/*
* 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.jackrabbit.core.xml;
import java.util.Map;
import javax.jcr.RepositoryException;
import javax.jcr.Session;
import javax.jcr.ValueFactory;
import org.apache.jackrabbit.commons.NamespaceHelper;
import org.apache.jackrabbit.spi.Name;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.xml.sax.Attributes;
import org.xml.sax.Locator;
import org.xml.sax.SAXException;
import org.xml.sax.SAXParseException;
import org.xml.sax.helpers.DefaultHandler;
/**
* An <code>ImportHandler</code> instance can be used to import serialized
* data in System View XML or Document View XML. Processing of the XML is
* handled by specialized <code>ContentHandler</code>s
* (i.e. <code>SysViewImportHandler</code> and <code>DocViewImportHandler</code>).
* <p/>
* The actual task of importing though is delegated to the implementation of
* the <code>{@link Importer}</code> interface.
* <p/>
* <b>Important Note:</b>
* <p/>
* These SAX Event Handlers expect that Namespace URI's and local names are
* reported in the <code>start/endElement</code> events and that
* <code>start/endPrefixMapping</code> events are reported
* (i.e. default SAX2 Namespace processing).
*/
public class ImportHandler extends DefaultHandler {
private static Logger log = LoggerFactory.getLogger(ImportHandler.class);
protected final Importer importer;
private final NamespaceHelper helper;
private final ValueFactory valueFactory;
protected Locator locator;
private TargetImportHandler targetHandler = null;
/**
* The local namespace mappings reported by
* {@link #startPrefixMapping(String, String)}. These mappings are used
* to instantiate the local namespace context in
* {@link #startElement(String, String, String, Attributes)}.
*/
private Map<String, String> localNamespaceMappings;
public ImportHandler(Importer importer, Session session)
throws RepositoryException {
this.importer = importer;
this.helper = new NamespaceHelper(session);
this.localNamespaceMappings = helper.getNamespaces();
this.valueFactory = session.getValueFactory();
}
//---------------------------------------------------------< ErrorHandler >
/**
* {@inheritDoc}
*/
@Override
public void warning(SAXParseException e) throws SAXException {
// log exception and carry on...
log.warn("warning encountered at line: " + e.getLineNumber()
+ ", column: " + e.getColumnNumber()
+ " while parsing XML stream", e);
}
/**
* {@inheritDoc}
*/
@Override
public void error(SAXParseException e) throws SAXException {
// log exception and carry on...
log.error("error encountered at line: " + e.getLineNumber()
+ ", column: " + e.getColumnNumber()
+ " while parsing XML stream: " + e.toString());
}
/**
* {@inheritDoc}
*/
@Override
public void fatalError(SAXParseException e) throws SAXException {
// log and re-throw exception
log.error("fatal error encountered at line: " + e.getLineNumber()
+ ", column: " + e.getColumnNumber()
+ " while parsing XML stream: " + e.toString());
throw e;
}
//-------------------------------------------------------< ContentHandler >
/**
* {@inheritDoc}
*/
@Override
public void endDocument() throws SAXException {
// delegate to target handler
if (targetHandler != null) {
targetHandler.endDocument();
}
}
/**
* Records the given namespace mapping to be included in the local
* namespace context. The local namespace context is instantiated
* in {@link #startElement(String, String, String, Attributes)} using
* all the the namespace mappings recorded for the current XML element.
* <p>
* The namespace is also recorded in the persistent namespace registry
* unless it is already known.
*
* @param prefix namespace prefix
* @param uri namespace URI
*/
@Override
public void startPrefixMapping(String prefix, String uri)
throws SAXException {
localNamespaceMappings.put(prefix, uri);
try {
helper.registerNamespace(prefix, uri);
} catch (RepositoryException re) {
throw new SAXException(re);
}
}
/**
* {@inheritDoc}
*/
@Override
public void startElement(String namespaceURI, String localName, String qName,
Attributes atts) throws SAXException {
if (targetHandler == null) {
// the namespace of the first element determines the type of XML
// (system view/document view)
if (Name.NS_SV_URI.equals(namespaceURI)) {
targetHandler = new SysViewImportHandler(importer, valueFactory);
} else {
targetHandler = new DocViewImportHandler(importer, valueFactory);
}
targetHandler.startDocument();
}
// Start a namespace context for this element
targetHandler.startNamespaceContext(localNamespaceMappings);
localNamespaceMappings.clear();
// delegate to target handler
targetHandler.startElement(namespaceURI, localName, qName, atts);
}
/**
* {@inheritDoc}
*/
@Override
public void characters(char[] ch, int start, int length) throws SAXException {
// delegate to target handler
targetHandler.characters(ch, start, length);
}
/**
* Delegates the call to the underlying target handler and asks the
* handler to end the current namespace context.
* {@inheritDoc}
*/
@Override
public void endElement(String namespaceURI, String localName, String qName)
throws SAXException {
targetHandler.endElement(namespaceURI, localName, qName);
targetHandler.endNamespaceContext();
}
/**
* {@inheritDoc}
*/
@Override
public void setDocumentLocator(Locator locator) {
this.locator = locator;
}
}