/*
* 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.clerezza.platform.documentation;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.UnsupportedEncodingException;
import java.util.Iterator;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.transform.Result;
import javax.xml.transform.Source;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerException;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;
import javax.xml.transform.stream.StreamSource;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.apache.clerezza.rdf.core.NonLiteral;
import org.apache.clerezza.rdf.core.Resource;
import org.apache.clerezza.rdf.core.Triple;
import org.apache.clerezza.rdf.core.TypedLiteral;
import org.apache.clerezza.rdf.core.UriRef;
import org.apache.clerezza.rdf.core.impl.TripleImpl;
import org.apache.clerezza.rdf.core.impl.TypedLiteralImpl;
import org.w3c.dom.Document;
import org.xml.sax.SAXException;
/**
* Replaces the <code>BASE_URI_PLACEHOLDER</code> in the <code>UriRef</code>s
* as well as in the XML Literal of the <code>Triple</code>s provided by the
* specified <code>Iterator</code>s with the specified base URI.
*
* @author mir, hasan
*/
public class UriMutatorIterator implements Iterator<Triple> {
public static final Logger logger = LoggerFactory.getLogger(UriMutatorIterator.class);
private DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
public static final UriRef XML_LITERAL =
new UriRef("http://www.w3.org/1999/02/22-rdf-syntax-ns#XMLLiteral");
public static final String BASE_URI_PLACEHOLDER = "bundle://";
private Iterator<Triple> wrapped;
private String baseUri;
/*
* The symbolic name of the bundle from which the documentation origins.
*/
private String originBundleSymbName;
UriMutatorIterator(Iterator<Triple> wrapped, String baseUri,
String bundleSymbolicName) {
this.wrapped = wrapped;
this.baseUri = baseUri;
this.originBundleSymbName = bundleSymbolicName;
}
@Override
public boolean hasNext() {
return wrapped.hasNext();
}
@Override
public Triple next() {
Triple triple = wrapped.next();
NonLiteral subject = triple.getSubject();
if (subject instanceof UriRef) {
subject = replacePlaceHolder((UriRef) subject);
}
UriRef predicate = replacePlaceHolder(triple.getPredicate());
Resource object = triple.getObject();
if (object instanceof UriRef) {
object = replacePlaceHolder((UriRef) object);
} else if (object instanceof TypedLiteral) {
TypedLiteral literal = (TypedLiteral) object;
if (literal.getDataType().equals(XML_LITERAL)) {
object = replacePlaceHolderInUrl(literal);
}
}
return new TripleImpl(subject, predicate, object);
}
@Override
public void remove() {
throw new UnsupportedOperationException("Not supported.");
}
private UriRef replacePlaceHolder(UriRef uriRef) {
String orig = uriRef.getUnicodeString();
if (orig.startsWith(BASE_URI_PLACEHOLDER)) {
int nextSlash = orig.indexOf("/", BASE_URI_PLACEHOLDER.length());
String bundleSymbolicName;
if (nextSlash != BASE_URI_PLACEHOLDER.length()) {
bundleSymbolicName = orig.subSequence(
BASE_URI_PLACEHOLDER.length(), nextSlash).toString();
} else {
bundleSymbolicName = originBundleSymbName;
}
return new UriRef(baseUri + "bundle-doc/" + bundleSymbolicName +
orig.substring(nextSlash));
}
return uriRef;
}
private TypedLiteral replacePlaceHolderInUrl(TypedLiteral xmlLiteral) {
final String tagName = "infoBit";
final String openingTag = "<" + tagName + ">";
final String closingTag = "</" + tagName + ">";
String text = openingTag + xmlLiteral.getLexicalForm() + closingTag;
InputStream styleSheet = getClass().getResourceAsStream("baseUriTransformation.xsl");
TransformerFactory transformerFactory = TransformerFactory.newInstance();
StreamSource styleSource = new StreamSource(styleSheet);
try {
Transformer transformer = transformerFactory.newTransformer(styleSource);
DocumentBuilder builder = factory.newDocumentBuilder();
Document document = builder.parse(new ByteArrayInputStream(text.getBytes("UTF-8")));
Source source = new DOMSource(document);
ByteArrayOutputStream baos = new ByteArrayOutputStream(text.length());
Result result = new StreamResult(baos);
transformer.setParameter("baseUri", baseUri);
transformer.setParameter("originBundleSymbolicName", originBundleSymbName);
transformer.transform(source, result);
String resultedText = baos.toString("UTF-8");
int startIdx = resultedText.indexOf(openingTag) + openingTag.length();
int endIdx = resultedText.lastIndexOf(closingTag);
return new TypedLiteralImpl(resultedText.substring(startIdx, endIdx),
XML_LITERAL);
} catch (SAXException se) {
logger.warn("SAXException {} while transforming xml literal: {}",
se.getMessage(), text);
} catch (ParserConfigurationException pce) {
logger.warn("ParserConfigurationException {} while transforming xml literal: {}",
pce.getMessage(), text);
} catch (TransformerException te) {
logger.warn("TransformerException {} while transforming xml literal: {}",
te.getMessage(), text);
} catch (UnsupportedEncodingException uee) {
logger.warn("UnsupportedEncodingException {} while transforming xml literal: {}",
uee.getMessage(), text);
} catch (IOException ioe) {
logger.warn("IOException {} while transforming xml literal: {}",
ioe.getMessage(), text);
}
return xmlLiteral;
}
}