/*
* $Header: /home/cvs/jakarta-commons-sandbox/jelly/src/java/org/apache/commons/jelly/tags/core/ChooseTag.java,v 1.5 2002/05/17 15:18:08 jstrachan Exp $
* $Revision: 1.5 $
* $Date: 2002/05/17 15:18:08 $
*
* ====================================================================
*
* The Apache Software License, Version 1.1
*
* Copyright (c) 1999-2002 The Apache Software Foundation. All rights
* reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. The end-user documentation included with the redistribution, if
* any, must include the following acknowlegement:
* "This product includes software developed by the
* Apache Software Foundation (http://www.apache.org/)."
* Alternately, this acknowlegement may appear in the software itself,
* if and wherever such third-party acknowlegements normally appear.
*
* 4. The names "The Jakarta Project", "Commons", and "Apache Software
* Foundation" must not be used to endorse or promote products derived
* from this software without prior written permission. For written
* permission, please contact apache@apache.org.
*
* 5. Products derived from this software may not be called "Apache"
* nor may "Apache" appear in their names without prior written
* permission of the Apache Group.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation. For more
* information on the Apache Software Foundation, please see
* <http://www.apache.org/>.
*
* $Id: ChooseTag.java,v 1.5 2002/05/17 15:18:08 jstrachan Exp $
*/
package org.apache.commons.jelly.tags.core;
import java.io.IOException;
import java.io.Writer;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import org.apache.commons.jelly.CompilableTag;
import org.apache.commons.jelly.JellyContext;
import org.apache.commons.jelly.Script;
import org.apache.commons.jelly.Tag;
import org.apache.commons.jelly.TagSupport;
import org.apache.commons.jelly.XMLOutput;
import org.apache.commons.jelly.impl.ScriptBlock;
import org.apache.commons.jelly.impl.TagScript;
import org.apache.commons.jelly.expression.Expression;
/** A tag which conditionally evaluates its body based on some condition
*
* @author <a href="mailto:jstrachan@apache.org">James Strachan</a>
* @version $Revision: 1.5 $
*/
public class ChooseTag extends TagSupport implements CompilableTag {
private TagScript[] whenTags;
private TagScript otherwiseTag;
public ChooseTag() {
}
// CompilableTag interface
//-------------------------------------------------------------------------
public void compile() throws Exception {
// extract the When tags and the Other tag script
// XXX: iterate through the body....
List whenTagList = new ArrayList();
otherwiseTag = null;
Script body = getBody();
if (body instanceof ScriptBlock) {
ScriptBlock block = (ScriptBlock) body;
for (Iterator iter = block.getScriptList().iterator(); iter.hasNext();) {
Script script = (Script) iter.next();
if (script instanceof TagScript) {
TagScript tagScript = (TagScript) script;
Tag tag = tagScript.getTag();
if (tag instanceof WhenTag) {
whenTagList.add(tagScript);
}
else if (tag instanceof OtherwiseTag) {
otherwiseTag = tagScript;
break;
}
}
}
}
else if (body instanceof TagScript) {
// if only one child tag
TagScript tagScript = (TagScript) body;
Tag tag = tagScript.getTag();
if (tag instanceof WhenTag) {
whenTagList.add(tagScript);
}
else if (tag instanceof OtherwiseTag) {
otherwiseTag = tagScript;
}
}
whenTags = new TagScript[whenTagList.size()];
whenTagList.toArray(whenTags);
}
// Tag interface
//-------------------------------------------------------------------------
public void doTag(XMLOutput output) throws Exception {
for (int i = 0, size = whenTags.length; i < size; i++) {
TagScript script = whenTags[i];
script.run(context, output);
WhenTag tag = (WhenTag) script.getTag();
if (tag.getValue()) {
return;
}
}
if (otherwiseTag != null) {
otherwiseTag.run(context, output);
}
}
}