Java tutorial
/** * The contents of this file are subject to the OpenMRS Public License * Version 1.0 (the "License"); you may not use this file except in * compliance with the License. You may obtain a copy of the License at * http://license.openmrs.org * * Software distributed under the License is distributed on an "AS IS" * basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See the * License for the specific language governing rights and limitations * under the License. * * Copyright (C) OpenMRS, LLC. All Rights Reserved. */ package org.openmrs.contrib.metadatarepository.webapp.taglib; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.apache.commons.validator.Field; import org.apache.commons.validator.Form; import org.apache.commons.validator.ValidatorResources; import org.springframework.beans.factory.BeanFactoryUtils; import org.springframework.beans.factory.NoSuchBeanDefinitionException; import org.springframework.context.MessageSource; import org.springframework.context.NoSuchMessageException; import org.springframework.validation.Errors; import org.springframework.web.context.WebApplicationContext; import org.springframework.web.context.support.WebApplicationContextUtils; import org.springframework.web.servlet.DispatcherServlet; import org.springframework.web.servlet.support.RequestContext; import org.springmodules.validation.commons.ValidatorFactory; import javax.servlet.http.HttpServletRequest; import javax.servlet.jsp.JspException; import javax.servlet.jsp.tagext.TagSupport; import java.io.IOException; import java.util.List; import java.util.Locale; /** * <p>This class is designed to render a <label> tag for labeling your forms and * adds an asterik (*) for required fields. It was originally written by Erik * Hatcher (http://www.ehatchersolutions.com/JavaDevWithAnt/). * * <p>It is designed to be used as follows: * <pre><tag:label key="userForm.username"/></pre> * * @jsp.tag name="label" bodycontent="empty" */ public class LabelTag extends TagSupport { private static final long serialVersionUID = -5310144023136517119L; protected RequestContext requestContext; protected transient final Log log = LogFactory.getLog(LabelTag.class); protected String key = null; protected String styleClass = null; protected String errorClass = null; protected boolean colon = false; public int doStartTag() throws JspException { try { this.requestContext = new RequestContext((HttpServletRequest) this.pageContext.getRequest()); } catch (RuntimeException ex) { throw ex; } catch (Exception ex) { pageContext.getServletContext().log("Exception in custom tag", ex); } // Look up this key to see if its a field of the current form boolean requiredField = false; boolean validationError = false; ValidatorResources resources = getValidatorResources(); Locale locale = pageContext.getRequest().getLocale(); if (locale == null) { locale = Locale.getDefault(); } // get the name of the bean from the key String formName = key.substring(0, key.indexOf('.')); String fieldName = key.substring(formName.length() + 1); if (resources != null) { Form form = resources.getForm(locale, formName); if (form != null) { Field field = form.getField(fieldName); if (field != null) { if (field.isDependency("required") || field.isDependency("validwhen")) { requiredField = true; } } } } Errors errors = requestContext.getErrors(formName, false); List fes = null; if (errors != null) { fes = errors.getFieldErrors(fieldName); //String errorMsg = getErrorMessages(fes); } if (fes != null && fes.size() > 0) { validationError = true; } // Retrieve the message string we are looking for String message = null; try { message = getMessageSource().getMessage(key, null, locale); } catch (NoSuchMessageException nsm) { message = "???" + key + "???"; } String cssClass = null; if (styleClass != null) { cssClass = styleClass; } else if (requiredField) { cssClass = "required"; } String cssErrorClass = (errorClass != null) ? errorClass : "error"; StringBuffer label = new StringBuffer(); if ((message == null) || "".equals(message.trim())) { label.append(""); } else { label.append("<label for=\"").append(fieldName).append("\""); if (validationError) { label.append(" class=\"").append(cssErrorClass).append("\""); } else if (cssClass != null) { label.append(" class=\"").append(cssClass).append("\""); } label.append(">").append(message); label.append((requiredField) ? " <span class=\"req\">*</span>" : ""); label.append((colon) ? ":" : ""); label.append("</label>"); if (validationError) { label.append("<img class=\"validationWarning\" alt=\""); label.append(getMessageSource().getMessage("icon.warning", null, locale)); label.append("\""); String context = ((HttpServletRequest) pageContext.getRequest()).getContextPath(); label.append(" src=\"").append(context); label.append(getMessageSource().getMessage("icon.warning.img", null, locale)); label.append("\" />"); } } // Print the retrieved message to our output writer try { writeMessage(label.toString()); } catch (IOException io) { io.printStackTrace(); throw new JspException("Error writing label: " + io.getMessage()); } // Continue processing this page return (SKIP_BODY); } /** * Extract the error messages from the given ObjectError list. */ /*private String getErrorMessages(List fes) throws NoSuchMessageException { StringBuffer message = new StringBuffer(); for (int i = 0; i < fes.size(); i++) { ObjectError error = (ObjectError) fes.get(i); message.append(this.requestContext.getMessage(error, true)); } return message.toString(); }*/ /** * Write the message to the page. * @param msg the message to write * @throws IOException if writing failed */ protected void writeMessage(String msg) throws IOException { pageContext.getOut().write(msg); } /** * @jsp.attribute required="true" rtexprvalue="true" */ public void setKey(String key) { this.key = key; } /** * Setter for specifying whether to include colon * @jsp.attribute required="false" rtexprvalue="true" */ public void setColon(boolean colon) { this.colon = colon; } /** * Setter for assigning a CSS class, default is label. * * @jsp.attribute required="false" rtexprvalue="true" */ public void setStyleClass(String styleClass) { this.styleClass = styleClass; } /** * Setter for assigning a CSS class when errors occur, * defaults to labelError. * * @jsp.attribute required="false" rtexprvalue="true" */ public void setErrorClass(String errorClass) { this.errorClass = errorClass; } /** * Release all allocated resources. */ public void release() { super.release(); key = null; colon = false; styleClass = null; errorClass = null; } /** * Get the validator resources from a ValidatorFactory defined in the * web application context or one of its parent contexts. * The bean is resolved by type (org.springframework.validation.commons.ValidatorFactory). * * @return ValidatorResources from a ValidatorFactory. */ private ValidatorResources getValidatorResources() { // look in servlet beans definition (i.e. action-servlet.xml) WebApplicationContext ctx = (WebApplicationContext) pageContext.getRequest() .getAttribute(DispatcherServlet.WEB_APPLICATION_CONTEXT_ATTRIBUTE); ValidatorFactory factory = null; try { factory = (ValidatorFactory) BeanFactoryUtils.beanOfTypeIncludingAncestors(ctx, ValidatorFactory.class, true, true); } catch (NoSuchBeanDefinitionException e) { // look in main application context (i.e. applicationContext.xml) ctx = WebApplicationContextUtils.getRequiredWebApplicationContext(pageContext.getServletContext()); factory = (ValidatorFactory) BeanFactoryUtils.beanOfTypeIncludingAncestors(ctx, ValidatorFactory.class, true, true); } return factory.getValidatorResources(); } /** * Use the application context itself for default message resolution. */ private MessageSource getMessageSource() { return requestContext.getWebApplicationContext(); } }