/*
* The contents of this file are subject to the terms
* of the Common Development and Distribution License
* (the "License"). You may not use this file except
* in compliance with the License.
*
* You can obtain a copy of the license at
* glassfish/bootstrap/legal/CDDLv1.0.txt or
* https://glassfish.dev.java.net/public/CDDLv1.0.html.
* See the License for the specific language governing
* permissions and limitations under the License.
*
* When distributing Covered Code, include this CDDL
* HEADER in each file and include the License file at
* glassfish/bootstrap/legal/CDDLv1.0.txt. If applicable,
* add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your
* own identifying information: Portions Copyright [yyyy]
* [name of copyright owner]
*
* Copyright 2005 Sun Microsystems, Inc. All rights reserved.
*
* Portions Copyright Apache Software Foundation.
*/
package org.apache.taglibs.standard.tag.common.core;
import javax.servlet.jsp.JspException;
import javax.servlet.jsp.JspTagException;
import javax.servlet.jsp.jstl.core.ConditionalTagSupport;
import javax.servlet.jsp.tagext.Tag;
import org.apache.taglibs.standard.resources.Resources;
/**
* <p>WhenTagSupport is an abstract class that facilitates
* implementation of <when>-style tags in both the rtexprvalue
* and expression-evaluating libraries. It also supports
* <otherwise>.</p>
*
* <p>In particular, this base class does the following:</p>
*
* <ul>
* <li> overrides ConditionalTagSupport.doStartTag() to implement the
* appropriate semantics of subtags of <choose> </li>
* </ul>
*
* @author Shawn Bayern
*/
public abstract class WhenTagSupport extends ConditionalTagSupport
{
//*********************************************************************
// Implementation of exclusive-conditional behavior
/*
* Includes its body if condition() evalutes to true AND its parent
* ChooseTag wants it to do so. The condition will not even be
* evaluated if ChooseTag instructs us not to run.
*/
public int doStartTag() throws JspException {
Tag parent;
// make sure we're contained properly
if (!((parent = getParent()) instanceof ChooseTag))
throw new JspTagException(
Resources.getMessage("WHEN_OUTSIDE_CHOOSE"));
// make sure our parent wants us to continue
if (!((ChooseTag) parent).gainPermission())
return SKIP_BODY; // we've been reeled in
// handle conditional behavior
if (condition()) {
((ChooseTag) parent).subtagSucceeded();
return EVAL_BODY_INCLUDE;
} else
return SKIP_BODY;
}
}