrivilegedActions; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.xml.sax.SAXException; import javax.validation.ConstraintValidatorFactory; import javax.validation.MessageInterpolator; import javax.validation.TraversableResolver; import javax.validation.ValidationException; import javax.validation.spi.ValidationProvider; import javax.xml.XMLConstants; import javax.xml.bind.JAXBContext; import javax.xml.bind.JAXBElement; import javax.xml.bind.JAXBException; import javax.xml.bind.Unmarshaller; import javax.xml.transform.stream.StreamSource; import javax.xml.validation.Schema; import javax.xml.validation.SchemaFactory; import java.io.IOException; import java.io.InputStream; import java.net.URL; import java.util.Enumeration; /** * Description: uses jaxb to parse validation.xml<br/> * User: roman <br/> * Date: 24.11.2009 <br/> * Time: 16:48:55 <br/> * Copyright: Agimatec GmbH */ public class ValidationParser { private static final String DEFAULT_VALIDATION_XML_FILE = "META-INF/validation.xml"; private static final String VALIDATION_CONFIGURATION_XSD = "META-INF/validation-configuration-1.0.xsd"; private static final Log log = LogFactory.getLog(ValidationParser.class); private final String validationXmlFile; public ValidationParser(String file) { if (file == null) { validationXmlFile = DEFAULT_VALIDATION_XML_FILE; } else { validationXmlFile = file; } } public void processValidationConfig(ConfigurationImpl targetConfig) { ValidationConfigType xmlConfig = parseXmlConfig(); if (xmlConfig != null) { applyConfig(xmlConfig, targetConfig); } } private ValidationConfigType parseXmlConfig() { try { InputStream inputStream = getInputStream(validationXmlFile); if (inputStream == null) { if (log.isDebugEnabled()) log.debug("No " + validationXmlFile + " found. Using annotation based configuration only."); return null; } if (log.isDebugEnabled()) log.debug(validationXmlFile + " found."); Schema schema = getSchema(); JAXBContext jc = JAXBContext.newInstance(ValidationConfigType.class); Unmarshaller unmarshaller = jc.createUnmarshaller(); unmarshaller.setSchema(schema); StreamSource stream = new StreamSource(inputStream); JAXBElement<ValidationConfigType> root = unmarshaller.unmarshal(stream, ValidationConfigType.class); return root.getValue(); } catch (JAXBException e) { throw new ValidationException("Unable to parse " + validationXmlFile, e); } catch (IOException e) { throw new ValidationException("Unable to parse " + validationXmlFile, e); } } private InputStream getInputStream(String path) throws IOException { ClassLoader loader = PrivilegedActions.getClassLoader(getClass()); Enumeration<URL> urls = loader.getResources(path); if (urls.hasMoreElements()) { URL url = urls.nextElement(); if (urls.hasMoreElements()) { // spec says: If more than one META-INF/validation.xml file // is found in the classpath, a ValidationException is raised. throw new ValidationException("More than one " + path + " is found in the classpath"); } return url.openStream(); } else { return null; } } private Schema getSchema() { return getSchema(VALIDATION_CONFIGURATION_XSD); } static Schema getSchema(String xsd) { ClassLoader loader = PrivilegedActions.getClassLoader(ValidationParser.class); SchemaFactory sf = SchemaFactory.newInstance(XMLConstants.W3C_XML_SCHEMA_NS_URI); URL schemaUrl = loader.getResource(xsd); try { return sf.newSchema(schemaUrl); } catch (SAXException e) { log.warn("Unable to parse schema: " + xsd, e); return null; } } private void applyConfig(ValidationConfigType xmlConfig, ConfigurationImpl targetConfig) { applyProviderClass(xmlConfig, targetConfig); applyMessageInterpolator(xmlConfig, targetConfig); applyTraversableResolver(xmlConfig, targetConfig); applyConstraintFactory(xmlConfig, targetConfig); applyMappingStreams(xmlConfig, targetConfig); applyProperties(xmlConfig, targetConfig); } private void applyProperties(ValidationConfigType xmlConfig, ConfigurationImpl target) { for (PropertyType property : xmlConfig.getProperty()) { if (log.isDebugEnabled()) { log.debug("Found property '" + property.getName() + "' with value '" + property.getValue() + "' in " + validationXmlFile); } target.addProperty(property.getName(), property.getValue()); } } private void applyProviderClass(ValidationConfigType xmlConfig, ConfigurationImpl target) { String providerClassName = xmlConfig.getDefaultProvider(); if (providerClassName != null) { Class<? extends ValidationProvider<?>> clazz = (Class<? extends ValidationProvider<?>>) SecureActions .loadClass(providerClassName, this.getClass()); target.setProviderClass(clazz); if (log.isInfoEnabled()) log.info("Using " + providerClassName + " as validation provider."); } } private void applyMessageInterpolator(ValidationConfigType xmlConfig, ConfigurationImpl target) { String messageInterpolatorClass = xmlConfig.getMessageInterpolator(); if (messageInterpolatorClass != null) { Class<MessageInterpolator> clazz = (Class<MessageInterpolator>) SecureActions .loadClass(messageInterpolatorClass, this.getClass()); target.messageInterpolator(SecureActions.newInstance(clazz)); if (log.isInfoEnabled()) log.info("Using " + messageInterpolatorClass + " as message interpolator."); } } private void applyTraversableResolver(ValidationConfigType xmlConfig, ConfigurationImpl target) { String traversableResolverClass = xmlConfig.getTraversableResolver(); if (traversableResolverClass != null) { Class<TraversableResolver> clazz = (Class<TraversableResolver>) SecureActions .loadClass(traversableResolverClass, this.getClass()); target.traversableResolver(SecureActions.newInstance(clazz)); if (log.isInfoEnabled()) log.info("Using " + traversableResolverClass + " as traversable resolver."); } } private void applyConstraintFactory(ValidationConfigType xmlConfig, ConfigurationImpl target) { String constraintFactoryClass = xmlConfig.getConstraintValidatorFactory(); if (constraintFactoryClass != null) { Class<ConstraintValidatorFactory> clazz = (Class<ConstraintValidatorFactory>) SecureActions .loadClass(constraintFactoryClass, this.getClass()); target.constraintValidatorFactory(SecureActions.newInstance(clazz)); if (log.isInfoEnabled()) log.info("Using " + constraintFactoryClass + " as constraint factory."); } } private void applyMappingStreams(ValidationConfigType xmlConfig, ConfigurationImpl target) { for (JAXBElement<String> mappingFileName : xmlConfig.getConstraintMapping()) { if (log.isDebugEnabled()) { log.debug("Trying to open input stream for " + mappingFileName.getValue()); } InputStream in; try { in = getInputStream(mappingFileName.getValue()); if (in == null) { throw new ValidationException( "Unable to open input stream for mapping file " + mappingFileName.getValue()); } } catch (IOException e) { throw new ValidationException( "Unable to open input stream for mapping file " + mappingFileName.getValue(), e); } target.addMapping(in); } } }