Java tutorial
/** * Copyright 2005-2014 The Kuali Foundation * * Licensed under the Educational Community 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.opensource.org/licenses/ecl2.php * * 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.kuali.rice.edl.impl.components; import java.util.ArrayList; import java.util.List; import java.util.Map; import javax.xml.xpath.XPath; import javax.xml.xpath.XPathConstants; import org.apache.commons.lang.StringUtils; import org.kuali.rice.edl.impl.EDLContext; import org.kuali.rice.edl.impl.EDLModelComponent; import org.kuali.rice.edl.impl.EDLXmlUtils; import org.kuali.rice.edl.impl.RequestParser; import org.kuali.rice.edl.impl.service.EdlServiceLocator; import org.kuali.rice.kew.api.WorkflowRuntimeException; import org.kuali.rice.kew.rule.xmlrouting.XPathHelper; import org.w3c.dom.Document; import org.w3c.dom.Element; import org.w3c.dom.NodeList; /** * Executes validations that are defined on the EDL Definitions. These validation exist in a form * similiar to the following: * * <validations> * <validation type="xpath"> * <expression>wf:field('grade') = 'other' and not(wf:empty(wf:field('otherGrade'))</expression> * <message>Other Grade is required when grade is marked as 'other'</message> * </validation> * </validations> * * @author Kuali Rice Team (rice.collab@kuali.org) */ public class ValidationComponent extends SimpleWorkflowEDLConfigComponent implements EDLModelComponent { private static final String XPATH_TYPE = "xpath"; private EDLContext edlContext; public void updateDOM(Document dom, Element configElement, EDLContext edlContext) { if (edlContext.getUserAction().isValidatableAction()) { try { Document edlDef = EdlServiceLocator.getEDocLiteService() .getDefinitionXml(edlContext.getEdocLiteAssociation()); List<EDLValidation> validations = parseValidations(edlDef); if (!validations.isEmpty()) { XPath xpath = XPathHelper.newXPath(dom); for (EDLValidation validation : validations) { executeValidation(xpath, dom, validation, edlContext); } } } catch (Exception e) { if (e instanceof RuntimeException) { throw (RuntimeException) e; } throw new WorkflowRuntimeException("Failed to execute EDL validations.", e); } } } protected List<EDLValidation> parseValidations(Document document) throws Exception { List<EDLValidation> validations = new ArrayList<EDLValidation>(); XPath xpath = XPathHelper.newXPath(document); NodeList validationNodes = (NodeList) xpath.evaluate("/edl/validations/validation", document, XPathConstants.NODESET); for (int index = 0; index < validationNodes.getLength(); index++) { Element validationElem = (Element) validationNodes.item(index); EDLValidation validation = new EDLValidation(); String type = validationElem.getAttribute("type"); String key = validationElem.getAttribute("key"); String expression = EDLXmlUtils.getChildElementTextValue(validationElem, "expression"); String message = EDLXmlUtils.getChildElementTextValue(validationElem, "message"); if (StringUtils.isBlank(type)) { throw new WorkflowRuntimeException( "An improperly configured validation was found with an empty type."); } if (StringUtils.isBlank(expression)) { throw new WorkflowRuntimeException( "An improperly configured validation was found with an empty expression."); } if (StringUtils.isBlank(message)) { throw new WorkflowRuntimeException( "An improperly configured validation was found with an empty message."); } validation.setType(type); validation.setKey(key); validation.setExpression(expression); validation.setMessage(message); validations.add(validation); } return validations; } protected void executeValidation(XPath xpath, Document dom, EDLValidation validation, EDLContext edlContext) throws Exception { // TODO: in the future, allow this to be pluggable, hardcode for now if (XPATH_TYPE.equals(validation.getType())) { Boolean result = (Boolean) xpath.evaluate(validation.getExpression(), dom, XPathConstants.BOOLEAN); // if validation returns false, we'll flag the error if (!result) { String key = validation.getKey(); if (!StringUtils.isEmpty(key)) { Map<String, String> fieldErrors = (Map<String, String>) edlContext.getRequestParser() .getAttribute(RequestParser.GLOBAL_FIELD_ERRORS_KEY); fieldErrors.put(key, validation.getMessage()); // set invalid attribute to true on corresponding field //TODO remove - handled this in the widgets // Element edlElement = EDLXmlUtils.getEDLContent(dom, false); // Element edlSubElement = EDLXmlUtils.getOrCreateChildElement(edlElement, "data", true); // NodeList versionNodes = edlSubElement.getChildNodes(); // for (int i = 0; i < versionNodes.getLength(); i++) { // Element version = (Element) versionNodes.item(i); // String current = version.getAttribute("current"); // if (current == "true") { // NodeList fieldNodes = version.getChildNodes(); // for (int j = 0; j < fieldNodes.getLength(); j++) { // Element field = (Element) fieldNodes.item(j); // String fieldName = field.getAttribute("name"); // if(fieldName.equals(key)) { // field.setAttribute("invalid", "true"); // break; // } // } // } // } } else { List globalErrors = (List) edlContext.getRequestParser() .getAttribute(RequestParser.GLOBAL_ERRORS_KEY); globalErrors.add(validation.getMessage()); } edlContext.setInError(true); } } else { throw new WorkflowRuntimeException( "Illegal validation type specified. Only 'xpath' is currently supported."); } } }