/*
* Copyright 1999-2004 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.cocoon.generation;
import java.io.ByteArrayInputStream;
import java.io.IOException;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.cocoon.ProcessingException;
import org.apache.cocoon.components.jsp.JSPEngine;
import org.apache.cocoon.environment.http.HttpEnvironment;
import org.apache.excalibur.source.Source;
import org.apache.excalibur.xml.sax.SAXParser;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
/**
* Allows Servlets and JSPs to be used as a generator.
*
* @author <a href="mailto:dims@yahoo.com">Davanum Srinivas</a>
* @version CVS $Id: JSPGenerator.java,v 1.6 2004/05/05 21:39:28 joerg Exp $
*/
public class JSPGenerator extends ServiceableGenerator {
/**
* Generate XML data from JSPEngine output.
*/
public void generate() throws ProcessingException {
final HttpServletResponse servletResponse =
(HttpServletResponse) this.objectModel.get(HttpEnvironment.HTTP_RESPONSE_OBJECT);
final HttpServletRequest servletRequest =
(HttpServletRequest) this.objectModel.get(HttpEnvironment.HTTP_REQUEST_OBJECT);
final ServletContext servletContext =
(ServletContext) this.objectModel.get(HttpEnvironment.HTTP_SERVLET_CONTEXT);
// ensure that we are running in a servlet environment
if (servletResponse == null || servletRequest == null || servletContext == null) {
throw new ProcessingException("JSPGenerator can only be used from within a Servlet environment.");
}
JSPEngine engine = null;
SAXParser parser = null;
Source inputSource = null;
Source contextSource = null;
try {
inputSource = this.resolver.resolveURI(this.source);
contextSource = this.resolver.resolveURI("context:/");
String inputSourceURI = inputSource.getURI();
String contextSourceURI = contextSource.getURI();
if (!inputSourceURI.startsWith(contextSourceURI)) {
throw new ProcessingException("You must not reference a file "
+ "outside of the servlet context at " + contextSourceURI + ".");
}
String url = inputSourceURI.substring(contextSourceURI.length());
if (url.charAt(0) != '/') {
url = "/" + url;
}
if (getLogger().isDebugEnabled()) {
getLogger().debug("JSPGenerator executing:" + url);
}
engine = (JSPEngine) super.manager.lookup(JSPEngine.ROLE);
byte[] bytes = engine.executeJSP(url, servletRequest, servletResponse, servletContext);
InputSource input = new InputSource(new ByteArrayInputStream(bytes));
// utf-8 is default encoding; specified explicitely here as a reminder.
input.setEncoding("utf-8");
// pipe the results into the parser
parser = (SAXParser) super.manager.lookup(SAXParser.ROLE);
parser.parse(input, super.xmlConsumer);
} catch (ServletException e) {
throw new ProcessingException("ServletException while executing JSPEngine", e);
} catch (SAXException e) {
throw new ProcessingException("SAXException while parsing JSPEngine output", e);
} catch (IOException e) {
throw new ProcessingException("IOException JSPGenerator.generate()", e);
} catch (ProcessingException e) {
throw e;
} catch (Exception e) {
throw new ProcessingException("Exception JSPGenerator.generate()", e);
} finally {
super.manager.release(parser);
super.manager.release(engine);
this.resolver.release(inputSource);
this.resolver.release(contextSource);
}
}
}