/*
* Copyright 2002,2004 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.commons.jelly.tags.core;
import java.io.StringReader;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;
import org.apache.commons.jelly.JellyTagException;
import org.apache.commons.jelly.MissingAttributeException;
import org.apache.commons.jelly.Script;
import org.apache.commons.jelly.TagSupport;
import org.apache.commons.jelly.XMLOutput;
import org.apache.commons.jelly.parser.XMLParser;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.xml.sax.ContentHandler;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
import org.xml.sax.XMLReader;
/**
* Parses the output of this tags body or of a given String as a Jelly script
* then either outputting the Script as a variable or executing the script.
*
* @author <a href="mailto:jstrachan@apache.org">James Strachan</a>
* @version $Revision: 155420 $
*/
public class ParseTag extends TagSupport {
/** The Log to which logging calls will be made. */
private static final Log log = LogFactory.getLog(ParseTag.class);
/** The variable that will be generated for the document */
private String var;
/** The markup text to be parsed */
private String text;
/** The XMLReader used to parser the document */
private XMLReader xmlReader;
/** The Jelly parser */
private XMLParser jellyParser;
public ParseTag() {
}
// Tag interface
//-------------------------------------------------------------------------
/* (non-Javadoc)
* @see org.apache.commons.jelly.Tag#doTag(org.apache.commons.jelly.XMLOutput)
*/
public void doTag(XMLOutput output)
throws MissingAttributeException, JellyTagException {
String text = getText();
if (text != null) {
parseText(text);
}
else {
parseBody(output);
}
Script script = getJellyParser().getScript();
if (var != null) {
context.setVariable(var, script);
}
else {
// invoke the script
script.run(context, output);
}
}
// Properties
//-------------------------------------------------------------------------
/** The variable name that will be used for the Document variable created
*/
public String getVar() {
return var;
}
/** Sets the variable name that will be used for the Document variable created
*/
public void setVar(String var) {
this.var = var;
}
/**
* Returns the text to be parsed
* @return String
*/
public String getText() {
return text;
}
/**
* Sets the text to be parsed by this parser
* @param text The text to be parsed by this parser
*/
public void setText(String text) {
this.text = text;
}
/** @return the XMLReader used for parsing, creating one lazily if need be */
public XMLReader getXMLReader() throws ParserConfigurationException, SAXException {
if (xmlReader == null) {
xmlReader = createXMLReader();
}
return xmlReader;
}
/** Sets the XMLReader used for parsing */
public void setXMLReader(XMLReader xmlReader) {
this.xmlReader = xmlReader;
}
/**
* @return XMLParser
*/
public XMLParser getJellyParser() {
if (jellyParser == null) {
jellyParser = createJellyParser();
}
return jellyParser;
}
/**
* Sets the jellyParser.
* @param jellyParser The jellyParser to set
*/
public void setJellyParser(XMLParser jellyParser) {
this.jellyParser = jellyParser;
}
// Implementation methods
//-------------------------------------------------------------------------
/**
* Factory method to create a new XMLReader
*/
protected XMLReader createXMLReader() throws ParserConfigurationException, SAXException {
SAXParserFactory factory = SAXParserFactory.newInstance();
factory.setNamespaceAware(true);
SAXParser parser = factory.newSAXParser();
return parser.getXMLReader();
}
/**
* Parses the body of this tag and returns the parsed document
*/
protected void parseBody(XMLOutput output) throws JellyTagException {
ContentHandler handler = getJellyParser();
XMLOutput newOutput = new XMLOutput(handler);
try {
handler.startDocument();
invokeBody(newOutput);
handler.endDocument();
}
catch (SAXException e) {
throw new JellyTagException(e);
}
}
/**
* Parses the give piece of text as being markup
*/
protected void parseText(String text) throws JellyTagException {
if ( log.isDebugEnabled() ) {
log.debug( "About to parse: " + text );
}
try {
getXMLReader().parse( new InputSource( new StringReader( text ) ) );
}
catch (Exception e) {
throw new JellyTagException(e);
}
}
/**
* Factory method to create a new Jelly parser
* @return XMLParser
*/
protected XMLParser createJellyParser() {
XMLParser answer = new XMLParser();
answer.setContext(context);
return answer;
}
}