/*
* $Header: /home/cvs/jakarta-commons-sandbox/jelly/src/java/org/apache/commons/jelly/tags/xml/ParseTag.java,v 1.9 2002/06/26 09:24:35 jstrachan Exp $
* $Revision: 1.9 $
* $Date: 2002/06/26 09:24:35 $
*
* ====================================================================
*
* 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: ParseTag.java,v 1.9 2002/06/26 09:24:35 jstrachan Exp $
*/
package org.apache.commons.jelly.tags.xml;
import java.io.InputStream;
import java.io.Reader;
import java.io.StringReader;
import java.io.StringWriter;
import java.io.Writer;
import java.net.MalformedURLException;
import java.net.URL;
import org.apache.commons.jelly.TagSupport;
import org.apache.commons.jelly.XMLOutput;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.dom4j.Document;
import org.dom4j.io.SAXContentHandler;
import org.dom4j.io.SAXReader;
/**
* An abstract base class for any tag which parsers its body as XML.
*
* @author <a href="mailto:jstrachan@apache.org">James Strachan</a>
* @version $Revision: 1.9 $
*/
public abstract class ParseTagSupport extends TagSupport {
/** The Log to which logging calls will be made. */
private static final Log log = LogFactory.getLog(ParseTagSupport.class);
/** The variable that will be generated for the document */
private String var;
/** The SAXReader used to parser the document */
private SAXReader saxReader;
public ParseTagSupport() {
}
// 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;
}
/** @return the SAXReader used for parsing, creating one lazily if need be */
public SAXReader getSAXReader() throws Exception {
if (saxReader == null) {
saxReader = createSAXReader();
}
return saxReader;
}
/** Sets the SAXReader used for parsing */
public void setSAXReader(SAXReader saxReader) {
this.saxReader = saxReader;
}
// Implementation methods
//-------------------------------------------------------------------------
/**
* Factory method to create a new SAXReader
*/
protected abstract SAXReader createSAXReader() throws Exception;
/**
* Parses the body of this tag and returns the parsed document
*/
protected Document parseBody(XMLOutput output) throws Exception {
SAXContentHandler handler = new SAXContentHandler();
XMLOutput newOutput = new XMLOutput(handler);
handler.startDocument();
invokeBody( newOutput);
handler.endDocument();
return handler.getDocument();
/*
// the following is inefficient as it requires a parse of the text
// but is left here in the code to see how it could be done.
String text = getBodyText();
if ( log.isDebugEnabled() ) {
log.debug( "About to parse: " + text );
}
return getSAXReader().read( new StringReader( text ) );
*/
}
/**
* Parses the given source
*/
protected Document parse(Object source) throws Exception {
// #### we should allow parsing to output XML events to
// the output if no var is specified
if (source instanceof String) {
String uri = (String) source;
InputStream in = context.getResourceAsStream(uri);
return getSAXReader().read(in, uri);
}
else if (source instanceof Reader) {
return getSAXReader().read((Reader) source);
}
else if (source instanceof InputStream) {
return getSAXReader().read((InputStream) source);
}
else if (source instanceof URL) {
return getSAXReader().read((URL) source);
}
else {
throw new IllegalArgumentException(
"Invalid source argument. Must be a String, Reader, InputStream or URL."
+ " Was type; "
+ source.getClass().getName()
+ " with value: "
+ source);
}
}
}