Java tutorial
/* * Copyright 2003-2004 The Apache Software Foundation. * * 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.apache.velocity.tools.struts; import java.util.ArrayList; import java.util.Comparator; import java.util.Collections; import java.util.Iterator; import java.util.List; import java.util.Locale; import java.util.Map; import javax.servlet.ServletContext; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpSession; import org.apache.commons.validator.Field; import org.apache.commons.validator.Form; import org.apache.commons.validator.ValidatorAction; import org.apache.commons.validator.ValidatorResources; import org.apache.commons.validator.util.ValidatorUtils; import org.apache.commons.validator.Var; import org.apache.struts.Globals; import org.apache.struts.config.ActionConfig; import org.apache.struts.config.ModuleConfig; import org.apache.struts.util.MessageResources; import org.apache.struts.util.ModuleUtils; import org.apache.struts.validator.Resources; import org.apache.struts.validator.ValidatorPlugIn; import org.apache.velocity.tools.view.context.ViewContext; import org.apache.velocity.tools.view.tools.ViewTool; import java.util.StringTokenizer; /** * <p>View tool that works with Struts Validator to * produce client side javascript validation for your forms.</p> * <p>Usage: * <pre> * Template example: * * $validator.getJavascript("nameOfYourForm") * * Toolbox configuration: * <tool> * <key>validator</key> * <scope>request</scope> * <class>org.apache.velocity.tools.struts.ValidatorTool</class> * </tool> * </pre> * </p> * <p>This is an adaptation of the JavascriptValidatorTag * from the Struts 1.1 validator library.</p> * * @author David Winterfeldt * @author David Graham * @author <a href="mailto:marinoj@centrum.is">Marino A. Jonsson</a> * @author <a href="mailto:nathan@esha.com">Nathan Bubna</a> * @since VelocityTools 1.1 * @version $Revision: 326310 $ $Date: 2005-10-18 17:47:39 -0700 (Tue, 18 Oct 2005) $ */ public class ValidatorTool implements ViewTool { /** A reference to the ViewContext */ protected ViewContext context; /** A reference to the ServletContext */ protected ServletContext app; /** A reference to the HttpServletRequest. */ protected HttpServletRequest request; /** A reference to the HttpSession. */ protected HttpSession session; /** A reference to the ValidatorResources. */ protected ValidatorResources resources; private static final String HTML_BEGIN_COMMENT = "\n<!-- Begin \n"; private static final String HTML_END_COMMENT = "//End --> \n"; private boolean xhtml = false; private boolean htmlComment = true; private boolean cdata = true; private String formName = null; private String methodName = null; private String src = null; private int page = 0; /** * formName is used for both Javascript and non-javascript validations. * For the javascript validations, there is the possibility that we will * be rewriting the formName (if it is a ValidatorActionForm instead of just * a ValidatorForm) so we need another variable to hold the formName just for * javascript usage. */ protected String jsFormName = null; /** * A Comparator to use when sorting ValidatorAction objects. */ private static final Comparator actionComparator = 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(); } } }; /** * Default constructor. Tool must be initialized before use. */ public ValidatorTool() { } /** * Initializes this tool. * * @param obj the current ViewContext * @throws IllegalArgumentException if the param is not a ViewContext */ public void init(Object obj) { if (!(obj instanceof ViewContext)) { throw new IllegalArgumentException("Tool can only be initialized with a ViewContext"); } this.context = (ViewContext) obj; this.request = context.getRequest(); this.session = request.getSession(false); this.app = context.getServletContext(); Boolean b = (Boolean) context.getAttribute(ViewContext.XHTML); if (b != null) { this.xhtml = b.booleanValue(); } /* Is there a mapping associated with this request? */ ActionConfig config = (ActionConfig) request.getAttribute(Globals.MAPPING_KEY); if (config != null) { /* Is there a form bean associated with this mapping? */ this.formName = config.getAttribute(); } ModuleConfig mconfig = ModuleUtils.getInstance().getModuleConfig(request, app); this.resources = (ValidatorResources) app.getAttribute(ValidatorPlugIn.VALIDATOR_KEY + mconfig.getPrefix()); } /****************** get/set accessors ***************/ /** * Gets the current page number of a multi-part form. * Only field validations with a matching page number * will be generated that match the current page number. * Only valid when the formName attribute is set. * * @return the current page number of a multi-part form */ public int getPage() { return page; } /** * Sets the current page number of a multi-part form. * Only field validations with a matching page number * will be generated that match the current page number. * * @param page the current page number of a multi-part form */ 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. * * @return the method name that will be used for the Javascript validation method */ 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. * * @param methodName the method name that will be used for the Javascript validation method name */ public void setMethod(String methodName) { this.methodName = methodName; } /** * Gets whether or not to delimit the * JavaScript with html comments. If this is set to 'true', which * is the default, html comments will surround the JavaScript. * * @return true if the JavaScript should be delimited with html comments */ public boolean getHtmlComment() { return this.htmlComment; } /** * Sets whether or not to delimit the * JavaScript with html comments. If this is set to 'true', which * is the default, html comments will surround the JavaScript. * * @param htmlComment whether or not to delimit the JavaScript with html comments */ public void setHtmlComment(boolean htmlComment) { this.htmlComment = htmlComment; } /** * Gets the src attribute's value when defining * the html script element. * * @return the src attribute's value */ public String getSrc() { return src; } /** * Sets the src attribute's value (used to include * an external script resource) when defining * the html script element. The src attribute is only recognized * when the formName attribute is specified. * * @param src the src attribute's value */ public void setSrc(String src) { this.src = src; } /** * Returns the cdata setting "true" or "false". * * @return boolean - "true" if JavaScript will be hidden in a CDATA section */ public boolean getCdata() { return cdata; } /** * Sets the cdata status. * @param cdata The cdata to set */ public void setCdata(boolean cdata) { this.cdata = cdata; } /****************** methods that aren't just accessors ***************/ /** * Render both dynamic and static JavaScript to perform * validations based on the form name attribute of the action * mapping associated with the current request (if such exists). * * @return the javascript for the current form * @throws Exception */ public String getJavascript() throws Exception { return getJavascript(this.formName); } /** * Render both dynamic and static JavaScript to perform * validations based on the supplied form name. * * @param formName the key (form name) * @return the Javascript for the specified form * @throws Exception */ public String getJavascript(String formName) throws Exception { this.formName = formName; return getJavascript(formName, true); } /** * Render just the dynamic JavaScript to perform validations based * on the form name attribute of the action mapping associated * with the current request (if such exists). Useful i.e. if the static * parts are located in a seperate .js file. * * @return the javascript for the current form * @throws Exception */ public String getDynamicJavascript() throws Exception { return getDynamicJavascript(this.formName); } /** * Render just the static JavaScript methods. Useful i.e. if the static * parts should be located in a seperate .js file. * * @return all static Javascript methods * @throws Exception */ public String getStaticJavascript() throws Exception { StringBuffer results = new StringBuffer(); results.append(getStartElement()); if (this.htmlComment) { results.append(HTML_BEGIN_COMMENT); } results.append(getJavascriptStaticMethods(resources)); results.append(getJavascriptEnd()); return results.toString(); } /** * Render just the dynamic JavaScript to perform validations based * on the supplied form name. Useful i.e. if the static * parts are located in a seperate .js file. * * @param formName the key (form name) * @return the dynamic Javascript for the specified form * @throws Exception */ public String getDynamicJavascript(String formName) throws Exception { this.formName = formName; return getJavascript(formName, false); } /** * Render both dynamic and static JavaScript to perform * validations based on the supplied form name. * * @param formName the key (form name) * @param getStatic indicates if the static methods should be rendered * @return the Javascript for the specified form * @throws Exception */ protected String getJavascript(String formName, boolean getStatic) throws Exception { StringBuffer results = new StringBuffer(); Locale locale = StrutsUtils.getLocale(request, session); Form form = resources.getForm(locale, formName); if (form != null) { results.append(getDynamicJavascript(resources, locale, form)); } if (getStatic) { results.append(getJavascriptStaticMethods(resources)); } if (form != null) { results.append(getJavascriptEnd()); } return results.toString(); } /** * Generates the dynamic JavaScript for the form. * * @param resources the validator resources * @param locale the locale for the current request * @param form the form to generate javascript for * @return the dynamic javascript */ protected String getDynamicJavascript(ValidatorResources resources, Locale locale, Form form) { StringBuffer results = new StringBuffer(); MessageResources messages = StrutsUtils.getMessageResources(request, app); List actions = createActionList(resources, form); final String methods = createMethods(actions); String formName = form.getName(); jsFormName = formName; if (jsFormName.charAt(0) == '/') { String mappingName = StrutsUtils.getActionMappingName(jsFormName); ModuleConfig mconfig = ModuleUtils.getInstance().getModuleConfig(request, app); ActionConfig mapping = (ActionConfig) mconfig.findActionConfig(mappingName); if (mapping == null) { throw new NullPointerException("Cannot retrieve mapping for action " + mappingName); } jsFormName = mapping.getAttribute(); } results.append(getJavascriptBegin(methods)); for (Iterator i = actions.iterator(); i.hasNext();) { ValidatorAction va = (ValidatorAction) i.next(); int jscriptVar = 0; String functionName = null; if (va.getJsFunctionName() != null && va.getJsFunctionName().length() > 0) { functionName = va.getJsFunctionName(); } else { functionName = va.getName(); } results.append(" function "); results.append(jsFormName); results.append("_"); results.append(functionName); results.append(" () { \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 = Resources.getMessage(messages, locale, va, field); message = (message != null) ? message : ""; //jscriptVar = this.getNextVar(jscriptVar); results.append(" this.a"); results.append(jscriptVar++); results.append(" = new Array(\""); results.append(field.getKey()); // TODO: escape? results.append("\", \""); results.append(escapeJavascript(message)); results.append("\", "); 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(); // TODO: escape? 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; } // these are appended no matter what jsType is results.append("this."); results.append(varName); String escapedVarValue = escapeJavascript(varValue); if (Var.JSTYPE_INT.equalsIgnoreCase(jsType)) { results.append("="); results.append(escapedVarValue); results.append("; "); } else if (Var.JSTYPE_REGEXP.equalsIgnoreCase(jsType)) { results.append("=/"); results.append(escapedVarValue); results.append("/; "); } else if (Var.JSTYPE_STRING.equalsIgnoreCase(jsType)) { results.append("='"); results.append(escapedVarValue); results.append("'; "); } // So everyone using the latest format // doesn't need to change their xml files immediately. else if ("mask".equalsIgnoreCase(varName)) { results.append("=/"); results.append(escapedVarValue); results.append("/; "); } else { results.append("='"); results.append(escapedVarValue); results.append("'; "); } } results.append(" return this[varName];\"));\n"); } results.append(" } \n\n"); } return results.toString(); } /** * <p>Backslash-escapes the following characters from the input string: * ", ', \, \r, \n.</p> * * <p>This method escapes characters that will result in an invalid * Javascript statement within the validator Javascript.</p> * * @param str The string to escape. * @return The string <code>s</code> with each instance of a double quote, * single quote, backslash, carriage-return, or line feed escaped * with a leading backslash. * @since VelocityTools 1.2 */ protected String escapeJavascript(String str) { if (str == null) { return null; } int length = str.length(); if (length == 0) { return str; } // guess at how many chars we'll be adding... StringBuffer out = new StringBuffer(length + 4); // run through the string escaping sensitive chars for (int i = 0; i < length; i++) { char c = str.charAt(i); if (c == '"' || c == '\'' || c == '\\' || c == '\n' || c == '\r') { out.append('\\'); } out.append(c); } return out.toString(); } /** * Creates the JavaScript methods list from the given actions. * @param actions A List of ValidatorAction objects. * @return JavaScript methods. */ protected String createMethods(List actions) { String methodOperator = " && "; StringBuffer methods = null; for (Iterator i = actions.iterator(); i.hasNext();) { ValidatorAction va = (ValidatorAction) i.next(); if (methods == null) { methods = new StringBuffer(va.getMethod()); } else { methods.append(methodOperator); methods.append(va.getMethod()); } methods.append("(form)"); } return methods.toString(); } /** * Get List of actions for the given Form. * * @param resources the validator resources * @param form the form for which the actions are requested * @return A sorted List of ValidatorAction objects. */ protected List createActionList(ValidatorResources resources, Form form) { List actionMethods = 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 && !actionMethods.contains(o)) { actionMethods.add(o); } } } List actions = new ArrayList(); // Create list of ValidatorActions based on actionMethods for (Iterator i = actionMethods.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) { actions.add(va); } else { i.remove(); } } Collections.sort(actions, actionComparator); return actions; } /** * Returns the opening script element and some initial javascript. * * @param methods javascript validation methods * @return the opening script element and some initial javascript */ protected String getJavascriptBegin(String methods) { StringBuffer sb = new StringBuffer(); String name = jsFormName.replace('/', '_'); // remove any '/' characters name = jsFormName.substring(0, 1).toUpperCase() + jsFormName.substring(1, jsFormName.length()); sb.append(this.getStartElement()); if (this.xhtml && this.cdata) { sb.append("<![CDATA[\r\n"); } if (!this.xhtml && this.htmlComment) { sb.append(HTML_BEGIN_COMMENT); } sb.append("\n var bCancel = false; \n\n"); if (methodName == null || methodName.length() == 0) { sb.append(" function validate"); sb.append(name); } else { sb.append(" function "); sb.append(methodName); } sb.append("(form) {"); //FIXME? anyone know why all these spaces need to be here? sb.append(" \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 { //Making Sure that Bitwise operator works: sb.append(" var formValidationResult;\n"); sb.append(" formValidationResult = " + methods + "; \n"); sb.append(" return (formValidationResult == 1);\n"); } sb.append(" } \n\n"); return sb.toString(); } /** * * @param resources the validation resources * @return the static javascript methods */ protected String getJavascriptStaticMethods(ValidatorResources resources) { StringBuffer sb = new StringBuffer("\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. * * @return the closing script element */ protected String getJavascriptEnd() { StringBuffer sb = new StringBuffer(); sb.append("\n"); if (!this.xhtml && this.htmlComment) { sb.append(HTML_END_COMMENT); } if (this.xhtml && this.cdata) { sb.append("]]>\r\n"); } sb.append("</script>\n\n"); return sb.toString(); } /** * Constructs the beginning <script> element depending on xhtml status. * * @return 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.xhtml) { start.append(" language=\"Javascript1.1\""); } if (this.src != null) { start.append(" src=\"" + src + "\""); } start.append("> \n"); return start.toString(); } }