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/* * $Id: ValidatorPlugIn.java 483039 2006-12-06 11:34:28Z niallp $ * * 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 org.apache.struts.validator; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.apache.commons.validator.ValidatorResources; import org.apache.struts.action.ActionServlet; import org.apache.struts.action.PlugIn; import org.apache.struts.config.ModuleConfig; import org.xml.sax.SAXException; import javax.servlet.ServletException; import javax.servlet.UnavailableException; import java.io.IOException; import java.net.URL; import java.util.ArrayList; import java.util.List; import java.util.StringTokenizer; /** * Loads <code>ValidatorResources</code> based on configuration in the * struts-config.xml file. * * @version $Rev: 483039 $ $Date: 2005-08-30 00:22:27 -0400 (Tue, 30 Aug 2005) * $ * @since Struts 1.1 */ public class ValidatorPlugIn implements PlugIn { /** * Commons Logging instance. */ private static Log log = LogFactory.getLog(ValidatorPlugIn.class); /** * Delimitter for Validator resources. */ private final static String RESOURCE_DELIM = ","; /** * Application scope key that <code>ValidatorResources</code> is stored * under. */ public final static String VALIDATOR_KEY = "org.apache.commons.validator.VALIDATOR_RESOURCES"; /** * Application scope key that <code>StopOnError</code> is stored under. * * @since Struts 1.2 */ public final static String STOP_ON_ERROR_KEY = "org.apache.struts.validator.STOP_ON_ERROR"; /** * The module configuration for our owning module. */ private ModuleConfig config = null; /** * The {@link ActionServlet} owning this application. */ private ActionServlet servlet = null; /** * The set of Form instances that have been created and initialized, keyed * by the struts form name. */ protected ValidatorResources resources = null; // ------------------------------------------------------------- Properties /** * A comma delimitted list of Validator resource. */ private String pathnames = null; /** * Informs the Validators if it has to stop validation when finding the * first error or if it should continue. Default to <code>true</code> to * keep Struts 1.1 backwards compatibility. */ private boolean stopOnFirstError = true; /** * Gets a comma delimitted list of Validator resources. * * @return comma delimited list of Validator resource path names */ public String getPathnames() { return pathnames; } /** * Sets a comma delimitted list of Validator resources. * * @param pathnames delimited list of Validator resource path names */ public void setPathnames(String pathnames) { this.pathnames = pathnames; } /** * Gets the value for stopOnFirstError. * * @return A boolean indicating whether JavaScript validation should stop * when it finds the first error (Struts 1.1 behaviour) or * continue validation. * @since Struts 1.2 */ public boolean isStopOnFirstError() { return this.stopOnFirstError; } /** * Sets the value for stopOnFirstError. * * @param stopOnFirstError A boolean indicating whether JavaScript * validation should stop when it finds the first * error (Struts 1.1 behaviour) or continue * validation. * @since Struts 1.2 */ public void setStopOnFirstError(boolean stopOnFirstError) { this.stopOnFirstError = stopOnFirstError; } /** * Initialize and load our resources. * * @param servlet The ActionServlet for our application * @param config The ModuleConfig for our owning module * @throws ServletException if we cannot configure ourselves correctly */ public void init(ActionServlet servlet, ModuleConfig config) throws ServletException { // Remember our associated configuration and servlet this.config = config; this.servlet = servlet; // Load our database from persistent storage try { this.initResources(); servlet.getServletContext().setAttribute(VALIDATOR_KEY + config.getPrefix(), resources); servlet.getServletContext().setAttribute(STOP_ON_ERROR_KEY + '.' + config.getPrefix(), (this.stopOnFirstError ? Boolean.TRUE : Boolean.FALSE)); } catch (Exception e) { log.error(e.getMessage(), e); throw new UnavailableException("Cannot load a validator resource from '" + pathnames + "'"); } } /** * Gracefully shut down, releasing any resources that were allocated at * initialization. */ public void destroy() { if (log.isDebugEnabled()) { log.debug("Destroying ValidatorPlugin"); } servlet = null; config = null; destroyResources(); } /** * Initialize the validator resources for this module. * * @throws IOException if an input/output error is encountered * @throws ServletException if we cannot initialize these resources */ protected void initResources() throws IOException, ServletException { if ((pathnames == null) || (pathnames.length() <= 0)) { return; } StringTokenizer st = new StringTokenizer(pathnames, RESOURCE_DELIM); List urlList = new ArrayList(); try { while (st.hasMoreTokens()) { String validatorRules = st.nextToken().trim(); if (log.isInfoEnabled()) { log.info("Loading validation rules file from '" + validatorRules + "'"); } URL input = servlet.getServletContext().getResource(validatorRules); // If the config isn't in the servlet context, try the class // loader which allows the config files to be stored in a jar if (input == null) { input = getClass().getResource(validatorRules); } if (input != null) { urlList.add(input); } else { throw new ServletException("Skipping validation rules file from '" + validatorRules + "'. No url could be located."); } } int urlSize = urlList.size(); URL[] urlArray = new URL[urlSize]; for (int urlIndex = 0; urlIndex < urlSize; urlIndex++) { urlArray[urlIndex] = (URL) urlList.get(urlIndex); } this.resources = new ValidatorResources(urlArray); } catch (SAXException sex) { log.error("Skipping all validation", sex); throw new ServletException(sex); } } /** * Destroy <code>ValidatorResources</code>. */ protected void destroyResources() { resources = null; } }