/*******************************************************************************
* Copyright (c) 2006, 2007 IBM Corporation and others.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* IBM Corporation - initial API and implementation
*******************************************************************************/
package org.eclipse.help.internal.dynamic;
import java.io.IOException;
import java.io.InputStream;
import javax.xml.parsers.ParserConfigurationException;
import org.eclipse.help.HelpSystem;
import org.eclipse.help.IUAElement;
import org.eclipse.help.internal.UAElement;
import org.xml.sax.SAXException;
/*
* Resolves includes by parsing the target document, extracting the node and
* replacing the original include with it.
*/
public class IncludeResolver {
private static final String ATTRIBUTE_ID = "id"; //$NON-NLS-1$
private DocumentProcessor processor;
private DocumentReader reader;
private String locale;
public IncludeResolver(DocumentProcessor processor, DocumentReader reader, String locale) {
this.processor = processor;
this.reader = reader;
this.locale = locale;
}
/*
* Resolves the include target to a processed Element.
*/
public UAElement resolve(String bundleId, String relativePath, String elementId) throws IOException, SAXException, ParserConfigurationException {
String href = '/' + bundleId + '/' + relativePath;
InputStream in = HelpSystem.getHelpContent(href, locale);
try {
UAElement element = findElement(in, elementId);
processor.process(element, href);
return element;
}
finally {
try {
in.close();
}
catch (IOException e) {}
}
}
/*
* Finds the specified element from the given XML input stream.
*/
private UAElement findElement(InputStream in, String elementId) throws IOException, SAXException, ParserConfigurationException {
UAElement element = reader.read(in);
return findElement(element, elementId);
}
/*
* Finds the specified element under the given subtree.
*/
private UAElement findElement(UAElement element, String elementId) {
String id = element.getAttribute(ATTRIBUTE_ID);
if (id != null && id.equals(elementId)) {
return element;
}
IUAElement[] children = element.getChildren();
for (int i=0;i<children.length;++i) {
UAElement result = findElement((UAElement)children[i], elementId);
if (result != null) {
return result;
}
}
return null;
}
}