/**
* Copyright 2011 meltmedia
*
* 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.xchain.framework.sax;
import org.xml.sax.helpers.DefaultHandler;
import org.xml.sax.Attributes;
import org.xml.sax.helpers.AttributesImpl;
import org.xml.sax.ext.LexicalHandler;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Set;
/**
* The SaxEventRecorder is a DefaultHandler implementation that will simply record all incoming SAX events. The events are stored as SaxEvent objects.
* The EventList is in the same order as the original SAX events. By default no SAX events are tracked. Types of event tracking can be enabled with {@link #setTrackDocumentEvents(boolean)},
* {@link #setTrackElementEvents(boolean)}, {@link #setTrackCharactersEvents(boolean)}, and {@link #setTrackPrefixMappingEvents(boolean)}.
*
* @author Christian Trimble
* @author Devon Tackett
*/
public class SaxEventRecorder
extends DefaultHandler
implements LexicalHandler
{
/** The list of recorded SAX events. */
protected List<SaxEvent> eventList = new ArrayList<SaxEvent>();
/** Whether document events should be tracked. */
protected boolean trackDocumentEvents = false;
/** Whether element events should be tracked. */
protected boolean trackElementEvents = false;
/** Whether character events should be tracked. */
protected boolean trackCharactersEvents = false;
/** Whether prefix mapping events should be tracked. */
protected boolean trackPrefixMappingEvents = false;
/** Whether comment events should be tracked. */
protected boolean trackCommentEvents = false;
/**
* @return The recorded list of SAX events.
*/
public List<SaxEvent> getEventList() { return eventList; }
/**
* Set whether document SAX events should be tracked.
*/
public void setTrackDocumentEvents( boolean trackDocumentEvents ) { this.trackDocumentEvents = trackDocumentEvents; }
/**
* Set whether element SAX events should be tracked.
*/
public void setTrackElementEvents( boolean trackElementEvents ) { this.trackElementEvents = trackElementEvents; }
/**
* Set whether character SAX events should be tracked.
*/
public void setTrackCharactersEvents( boolean trackCharactersEvents ) { this.trackCharactersEvents = trackCharactersEvents; }
/**
* Set whether prefix mapping events should be tracked.
*/
public void setTrackPrefixMappingEvents( boolean trackPrefixMappingEvents ) { this.trackPrefixMappingEvents = trackPrefixMappingEvents; }
public void setTrackCommentEvents( boolean trackCommentEvents ) { this.trackCommentEvents = trackCommentEvents; }
public void startDocument()
{
if( trackDocumentEvents ) {
SaxEvent saxEvent = new SaxEvent();
saxEvent.setType(EventType.START_DOCUMENT);
eventList.add(saxEvent);
}
}
public void endDocument()
{
if( trackDocumentEvents ) {
SaxEvent saxEvent = new SaxEvent();
saxEvent.setType(EventType.END_DOCUMENT);
eventList.add(saxEvent);
}
}
public void startElement( String uri, String localName, String qName, Attributes attributes )
{
if( trackElementEvents ) {
SaxEvent saxEvent = new SaxEvent();
saxEvent.setType(EventType.START_ELEMENT);
saxEvent.setUri(uri);
saxEvent.setLocalName(localName);
saxEvent.setQName(qName);
saxEvent.setAttributes(new AttributesImpl(attributes));
eventList.add(saxEvent);
}
}
public void endElement( String uri, String localName, String qName )
{
if( trackElementEvents ) {
SaxEvent saxEvent = new SaxEvent();
saxEvent.setType(EventType.END_ELEMENT);
saxEvent.setUri(uri);
saxEvent.setLocalName(localName);
eventList.add(saxEvent);
}
}
public void characters( char[] characters, int start, int length )
{
if( trackCharactersEvents ) {
// if the previous event was characters, then append.
if( !eventList.isEmpty() && eventList.get(eventList.size()-1).getType() == EventType.CHARACTERS ) {
SaxEvent saxEvent = eventList.get(eventList.size()-1);
saxEvent.setText(new StringBuilder().append(saxEvent.getText()).append( characters, start, length ).toString());
}
else {
SaxEvent saxEvent = new SaxEvent();
saxEvent.setType(EventType.CHARACTERS);
saxEvent.setText(new StringBuilder().append( characters, start, length ).toString());
eventList.add(saxEvent);
}
}
}
public void startPrefixMapping( String prefix, String uri )
{
if( trackPrefixMappingEvents ) {
if( !eventList.isEmpty() && eventList.get(eventList.size()-1).getType() == EventType.START_PREFIX_MAPPING ) {
eventList.get(eventList.size()-1).getPrefixMapping().put(prefix, uri);
}
else {
SaxEvent saxEvent = new SaxEvent();
saxEvent.setType(EventType.START_PREFIX_MAPPING);
HashMap<String, String> prefixMapping = new HashMap<String, String>();
prefixMapping.put(prefix, uri);
saxEvent.setPrefixMapping(prefixMapping);
eventList.add(saxEvent);
}
}
}
public void endPrefixMapping( String prefix )
{
if( trackPrefixMappingEvents ) {
if( !eventList.isEmpty() && eventList.get(eventList.size()-1).getType() == EventType.END_PREFIX_MAPPING ) {
eventList.get(eventList.size()-1).getPrefixSet().add(prefix);
}
else {
SaxEvent saxEvent = new SaxEvent();
saxEvent.setType(EventType.END_PREFIX_MAPPING);
Set<String> prefixSet = new HashSet<String>();
prefixSet.add(prefix);
saxEvent.setPrefixSet(prefixSet);
eventList.add(saxEvent);
}
}
}
public void comment( char[] comment, int start, int length )
{
if( trackCommentEvents ) {
SaxEvent saxEvent = new SaxEvent();
saxEvent.setType(EventType.COMMENT);
saxEvent.setText(new StringBuilder().append( comment, start, length ).toString());
eventList.add(saxEvent);
}
}
public void startDTD( String name, String publicId, String systemId ) { }
public void endDTD() { }
public void startCDATA() { }
public void endCDATA() { }
public void startEntity( String name ) { }
public void endEntity( String name ) { }
public String toString()
{
StringBuilder sb = new StringBuilder();
for( SaxEvent event : eventList ) {
sb.append(event.toString()).append("\n");
}
return sb.toString();
}
public static enum EventType
{
START_DOCUMENT,
END_DOCUMENT,
START_PREFIX_MAPPING,
END_PREFIX_MAPPING,
START_ELEMENT,
END_ELEMENT,
CHARACTERS,
COMMENT
}
/**
* This class represents a recorded SAX event.
*/
public static class SaxEvent
{
private EventType type;
private String text;
private String uri;
private String localName;
private String qName;
private Attributes attributes;
private Map<String, String> prefixMapping;
private Set<String> prefixSet;
public EventType getType() { return this.type; }
public void setType( EventType type ) { this.type = type; }
public String getText() { return this.text; }
public void setText( String text ) { this.text = text; }
public String getUri() { return uri; }
public void setUri( String uri ) { this.uri = uri; }
public String getLocalName() { return localName; }
public void setLocalName( String localName ) { this.localName = localName; }
public String getQName() { return qName; }
public void setQName( String qName ) { this.qName = qName; }
public Map<String, String> getPrefixMapping() { return this.prefixMapping; }
public void setPrefixMapping( Map<String, String> prefixMapping ) { this.prefixMapping = prefixMapping; }
public Set<String> getPrefixSet() { return this.prefixSet; }
public void setPrefixSet( Set<String> prefixSet ) { this.prefixSet = prefixSet; }
public Attributes getAttributes() { return this.attributes; }
public void setAttributes( Attributes attributes ) { this.attributes = attributes; }
public String toString() {
StringBuilder sb = new StringBuilder();
sb.append(" ").append(type).append("\n");
if( uri != null ) {
sb.append(" ").append("uri:").append(uri).append("\n");
}
if( localName != null ) {
sb.append(" ").append("localName:").append(localName).append("\n");
}
if( prefixMapping != null ) {
for( Map.Entry<String, String> entry : prefixMapping.entrySet() ) {
sb.append(" ").append("prefix:").append(entry.getKey()).append(" namespace:").append(entry.getValue()).append("\n");
}
}
return sb.toString();
}
}
}