/*
* Copyright 2002-2008 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.springframework.web.servlet.tags.form;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.jsp.JspException;
import javax.servlet.jsp.PageContext;
import org.springframework.beans.PropertyAccessor;
import org.springframework.core.Conventions;
import org.springframework.util.ObjectUtils;
import org.springframework.util.StringUtils;
import org.springframework.web.util.HtmlUtils;
/**
* Databinding-aware JSP tag for rendering an HTML '<code>form</code>' whose
* inner elements are bound to properties on a <em>form object</em>.
*
* <p>Users should place the form object into the
* {@link org.springframework.web.servlet.ModelAndView ModelAndView} when
* populating the data for their view. The name of this form object can be
* configured using the {@link #setModelAttribute "modelAttribute"} property.
*
* <p>The default value for the {@link #setModelAttribute "modelAttribute"}
* property is '<code>command</code>' which corresponds to the default name
* when using the
* {@link org.springframework.web.servlet.mvc.SimpleFormController SimpleFormController}.
*
* @author Rob Harrop
* @author Juergen Hoeller
* @since 2.0
* @see org.springframework.web.servlet.mvc.SimpleFormController
*/
public class FormTag extends AbstractHtmlElementTag {
/** The default HTTP method using which form values are sent to the server: "post" */
private static final String DEFAULT_METHOD = "post";
/** The default attribute name: "command" */
public static final String DEFAULT_COMMAND_NAME = "command";
/** The name of the '<code>modelAttribute</code>' setting */
private static final String MODEL_ATTRIBUTE = "modelAttribute";
/**
* The name of the {@link javax.servlet.jsp.PageContext} attribute under which the
* form object name is exposed.
*/
public static final String MODEL_ATTRIBUTE_VARIABLE_NAME =
Conventions.getQualifiedAttributeName(AbstractFormTag.class, MODEL_ATTRIBUTE);
private static final String ACTION_ATTRIBUTE = "action";
private static final String METHOD_ATTRIBUTE = "method";
private static final String TARGET_ATTRIBUTE = "target";
private static final String ENCTYPE_ATTRIBUTE = "enctype";
private static final String ACCEPT_CHARSET_ATTRIBUTE = "accept-charset";
private static final String ONSUBMIT_ATTRIBUTE = "onsubmit";
private static final String ONRESET_ATTRIBUTE = "onreset";
private static final String AUTOCOMPLETE_ATTRIBUTE = "autocomplete";
private TagWriter tagWriter;
private String modelAttribute = DEFAULT_COMMAND_NAME;
private String name;
private String action;
private String method = DEFAULT_METHOD;
private String target;
private String enctype;
private String acceptCharset;
private String onsubmit;
private String onreset;
private String autocomplete;
/** Caching a previous nested path, so that it may be reset */
private String previousNestedPath;
/**
* Set the name of the form attribute in the model.
* <p>May be a runtime expression.
*/
public void setModelAttribute(String modelAttribute) {
this.modelAttribute = modelAttribute;
}
/**
* Get the name of the form attribute in the model.
*/
protected String getModelAttribute() {
return this.modelAttribute;
}
/**
* Set the name of the form attribute in the model.
* <p>May be a runtime expression.
* @see #setModelAttribute
*/
public void setCommandName(String commandName) {
this.modelAttribute = commandName;
}
/**
* Get the name of the form attribute in the model.
* @see #getModelAttribute
*/
protected String getCommandName() {
return this.modelAttribute;
}
/**
* Set the value of the '<code>name</code>' attribute.
* <p>May be a runtime expression.
* <p>Name is not a valid attribute for form on XHTML 1.0. However,
* it is sometimes needed for backward compatibility.
*/
public void setName(String name) {
this.name = name;
}
/**
* Get the value of the '<code>name</code>' attribute.
*/
protected String getName() throws JspException {
return this.name;
}
/**
* Set the value of the '<code>action</code>' attribute.
* <p>May be a runtime expression.
*/
public void setAction(String action) {
this.action = (action != null ? action : "");
}
/**
* Get the value of the '<code>action</code>' attribute.
*/
protected String getAction() {
return this.action;
}
/**
* Set the value of the '<code>method</code>' attribute.
* <p>May be a runtime expression.
*/
public void setMethod(String method) {
this.method = method;
}
/**
* Get the value of the '<code>method</code>' attribute.
*/
protected String getMethod() {
return this.method;
}
/**
* Set the value of the '<code>target</code>' attribute.
* <p>May be a runtime expression.
*/
public void setTarget(String target) {
this.target = target;
}
/**
* Get the value of the '<code>target</code>' attribute.
*/
public String getTarget() {
return this.target;
}
/**
* Set the value of the '<code>enctype</code>' attribute.
* <p>May be a runtime expression.
*/
public void setEnctype(String enctype) {
this.enctype = enctype;
}
/**
* Get the value of the '<code>enctype</code>' attribute.
*/
protected String getEnctype() {
return this.enctype;
}
/**
* Set the value of the '<code>acceptCharset</code>' attribute.
* <p>May be a runtime expression.
*/
public void setAcceptCharset(String acceptCharset) {
this.acceptCharset = acceptCharset;
}
/**
* Get the value of the '<code>acceptCharset</code>' attribute.
*/
protected String getAcceptCharset() {
return this.acceptCharset;
}
/**
* Set the value of the '<code>onsubmit</code>' attribute.
* <p>May be a runtime expression.
*/
public void setOnsubmit(String onsubmit) {
this.onsubmit = onsubmit;
}
/**
* Get the value of the '<code>onsubmit</code>' attribute.
*/
protected String getOnsubmit() {
return this.onsubmit;
}
/**
* Set the value of the '<code>onreset</code>' attribute.
* <p>May be a runtime expression.
*/
public void setOnreset(String onreset) {
this.onreset = onreset;
}
/**
* Get the value of the '<code>onreset</code>' attribute.
*/
protected String getOnreset() {
return this.onreset;
}
/**
* Set the value of the '<code>autocomplete</code>' attribute.
* May be a runtime expression.
*/
public void setAutocomplete(String autocomplete) {
this.autocomplete = autocomplete;
}
/**
* Get the value of the '<code>autocomplete</code>' attribute.
*/
protected String getAutocomplete() {
return this.autocomplete;
}
/**
* Writes the opening part of the block '<code>form</code>' tag and exposes
* the form object name in the {@link javax.servlet.jsp.PageContext}.
* @param tagWriter the {@link TagWriter} to which the form content is to be written
* @return {@link javax.servlet.jsp.tagext.Tag#EVAL_BODY_INCLUDE}
*/
protected int writeTagContent(TagWriter tagWriter) throws JspException {
this.tagWriter = tagWriter;
tagWriter.startTag("form");
writeDefaultAttributes(tagWriter);
tagWriter.writeAttribute(ACTION_ATTRIBUTE, resolveAction());
writeOptionalAttribute(tagWriter, METHOD_ATTRIBUTE, getMethod());
writeOptionalAttribute(tagWriter, TARGET_ATTRIBUTE, getTarget());
writeOptionalAttribute(tagWriter, ENCTYPE_ATTRIBUTE, getEnctype());
writeOptionalAttribute(tagWriter, ACCEPT_CHARSET_ATTRIBUTE, getAcceptCharset());
writeOptionalAttribute(tagWriter, ONSUBMIT_ATTRIBUTE, getOnsubmit());
writeOptionalAttribute(tagWriter, ONRESET_ATTRIBUTE, getOnreset());
writeOptionalAttribute(tagWriter, AUTOCOMPLETE_ATTRIBUTE, getAutocomplete());
tagWriter.forceBlock();
// Expose the form object name for nested tags...
String modelAttribute = resolveModelAttribute();
this.pageContext.setAttribute(MODEL_ATTRIBUTE_VARIABLE_NAME, modelAttribute, PageContext.REQUEST_SCOPE);
this.pageContext.setAttribute(COMMAND_NAME_VARIABLE_NAME, modelAttribute, PageContext.REQUEST_SCOPE);
// Save previous nestedPath value, build and expose current nestedPath value.
// Use request scope to expose nestedPath to included pages too.
this.previousNestedPath =
(String) this.pageContext.getAttribute(NESTED_PATH_VARIABLE_NAME, PageContext.REQUEST_SCOPE);
this.pageContext.setAttribute(NESTED_PATH_VARIABLE_NAME,
modelAttribute + PropertyAccessor.NESTED_PROPERTY_SEPARATOR, PageContext.REQUEST_SCOPE);
return EVAL_BODY_INCLUDE;
}
/**
* Autogenerated IDs correspond to the form object name.
*/
protected String autogenerateId() throws JspException {
return resolveModelAttribute();
}
/**
* {@link #evaluate Resolves} and returns the name of the form object.
* @throws IllegalArgumentException if the form object resolves to <code>null</code>
*/
protected String resolveModelAttribute() throws JspException {
Object resolvedModelAttribute = evaluate(MODEL_ATTRIBUTE, getModelAttribute());
if (resolvedModelAttribute == null) {
throw new IllegalArgumentException(MODEL_ATTRIBUTE + " must not be null");
}
return (String) resolvedModelAttribute;
}
/**
* Resolve the value of the '<code>action</code>' attribute.
* <p>If the user configured an '<code>action</code>' value then
* the result of evaluating this value is used. Otherwise, the
* {@link org.springframework.web.servlet.support.RequestContext#getRequestUri() originating URI}
* is used.
* @return the value that is to be used for the '<code>action</code>' attribute
*/
protected String resolveAction() throws JspException {
String action = getAction();
if (StringUtils.hasText(action)) {
return getDisplayString(evaluate(ACTION_ATTRIBUTE, action));
}
else {
String requestUri = getRequestContext().getRequestUri();
ServletResponse response = this.pageContext.getResponse();
if (response instanceof HttpServletResponse) {
requestUri = ((HttpServletResponse) response).encodeURL(requestUri);
String queryString = getRequestContext().getQueryString();
if (StringUtils.hasText(queryString)) {
requestUri += "?" + HtmlUtils.htmlEscape(queryString);
}
}
if (StringUtils.hasText(requestUri)) {
return requestUri;
}
else {
throw new IllegalArgumentException("Attribute 'action' is required. " +
"Attempted to resolve against current request URI but request URI was null.");
}
}
}
/**
* Closes the '<code>form</code>' block tag and removes the form object name
* from the {@link javax.servlet.jsp.PageContext}.
*/
public int doEndTag() throws JspException {
this.tagWriter.endTag();
this.pageContext.removeAttribute(MODEL_ATTRIBUTE_VARIABLE_NAME, PageContext.REQUEST_SCOPE);
this.pageContext.removeAttribute(COMMAND_NAME_VARIABLE_NAME, PageContext.REQUEST_SCOPE);
if (this.previousNestedPath != null) {
// Expose previous nestedPath value.
this.pageContext.setAttribute(NESTED_PATH_VARIABLE_NAME, this.previousNestedPath, PageContext.REQUEST_SCOPE);
}
else {
// Remove exposed nestedPath value.
this.pageContext.removeAttribute(NESTED_PATH_VARIABLE_NAME, PageContext.REQUEST_SCOPE);
}
return EVAL_PAGE;
}
/**
* Clears the stored {@link TagWriter}.
*/
public void doFinally() {
super.doFinally();
this.tagWriter = null;
this.previousNestedPath = null;
}
/**
* Override resolve CSS class since error class is not supported.
*/
protected String resolveCssClass() throws JspException {
return ObjectUtils.getDisplayString(evaluate("cssClass", getCssClass()));
}
/**
* Unsupported for forms.
* @throws UnsupportedOperationException always
*/
public void setPath(String path) {
throw new UnsupportedOperationException("The 'path' attribute is not supported for forms");
}
/**
* Unsupported for forms.
* @throws UnsupportedOperationException always
*/
public void setCssErrorClass(String cssErrorClass) {
throw new UnsupportedOperationException("The 'cssErrorClass' attribute is not supported for forms");
}
}