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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.commons.taglib; import java.io.IOException; import java.util.*; import javax.servlet.http.HttpServletRequest; import javax.servlet.jsp.JspException; import javax.servlet.jsp.JspWriter; import javax.servlet.jsp.tagext.BodyTagSupport; import org.apache.commons.validator.*; import org.apache.commons.validator.util.ValidatorUtils; import org.springframework.beans.factory.BeanFactoryUtils; import org.springframework.context.MessageSource; 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.springframework.web.servlet.support.RequestContextUtils; import org.springmodules.validation.commons.MessageUtils; import org.springmodules.validation.commons.ValidatorFactory; /** * Custom tag that generates JavaScript for client side validation based * on the validation rules loaded by a <code>ValidatorFactory</code>. * <p/> * <p>The validator resources needed for this tag are retrieved from a * ValidatorFactory bean defined in the web application context or one * of its parent contexts. The bean is resolved by type * (<code>org.springmodules.commons.validator.ValidatorFactory</code>).</p> * * @author David Winterfeldt. * @author Daniel Miller */ public class JavascriptValidatorTag extends BodyTagSupport { protected RequestContext requestContext; /** * The name of the form that corresponds with the action name * in struts-config.xml. Specifying a form name places a * <script> </script> around the javascript. */ protected String formName = null; /** * The line ending string. */ protected static String lineEnd = System.getProperty("line.separator"); /** * The current page number of a multi-part form. * Only valid when the formName attribute is set. */ protected int page = 0; /** * This will be used as is for the JavaScript validation method name if it has a value. This is * the method name of the main JavaScript method that the form calls to perform validations. */ protected String methodName = null; /** * The static JavaScript methods will only be printed if this is set to "true". */ protected String staticJavascript = "true"; /** * The dynamic JavaScript objects will only be generated if this is set to "true". */ protected String dynamicJavascript = "true"; /** * The src attribute for html script element (used to include an external script * resource). The src attribute is only recognized * when the formName attribute is specified. */ protected String src = null; /** * The JavaScript methods will enclosed with html comments if this is set to "true". */ protected String htmlComment = "true"; /** * The generated code should be XHTML compliant when "true". When true, * this setting prevents the htmlComment setting from having an effect. */ protected String xhtml = "false"; /** * Hide JavaScript methods in a CDATA section for XHTML when "true". */ protected String cdata = "true"; private String htmlBeginComment = "\n<!-- Begin \n"; private String htmlEndComment = "//End --> \n"; /** * Gets the key (form name) that will be used * to retrieve a set of validation rules to be * performed on the bean passed in for validation. */ public String getFormName() { return formName; } /** * Sets the key (form name) that will be used * to retrieve a set of validation rules to be * performed on the bean passed in for validation. * Specifying a form name places a * <script> </script> tag around the javascript. */ public void setFormName(String formName) { this.formName = formName; } /** * Gets the current page number of a multi-part form. * Only field validations with a matching page numer * will be generated that match the current page number. * Only valid when the formName attribute is set. */ public int getPage() { return page; } /** * Sets the current page number of a multi-part form. * Only field validations with a matching page numer * will be generated that match the current page number. * Only valid when the formName attribute is set. */ public void setPage(int page) { this.page = page; } /** * Gets the method name that will be used for the Javascript * validation method name if it has a value. This overrides * the auto-generated method name based on the key (form name) * passed in. */ public String getMethod() { return methodName; } /** * Sets the method name that will be used for the Javascript * validation method name if it has a value. This overrides * the auto-generated method name based on the key (form name) * passed in. */ public void setMethod(String methodName) { this.methodName = methodName; } /** * Gets whether or not to generate the static * JavaScript. If this is set to 'true', which * is the default, the static JavaScript will be generated. */ public String getStaticJavascript() { return staticJavascript; } /** * Sets whether or not to generate the static * JavaScript. If this is set to 'true', which * is the default, the static JavaScript will be generated. */ public void setStaticJavascript(String staticJavascript) { this.staticJavascript = staticJavascript; } /** * Gets whether or not to generate the dynamic * JavaScript. If this is set to 'true', which * is the default, the dynamic JavaScript will be generated. */ public String getDynamicJavascript() { return dynamicJavascript; } /** * Sets whether or not to generate the dynamic * JavaScript. If this is set to 'true', which * is the default, the dynamic JavaScript will be generated. */ public void setDynamicJavascript(String dynamicJavascript) { this.dynamicJavascript = dynamicJavascript; } /** * Gets the src attribute's value when defining * the html script element. */ public String getSrc() { return src; } /** * Sets the src attribute's value when defining * the html script element. The src attribute is only recognized * when the formName attribute is specified. */ public void setSrc(String src) { this.src = src; } /** * Gets whether or not to delimit the * JavaScript with html comments. If this is set to 'true', which * is the default, the htmlComment will be surround the JavaScript. */ public String getHtmlComment() { return htmlComment; } /** * Sets whether or not to delimit the * JavaScript with html comments. If this is set to 'true', which * is the default, the htmlComment will be surround the JavaScript. */ public void setHtmlComment(String htmlComment) { this.htmlComment = htmlComment; } /** * Returns the cdata setting "true" or "false". * * @return String - "true" if JavaScript will be hidden in a CDATA section */ public String getCdata() { return cdata; } /** * Sets the cdata status. * * @param cdata The cdata to set */ public void setCdata(String cdata) { this.cdata = cdata; } /** * Gets whether or not to generate the xhtml code. * If this is set to 'true', which is the default, * XHTML will be generated. */ public String getXhtml() { return xhtml; } /** * Sets whether or not to generate the xhtml code. * If this is set to 'true', which is the default, * XHTML will be generated. */ public void setXhtml(String xhtml) { this.xhtml = xhtml; } /** * Render the JavaScript for to perform validations based on the form name. * * @throws javax.servlet.jsp.JspException if a JSP exception has occurred */ public int doStartTag() throws JspException { StringBuffer results = new StringBuffer(); Locale locale = RequestContextUtils.getLocale((HttpServletRequest) pageContext.getRequest()); ValidatorResources resources = getValidatorResources(); Form form = resources.getForm(locale, formName); if (form != null) { if ("true".equalsIgnoreCase(dynamicJavascript)) { MessageSource messages = getMessageSource(); List lActions = new ArrayList(); List lActionMethods = new ArrayList(); // Get List of actions for this Form for (Iterator i = form.getFields().iterator(); i.hasNext();) { Field field = (Field) i.next(); for (Iterator x = field.getDependencyList().iterator(); x.hasNext();) { Object o = x.next(); if (o != null && !lActionMethods.contains(o)) { lActionMethods.add(o); } } } // Create list of ValidatorActions based on lActionMethods for (Iterator i = lActionMethods.iterator(); i.hasNext();) { String depends = (String) i.next(); ValidatorAction va = resources.getValidatorAction(depends); // throw nicer NPE for easier debugging if (va == null) { throw new NullPointerException( "Depends string \"" + depends + "\" was not found in validator-rules.xml."); } String javascript = va.getJavascript(); if (javascript != null && javascript.length() > 0) { lActions.add(va); } else { i.remove(); } } Collections.sort(lActions, new Comparator() { public int compare(Object o1, Object o2) { ValidatorAction va1 = (ValidatorAction) o1; ValidatorAction va2 = (ValidatorAction) o2; if ((va1.getDepends() == null || va1.getDepends().length() == 0) && (va2.getDepends() == null || va2.getDepends().length() == 0)) { return 0; } else if ((va1.getDepends() != null && va1.getDepends().length() > 0) && (va2.getDepends() == null || va2.getDepends().length() == 0)) { return 1; } else if ((va1.getDepends() == null || va1.getDepends().length() == 0) && (va2.getDepends() != null && va2.getDepends().length() > 0)) { return -1; } else { return va1.getDependencyList().size() - va2.getDependencyList().size(); } } }); String methods = null; for (Iterator i = lActions.iterator(); i.hasNext();) { ValidatorAction va = (ValidatorAction) i.next(); if (methods == null) { methods = va.getMethod() + "(form)"; } else { methods += " && " + va.getMethod() + "(form)"; } } results.append(getJavascriptBegin(methods)); for (Iterator i = lActions.iterator(); i.hasNext();) { ValidatorAction va = (ValidatorAction) i.next(); String jscriptVar = null; String functionName = null; if (va.getJsFunctionName() != null && va.getJsFunctionName().length() > 0) { functionName = va.getJsFunctionName(); } else { functionName = va.getName(); } results.append(" function " + functionName + " () { \n"); for (Iterator x = form.getFields().iterator(); x.hasNext();) { Field field = (Field) x.next(); // Skip indexed fields for now until there is a good way to handle // error messages (and the length of the list (could retrieve from scope?)) if (field.isIndexed() || field.getPage() != page || !field.isDependency(va.getName())) { continue; } String message = MessageUtils.getMessage(messages, locale, va, field); message = (message != null) ? message : ""; jscriptVar = this.getNextVar(jscriptVar); results.append(" this." + jscriptVar + " = new Array(\"" + field.getKey() + "\", \"" + message + "\", "); results.append("new Function (\"varName\", \""); Map vars = field.getVars(); // Loop through the field's variables. Iterator varsIterator = vars.keySet().iterator(); while (varsIterator.hasNext()) { String varName = (String) varsIterator.next(); Var var = (Var) vars.get(varName); String varValue = var.getValue(); String jsType = var.getJsType(); // skip requiredif variables field, fieldIndexed, fieldTest, fieldValue if (varName.startsWith("field")) { continue; } if (Var.JSTYPE_INT.equalsIgnoreCase(jsType)) { results.append("this." + varName + "=" + ValidatorUtils.replace(varValue, "\\", "\\\\") + "; "); } else if (Var.JSTYPE_REGEXP.equalsIgnoreCase(jsType)) { results.append("this." + varName + "=/" + ValidatorUtils.replace(varValue, "\\", "\\\\") + "/; "); } else if (Var.JSTYPE_STRING.equalsIgnoreCase(jsType)) { results.append("this." + varName + "='" + ValidatorUtils.replace(varValue, "\\", "\\\\") + "'; "); // So everyone using the latest format doesn't need to change their xml files immediately. } else if ("mask".equalsIgnoreCase(varName)) { results.append("this." + varName + "=/" + ValidatorUtils.replace(varValue, "\\", "\\\\") + "/; "); } else { results.append("this." + varName + "='" + ValidatorUtils.replace(varValue, "\\", "\\\\") + "'; "); } } results.append(" return this[varName];\"));\n"); } results.append(" } \n\n"); } } else if ("true".equalsIgnoreCase(staticJavascript)) { results.append(this.getStartElement()); if ("true".equalsIgnoreCase(htmlComment)) { results.append(htmlBeginComment); } } } if ("true".equalsIgnoreCase(staticJavascript)) { results.append(getJavascriptStaticMethods(resources)); } if (form != null && ("true".equalsIgnoreCase(dynamicJavascript) || "true".equalsIgnoreCase(staticJavascript))) { results.append(getJavascriptEnd()); } JspWriter writer = pageContext.getOut(); try { writer.print(results.toString()); } catch (IOException e) { throw new JspException(e.getMessage()); } return (SKIP_BODY); } /** * Release any acquired resources. */ public void release() { super.release(); // bundle = Globals.MESSAGES_KEY; formName = null; page = 0; methodName = null; staticJavascript = "true"; dynamicJavascript = "true"; htmlComment = "true"; cdata = "true"; src = null; } /** * Returns the opening script element and some initial javascript. */ protected String getJavascriptBegin(String methods) { StringBuffer sb = new StringBuffer(); String name = formName.substring(0, 1).toUpperCase() + formName.substring(1, formName.length()); sb.append(this.getStartElement()); if (this.isXhtml() && "true".equalsIgnoreCase(this.cdata)) { sb.append("//<![CDATA[\r\n"); } if (!this.isXhtml() && "true".equals(htmlComment)) { sb.append(htmlBeginComment); } sb.append("\n var bCancel = false; \n\n"); if (methodName == null || methodName.length() == 0) { sb.append(" function validate" + name + "(form) { \n"); } else { sb.append(" function " + methodName + "(form) { \n"); } sb.append(" if (bCancel) \n"); sb.append(" return true; \n"); sb.append(" else \n"); // Always return true if there aren't any Javascript validation methods if (methods == null || methods.length() == 0) { sb.append(" return true; \n"); } else { sb.append(" return " + methods + "; \n"); } sb.append(" } \n\n"); return sb.toString(); } protected String getJavascriptStaticMethods(ValidatorResources resources) { StringBuffer sb = new StringBuffer(); sb.append("\n\n"); Iterator actions = resources.getValidatorActions().values().iterator(); while (actions.hasNext()) { ValidatorAction va = (ValidatorAction) actions.next(); if (va != null) { String javascript = va.getJavascript(); if (javascript != null && javascript.length() > 0) { sb.append(javascript + "\n"); } } } return sb.toString(); } /** * Returns the closing script element. */ protected String getJavascriptEnd() { StringBuffer sb = new StringBuffer(); sb.append("\n"); if (!this.isXhtml() && "true".equals(htmlComment)) { sb.append(htmlEndComment); } if (this.isXhtml() && "true".equalsIgnoreCase(this.cdata)) { sb.append("//]]>\r\n"); } sb.append("</script>\n\n"); return sb.toString(); } /** * The value <code>null</code> will be returned at the end of the sequence. * ex: "zz" will return <code>null</code> */ private String getNextVar(String input) { if (input == null) { return "aa"; } input = input.toLowerCase(); for (int i = input.length(); i > 0; i--) { int pos = i - 1; char c = input.charAt(pos); c++; if (c <= 'z') { if (i == 0) { return c + input.substring(pos, input.length()); } else if (i == input.length()) { return input.substring(0, pos) + c; } else { return input.substring(0, pos) + c + input.substring(pos, input.length() - 1); } } else { input = replaceChar(input, pos, 'a'); } } return null; } /** * Replaces a single character in a <code>String</code> */ private String replaceChar(String input, int pos, char c) { if (pos == 0) { return c + input.substring(pos, input.length()); } else if (pos == input.length()) { return input.substring(0, pos) + c; } else { return input.substring(0, pos) + c + input.substring(pos, input.length() - 1); } } /** * Constructs the beginning <script> element depending on xhtml status. */ private String getStartElement() { StringBuffer start = new StringBuffer("<script type=\"text/javascript\""); // there is no language attribute in xhtml if (!this.isXhtml()) { start.append(" language=\"Javascript1.1\""); } if (this.src != null) { start.append(" src=\"" + src + "\""); } start.append("> \n"); return start.toString(); } /** * Returns true if this is an xhtml page. */ private boolean isXhtml() { return "true".equalsIgnoreCase(xhtml); } /** * Use the application context itself for default message resolution. */ private MessageSource getMessageSource() { 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); } return requestContext.getWebApplicationContext(); } /** * 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.springmodules.commons.validator.ValidatorFactory). * * @return ValidatorResources from a ValidatorFactory */ private ValidatorResources getValidatorResources() { WebApplicationContext ctx = (WebApplicationContext) pageContext.getRequest() .getAttribute(DispatcherServlet.WEB_APPLICATION_CONTEXT_ATTRIBUTE); if (ctx == null) { // look in main application context (i.e. applicationContext.xml) ctx = WebApplicationContextUtils.getRequiredWebApplicationContext(pageContext.getServletContext()); } ValidatorFactory factory = (ValidatorFactory) BeanFactoryUtils.beanOfTypeIncludingAncestors(ctx, ValidatorFactory.class, true, true); return factory.getValidatorResources(); } }