/*
* $Header: /home/cvs/jakarta-struts/src/share/org/apache/struts/taglib/html/FormTag.java,v 1.61 2004/07/22 01:11:42 niallp Exp $
* $Revision: 1.61 $
* $Date: 2004/07/22 01:11:42 $
*
* Copyright 1999-2004 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.struts.taglib.html;
import java.io.IOException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import javax.servlet.jsp.JspException;
import javax.servlet.jsp.JspWriter;
import javax.servlet.jsp.PageContext;
import javax.servlet.jsp.tagext.TagSupport;
import org.apache.struts.Globals;
import org.apache.struts.action.ActionForm;
import org.apache.struts.action.ActionMapping;
import org.apache.struts.action.ActionServlet;
import org.apache.struts.config.FormBeanConfig;
import org.apache.struts.config.ModuleConfig;
import org.apache.struts.taglib.TagUtils;
import org.apache.struts.util.MessageResources;
import org.apache.struts.util.RequestUtils;
/**
* Custom tag that represents an input form, associated with a bean whose
* properties correspond to the various fields of the form.
*
* @version $Revision: 1.61 $ $Date: 2004/07/22 01:11:42 $
*/
public class FormTag extends TagSupport {
// ----------------------------------------------------- Instance Variables
/**
* The action URL to which this form should be submitted, if any.
*/
protected String action = null;
/**
* The module configuration for our module.
*/
protected ModuleConfig moduleConfig = null;
/**
* The content encoding to be used on a POST submit.
*/
protected String enctype = null;
/**
* The name of the field to receive focus, if any.
*/
protected String focus = null;
/**
* The index in the focus field array to receive focus. This only applies if the field
* given in the focus attribute is actually an array of fields. This allows a specific
* field in a radio button array to receive focus while still allowing indexed field
* names like "myRadioButtonField[1]" to be passed in the focus attribute.
* @since Struts 1.1
*/
protected String focusIndex = null;
/**
* The line ending string.
*/
protected static String lineEnd = System.getProperty("line.separator");
/**
* The ActionMapping defining where we will be submitting this form
*/
protected ActionMapping mapping = null;
/**
* The message resources for this package.
*/
protected static MessageResources messages =
MessageResources.getMessageResources(Constants.Package + ".LocalStrings");
/**
* The request method used when submitting this form.
*/
protected String method = null;
/**
* The onReset event script.
*/
protected String onreset = null;
/**
* The onSubmit event script.
*/
protected String onsubmit = null;
/**
* Include language attribute in the focus script's <script> element. This
* property is ignored in XHTML mode.
* @since Struts 1.2
*/
protected boolean scriptLanguage = true;
/**
* The ActionServlet instance we are associated with (so that we can
* initialize the <code>servlet</code> property on any form bean that
* we create).
*/
protected ActionServlet servlet = null;
/**
* The style attribute associated with this tag.
*/
protected String style = null;
/**
* The style class associated with this tag.
*/
protected String styleClass = null;
/**
* The identifier associated with this tag.
*/
protected String styleId = null;
/**
* The window target.
*/
protected String target = null;
/**
* The name of the form bean to (create and) use. This is either the same
* as the 'name' attribute, if that was specified, or is obtained from the
* associated <code>ActionMapping</code> otherwise.
*/
protected String beanName = null;
/**
* The scope of the form bean to (create and) use. This is either the same
* as the 'scope' attribute, if that was specified, or is obtained from the
* associated <code>ActionMapping</code> otherwise.
*/
protected String beanScope = null;
/**
* The type of the form bean to (create and) use. This is either the same
* as the 'type' attribute, if that was specified, or is obtained from the
* associated <code>ActionMapping</code> otherwise.
*/
protected String beanType = null;
/**
* The list of character encodings for input data that the server should
* accept.
*/
protected String acceptCharset = null;
// ------------------------------------------------------------- Properties
/**
* Return the name of the form bean corresponding to this tag. There is
* no corresponding setter method; this method exists so that the nested
* tag classes can obtain the actual bean name derived from other
* attributes of the tag.
*/
public String getBeanName() {
return beanName;
}
/**
* Return the action URL to which this form should be submitted.
*/
public String getAction() {
return (this.action);
}
/**
* Set the action URL to which this form should be submitted.
*
* @param action The new action URL
*/
public void setAction(String action) {
this.action = action;
}
/**
* Return the content encoding used when submitting this form.
*/
public String getEnctype() {
return (this.enctype);
}
/**
* Set the content encoding used when submitting this form.
*
* @param enctype The new content encoding
*/
public void setEnctype(String enctype) {
this.enctype = enctype;
}
/**
* Return the focus field name for this form.
*/
public String getFocus() {
return (this.focus);
}
/**
* Set the focus field name for this form.
*
* @param focus The new focus field name
*/
public void setFocus(String focus) {
this.focus = focus;
}
/**
* Return the request method used when submitting this form.
*/
public String getMethod() {
return (this.method);
}
/**
* Set the request method used when submitting this form.
*
* @param method The new request method
*/
public void setMethod(String method) {
this.method = method;
}
/**
* Return the onReset event script.
*/
public String getOnreset() {
return (this.onreset);
}
/**
* Set the onReset event script.
*
* @param onReset The new event script
*/
public void setOnreset(String onReset) {
this.onreset = onReset;
}
/**
* Return the onSubmit event script.
*/
public String getOnsubmit() {
return (this.onsubmit);
}
/**
* Set the onSubmit event script.
*
* @param onSubmit The new event script
*/
public void setOnsubmit(String onSubmit) {
this.onsubmit = onSubmit;
}
/**
* Return the style attribute for this tag.
*/
public String getStyle() {
return (this.style);
}
/**
* Set the style attribute for this tag.
*
* @param style The new style attribute
*/
public void setStyle(String style) {
this.style = style;
}
/**
* Return the style class for this tag.
*/
public String getStyleClass() {
return (this.styleClass);
}
/**
* Set the style class for this tag.
*
* @param styleClass The new style class
*/
public void setStyleClass(String styleClass) {
this.styleClass = styleClass;
}
/**
* Return the style identifier for this tag.
*/
public String getStyleId() {
return (this.styleId);
}
/**
* Set the style identifier for this tag.
*
* @param styleId The new style identifier
*/
public void setStyleId(String styleId) {
this.styleId = styleId;
}
/**
* Return the window target.
*/
public String getTarget() {
return (this.target);
}
/**
* Set the window target.
*
* @param target The new window target
*/
public void setTarget(String target) {
this.target = target;
}
/**
* Return the list of character encodings accepted.
*/
public String getAcceptCharset() {
return acceptCharset;
}
/**
* Set the list of character encodings accepted.
*
* @param acceptCharset The list of character encodings
*/
public void setAcceptCharset(String acceptCharset) {
this.acceptCharset= acceptCharset;
}
// --------------------------------------------------------- Public Methods
/**
* Render the beginning of this form.
*
* @exception JspException if a JSP exception has occurred
*/
public int doStartTag() throws JspException {
// Look up the form bean name, scope, and type if necessary
this.lookup();
// Create an appropriate "form" element based on our parameters
StringBuffer results = new StringBuffer();
results.append(this.renderFormStartElement());
results.append(this.renderToken());
TagUtils.getInstance().write(pageContext, results.toString());
// Store this tag itself as a page attribute
pageContext.setAttribute(Constants.FORM_KEY, this, PageContext.REQUEST_SCOPE);
this.initFormBean();
return (EVAL_BODY_INCLUDE);
}
/**
* Locate or create the bean associated with our form.
* @throws JspException
* @since Struts 1.1
*/
protected void initFormBean() throws JspException {
int scope = PageContext.SESSION_SCOPE;
if ("request".equalsIgnoreCase(beanScope)) {
scope = PageContext.REQUEST_SCOPE;
}
Object bean = pageContext.getAttribute(beanName, scope);
if (bean == null) {
// New and improved - use the values from the action mapping
bean =
RequestUtils.createActionForm(
(HttpServletRequest) pageContext.getRequest(),
mapping,
moduleConfig,
servlet);
if (bean instanceof ActionForm) {
((ActionForm) bean).reset(mapping, (HttpServletRequest) pageContext.getRequest());
}
if (bean == null) {
throw new JspException(messages.getMessage("formTag.create", beanType));
}
pageContext.setAttribute(beanName, bean, scope);
}
pageContext.setAttribute(Constants.BEAN_KEY, bean, PageContext.REQUEST_SCOPE);
}
/**
* Generates the opening <code><form></code> element with appropriate
* attributes.
* @since Struts 1.1
*/
protected String renderFormStartElement() {
StringBuffer results = new StringBuffer("<form");
// render attributes
renderName(results);
renderAttribute(results, "method", getMethod() == null ? "post" : getMethod());
renderAction(results);
renderAttribute(results, "accept-charset", getAcceptCharset());
renderAttribute(results, "class", getStyleClass());
renderAttribute(results, "enctype", getEnctype());
renderAttribute(results, "onreset", getOnreset());
renderAttribute(results, "onsubmit", getOnsubmit());
renderAttribute(results, "style", getStyle());
renderAttribute(results, "id", getStyleId());
renderAttribute(results, "target", getTarget());
// Hook for additional attributes
renderOtherAttributes(results);
results.append(">");
return results.toString();
}
/**
* Renders the name attribute
*/
protected void renderName(StringBuffer results) {
results.append(" name=\"");
results.append(beanName);
results.append("\"");
}
/**
* Renders the action attribute
*/
protected void renderAction(StringBuffer results) {
HttpServletResponse response =
(HttpServletResponse) this.pageContext.getResponse();
results.append(" action=\"");
results.append(
response.encodeURL(
TagUtils.getInstance().getActionMappingURL(
this.action,
this.pageContext)));
results.append("\"");
}
/**
* 'Hook' to enable this tag to be extended and
* additional attributes added.
*/
protected void renderOtherAttributes(StringBuffer results) {
}
/**
* Generates a hidden input field with token information, if any.
* @return A hidden input field containing the token.
* @since Struts 1.1
*/
protected String renderToken() {
StringBuffer results = new StringBuffer();
HttpSession session = pageContext.getSession();
if (session != null) {
String token =
(String) session.getAttribute(Globals.TRANSACTION_TOKEN_KEY);
if (token != null) {
results.append("<input type=\"hidden\" name=\"");
results.append(Constants.TOKEN_KEY);
results.append("\" value=\"");
results.append(token);
if (this.isXhtml()) {
results.append("\" />");
} else {
results.append("\">");
}
}
}
return results.toString();
}
/**
* Renders attribute="value" if not null
*/
protected void renderAttribute(StringBuffer results, String attribute, String value) {
if (value != null) {
results.append(" ");
results.append(attribute);
results.append("=\"");
results.append(value);
results.append("\"");
}
}
/**
* Render the end of this form.
*
* @exception JspException if a JSP exception has occurred
*/
public int doEndTag() throws JspException {
// Remove the page scope attributes we created
pageContext.removeAttribute(Constants.BEAN_KEY, PageContext.REQUEST_SCOPE);
pageContext.removeAttribute(Constants.FORM_KEY, PageContext.REQUEST_SCOPE);
// Render a tag representing the end of our current form
StringBuffer results = new StringBuffer("</form>");
// Render JavaScript to set the input focus if required
if (this.focus != null) {
results.append(this.renderFocusJavascript());
}
// Print this value to our output writer
JspWriter writer = pageContext.getOut();
try {
writer.print(results.toString());
} catch (IOException e) {
throw new JspException(messages.getMessage("common.io", e.toString()));
}
// Continue processing this page
return (EVAL_PAGE);
}
/**
* Generates javascript to set the initial focus to the form element given in the
* tag's "focus" attribute.
* @since Struts 1.1
*/
protected String renderFocusJavascript() {
StringBuffer results = new StringBuffer();
results.append(lineEnd);
results.append("<script type=\"text/javascript\"");
if (!this.isXhtml() && this.scriptLanguage) {
results.append(" language=\"JavaScript\"");
}
results.append(">");
results.append(lineEnd);
// xhtml script content shouldn't use the browser hiding trick
if (!this.isXhtml()) {
results.append(" <!--");
results.append(lineEnd);
}
// Construct the control name that will receive focus.
// This does not include any index.
StringBuffer focusControl = new StringBuffer("document.forms[\"");
focusControl.append(beanName);
focusControl.append("\"].elements[\"");
focusControl.append(this.focus);
focusControl.append("\"]");
results.append(" var focusControl = ");
results.append(focusControl.toString());
results.append(";");
results.append(lineEnd);
results.append(lineEnd);
results.append(" if (focusControl.type != \"hidden\" && !focusControl.disabled) {");
results.append(lineEnd);
// Construct the index if needed and insert into focus statement
String index = "";
if (this.focusIndex != null) {
StringBuffer sb = new StringBuffer("[");
sb.append(this.focusIndex);
sb.append("]");
index = sb.toString();
}
results.append(" focusControl");
results.append(index);
results.append(".focus();");
results.append(lineEnd);
results.append(" }");
results.append(lineEnd);
if (!this.isXhtml()) {
results.append(" // -->");
results.append(lineEnd);
}
results.append("</script>");
results.append(lineEnd);
return results.toString();
}
/**
* Release any acquired resources.
*/
public void release() {
super.release();
action = null;
moduleConfig = null;
enctype = null;
focus = null;
focusIndex = null;
mapping = null;
method = null;
onreset = null;
onsubmit = null;
servlet = null;
style = null;
styleClass = null;
styleId = null;
target = null;
acceptCharset = null;
}
// ------------------------------------------------------ Protected Methods
/**
* Look up values for the <code>name</code>, <code>scope</code>, and
* <code>type</code> properties if necessary.
*
* @exception JspException if a required value cannot be looked up
*/
protected void lookup() throws JspException {
// Look up the module configuration information we need
moduleConfig = TagUtils.getInstance().getModuleConfig(pageContext);
if (moduleConfig == null) {
JspException e = new JspException(messages.getMessage("formTag.collections"));
pageContext.setAttribute(Globals.EXCEPTION_KEY, e, PageContext.REQUEST_SCOPE);
throw e;
}
servlet =
(ActionServlet) pageContext.getServletContext().getAttribute(
Globals.ACTION_SERVLET_KEY);
// Look up the action mapping we will be submitting to
String mappingName = TagUtils.getInstance().getActionMappingName(action);
mapping = (ActionMapping) moduleConfig.findActionConfig(mappingName);
if (mapping == null) {
JspException e = new JspException(messages.getMessage("formTag.mapping", mappingName));
pageContext.setAttribute(Globals.EXCEPTION_KEY, e, PageContext.REQUEST_SCOPE);
throw e;
}
// Look up the form bean definition
FormBeanConfig formBeanConfig = moduleConfig.findFormBeanConfig(mapping.getName());
if (formBeanConfig == null) {
JspException e =
new JspException(messages.getMessage("formTag.formBean", mapping.getName(), action));
pageContext.setAttribute(Globals.EXCEPTION_KEY, e, PageContext.REQUEST_SCOPE);
throw e;
}
// Calculate the required values
beanName = mapping.getAttribute();
beanScope = mapping.getScope();
beanType = formBeanConfig.getType();
}
/**
* Returns true if this tag should render as xhtml.
*/
private boolean isXhtml() {
return TagUtils.getInstance().isXhtml(this.pageContext);
}
/**
* Returns the focusIndex.
* @return String
*/
public String getFocusIndex() {
return focusIndex;
}
/**
* Sets the focusIndex.
* @param focusIndex The focusIndex to set
*/
public void setFocusIndex(String focusIndex) {
this.focusIndex = focusIndex;
}
/**
* Gets whether or not the focus script's <script> element will include the
* language attribute.
* @return true if language attribute will be included.
* @since Struts 1.2
*/
public boolean getScriptLanguage() {
return this.scriptLanguage;
}
/**
* Sets whether or not the focus script's <script> element will include the
* language attribute.
* @since Struts 1.2
*/
public void setScriptLanguage(boolean scriptLanguage) {
this.scriptLanguage = scriptLanguage;
}
}