/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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.components.flow.util;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.Map;
import org.apache.avalon.framework.activity.Disposable;
import org.apache.avalon.framework.context.Context;
import org.apache.avalon.framework.context.ContextException;
import org.apache.avalon.framework.context.Contextualizable;
import org.apache.avalon.framework.service.ServiceException;
import org.apache.avalon.framework.service.ServiceManager;
import org.apache.avalon.framework.service.Serviceable;
import org.apache.cocoon.ProcessingException;
import org.apache.cocoon.components.ContextHelper;
import org.apache.cocoon.components.flow.FlowHelper;
import org.apache.cocoon.components.flow.javascript.JavaScriptFlowHelper;
import org.apache.cocoon.components.source.SourceUtil;
import org.apache.commons.io.IOUtils;
import org.apache.excalibur.source.Source;
import org.apache.excalibur.source.SourceResolver;
import org.w3c.dom.Document;
import org.xml.sax.ContentHandler;
import org.xml.sax.SAXException;
/**
* Utility class to process a pipeline to various destinations.
* This class must be setup from the flowscript before being used. This means that instances must
* be created with <code>cocoon.createObject(Packages.org.apache.cocoon.components.flow.util.PipelineUtil);
*
* @author <a href="http://www.apache.org/~sylvain/">Sylvain Wallez</a>
* @version CVS $Id$
*/
public class PipelineUtil implements Contextualizable, Serviceable, Disposable {
private Context context;
private ServiceManager manager;
private SourceResolver resolver;
/* (non-Javadoc)
* @see org.apache.avalon.framework.activity.Disposable#dispose()
*/
public void dispose() {
if (this.manager != null) {
this.manager.release(this.resolver);
this.manager = null;
this.resolver = null;
}
}
public void contextualize(Context context) throws ContextException {
this.context = context;
}
public void service(ServiceManager manager) throws ServiceException {
this.manager = manager;
this.resolver = (SourceResolver)manager.lookup(SourceResolver.ROLE);
}
/**
* Check that this object has been correctly set up.
*
* @throws IllegalStateException if not already set up.
*/
private void checkSetup() {
if (this.manager == null) {
throw new IllegalStateException("Instances of " + getClass().getName() +
" must be setup using either cocoon.createObject() or cocoon.setupObject().");
}
}
/**
* Process a pipeline to a stream.
*
* @param uri the pipeline URI
* @param viewData the view data object
* @param output the stream where pipeline result is output. Note: this stream is not closed.
* @throws IOException
*/
public void processToStream(String uri, Object viewData, OutputStream output)
throws IOException {
checkSetup();
Map objectModel = ContextHelper.getObjectModel(this.context);
// Keep the previous view data, if any (is it really necessary?), and set the new one
Object oldViewData = FlowHelper.getContextObject(objectModel);
FlowHelper.setContextObject(objectModel, JavaScriptFlowHelper.unwrap(viewData));
Source src = null;
InputStream input = null;
try {
src = this.resolver.resolveURI("cocoon:/" + uri);
input = src.getInputStream();
IOUtils.copy(input, output);
} finally {
if (input != null) {
try {
input.close();
} catch (IOException ignored) {}
}
// Restore the previous view data
FlowHelper.setContextObject(objectModel, oldViewData);
if (src != null) {
this.resolver.release(src);
}
}
}
/**
* Process a pipeline to a SAX <code>ContentHandler</code>
*
* @param uri the pipeline URI
* @param viewData the view data object
* @param handler where the pipeline should be streamed to.
*/
public void processToSAX(String uri, Object viewData, ContentHandler handler)
throws SAXException, IOException, ProcessingException {
checkSetup();
Map objectModel = ContextHelper.getObjectModel(this.context);
Object oldViewData = FlowHelper.getContextObject(objectModel);
FlowHelper.setContextObject(objectModel, JavaScriptFlowHelper.unwrap(viewData));
Source src = null;
try {
src = this.resolver.resolveURI("cocoon:/" + uri);
SourceUtil.toSAX(src, handler);
} finally {
FlowHelper.setContextObject(objectModel, oldViewData);
if (src != null) {
this.resolver.release(src);
}
}
}
/**
* Process a pipeline and gets is result as a DOM <code>Document</code>
*
* @param uri the pipeline URI
* @param viewData the view data object
* @return the document
*/
public Document processToDOM(String uri, Object viewData) throws ProcessingException, SAXException, IOException {
checkSetup();
Map objectModel = ContextHelper.getObjectModel(this.context);
Object oldViewData = FlowHelper.getContextObject(objectModel);
FlowHelper.setContextObject(objectModel, JavaScriptFlowHelper.unwrap(viewData));
Source src = null;
try {
src = this.resolver.resolveURI("cocoon:/" + uri);
return SourceUtil.toDOM(src);
} finally {
FlowHelper.setContextObject(objectModel, oldViewData);
if (src != null) {
this.resolver.release(src);
}
}
}
}