org.dom4j.io.SAXEventRecorder Maven / Gradle / Ivy
/*
* Copyright 2001-2005 (C) MetaStuff, Ltd. All Rights Reserved.
*
* This software is open source.
* See the bottom of this file for the licence.
*/
package org.dom4j.io;
import java.io.Externalizable;
import java.io.IOException;
import java.io.ObjectInput;
import java.io.ObjectOutput;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import org.dom4j.Namespace;
import org.dom4j.QName;
import org.xml.sax.Attributes;
import org.xml.sax.ContentHandler;
import org.xml.sax.DTDHandler;
import org.xml.sax.SAXException;
import org.xml.sax.ext.DeclHandler;
import org.xml.sax.ext.LexicalHandler;
import org.xml.sax.helpers.AttributesImpl;
import org.xml.sax.helpers.DefaultHandler;
/**
*
* Records SAX events such that they may be "replayed" at a later time. Provides
* an alternative serialization approach when externalizing a DOM4J document.
* Rather than serializing a document as text and re-parsing, the sax events may
* be serialized instead.
*
* Example usage:
*
*
*
*
*
* SAXEventRecorder recorder = new SAXEventRecorder();
* SAXWriter saxWriter = new SAXWriter(recorder, recorder);
* saxWriter.write(document);
* out.writeObject(recorder);
* ...
* SAXEventRecorder recorder = (SAXEventRecorder)in.readObject();
* SAXContentHandler saxContentHandler = new SAXContentHandler();
* recorder.replay(saxContentHandler);
* Document document = saxContentHandler.getDocument();
*
*
*
*
*
* @author Todd Wolff (Bluestem Software)
*/
public class SAXEventRecorder extends DefaultHandler implements LexicalHandler,
DeclHandler, DTDHandler, Externalizable {
public static final long serialVersionUID = 1;
// private static final byte STRING = 0;
private static final byte OBJECT = 1;
private static final byte NULL = 2;
private List events = new ArrayList();
private Map> prefixMappings = new HashMap>();
private static final String XMLNS = "xmlns";
private static final String EMPTY_STRING = "";
public SAXEventRecorder() {
}
public void replay(ContentHandler handler) throws SAXException {
for (SAXEvent saxEvent : events) {
switch (saxEvent.event) {
// replay to ContentHandler
case SAXEvent.PROCESSING_INSTRUCTION:
handler.processingInstruction((String) saxEvent.getParm(0),
(String) saxEvent.getParm(1));
break;
case SAXEvent.START_PREFIX_MAPPING:
handler.startPrefixMapping((String) saxEvent.getParm(0),
(String) saxEvent.getParm(1));
break;
case SAXEvent.END_PREFIX_MAPPING:
handler.endPrefixMapping((String) saxEvent.getParm(0));
break;
case SAXEvent.START_DOCUMENT:
handler.startDocument();
break;
case SAXEvent.END_DOCUMENT:
handler.endDocument();
break;
case SAXEvent.START_ELEMENT:
AttributesImpl attributes = new AttributesImpl();
@SuppressWarnings("unchecked") List attParmList = (List) saxEvent.getParm(3);
if (attParmList != null) {
for (String[] attParms : attParmList) {
attributes.addAttribute(attParms[0], attParms[1],
attParms[2], attParms[3], attParms[4]);
}
}
handler.startElement((String) saxEvent.getParm(0),
(String) saxEvent.getParm(1), (String) saxEvent
.getParm(2), attributes);
break;
case SAXEvent.END_ELEMENT:
handler.endElement((String) saxEvent.getParm(0),
(String) saxEvent.getParm(1), (String) saxEvent
.getParm(2));
break;
case SAXEvent.CHARACTERS:
char[] chars = (char[]) saxEvent.getParm(0);
int start = (Integer) saxEvent.getParm(1);
int end = (Integer) saxEvent.getParm(2);
handler.characters(chars, start, end);
break;
// replay to LexicalHandler
case SAXEvent.START_DTD:
((LexicalHandler) handler).startDTD((String) saxEvent
.getParm(0), (String) saxEvent.getParm(1),
(String) saxEvent.getParm(2));
break;
case SAXEvent.END_DTD:
((LexicalHandler) handler).endDTD();
break;
case SAXEvent.START_ENTITY:
((LexicalHandler) handler).startEntity((String) saxEvent
.getParm(0));
break;
case SAXEvent.END_ENTITY:
((LexicalHandler) handler).endEntity((String) saxEvent
.getParm(0));
break;
case SAXEvent.START_CDATA:
((LexicalHandler) handler).startCDATA();
break;
case SAXEvent.END_CDATA:
((LexicalHandler) handler).endCDATA();
break;
case SAXEvent.COMMENT:
char[] cchars = (char[]) saxEvent.getParm(0);
int cstart = (Integer) saxEvent.getParm(1);
int cend = (Integer) saxEvent.getParm(2);
((LexicalHandler) handler).comment(cchars, cstart, cend);
break;
// replay to DeclHandler
case SAXEvent.ELEMENT_DECL:
((DeclHandler) handler).elementDecl((String) saxEvent
.getParm(0), (String) saxEvent.getParm(1));
break;
case SAXEvent.ATTRIBUTE_DECL:
((DeclHandler) handler).attributeDecl((String) saxEvent
.getParm(0), (String) saxEvent.getParm(1),
(String) saxEvent.getParm(2), (String) saxEvent
.getParm(3), (String) saxEvent.getParm(4));
break;
case SAXEvent.INTERNAL_ENTITY_DECL:
((DeclHandler) handler).internalEntityDecl(
(String) saxEvent.getParm(0), (String) saxEvent
.getParm(1));
break;
case SAXEvent.EXTERNAL_ENTITY_DECL:
((DeclHandler) handler).externalEntityDecl(
(String) saxEvent.getParm(0), (String) saxEvent
.getParm(1), (String) saxEvent.getParm(2));
break;
default:
throw new SAXException("Unrecognized event: "
+ saxEvent.event);
}
}
}
// ContentHandler interface
// -------------------------------------------------------------------------
public void processingInstruction(String target, String data)
throws SAXException {
SAXEvent saxEvent = new SAXEvent(SAXEvent.PROCESSING_INSTRUCTION);
saxEvent.addParm(target);
saxEvent.addParm(data);
events.add(saxEvent);
}
public void startPrefixMapping(String prefix, String uri)
throws SAXException {
SAXEvent saxEvent = new SAXEvent(SAXEvent.START_PREFIX_MAPPING);
saxEvent.addParm(prefix);
saxEvent.addParm(uri);
events.add(saxEvent);
}
public void endPrefixMapping(String prefix) throws SAXException {
SAXEvent saxEvent = new SAXEvent(SAXEvent.END_PREFIX_MAPPING);
saxEvent.addParm(prefix);
events.add(saxEvent);
}
public void startDocument() throws SAXException {
SAXEvent saxEvent = new SAXEvent(SAXEvent.START_DOCUMENT);
events.add(saxEvent);
}
public void endDocument() throws SAXException {
SAXEvent saxEvent = new SAXEvent(SAXEvent.END_DOCUMENT);
events.add(saxEvent);
}
public void startElement(String namespaceURI, String localName,
String qualifiedName, Attributes attributes) throws SAXException {
SAXEvent saxEvent = new SAXEvent(SAXEvent.START_ELEMENT);
saxEvent.addParm(namespaceURI);
saxEvent.addParm(localName);
saxEvent.addParm(qualifiedName);
QName qName;
if (namespaceURI != null) {
qName = new QName(localName, Namespace.get(namespaceURI));
} else {
qName = new QName(localName);
}
if ((attributes != null) && (attributes.getLength() > 0)) {
List attParmList = new ArrayList(attributes.getLength());
String[] attParms;
for (int i = 0; i < attributes.getLength(); i++) {
String attLocalName = attributes.getLocalName(i);
if (attLocalName.startsWith(XMLNS)) {
// if SAXWriter is writing a DOMDocument, namespace
// decls are treated as attributes. record a start
// prefix mapping event
String prefix;
if (attLocalName.length() > 5) {
prefix = attLocalName.substring(6);
} else {
prefix = EMPTY_STRING;
}
SAXEvent prefixEvent = new SAXEvent(
SAXEvent.START_PREFIX_MAPPING);
prefixEvent.addParm(prefix);
prefixEvent.addParm(attributes.getValue(i));
events.add(prefixEvent);
// 'register' the prefix so that we can generate
// an end prefix mapping event within endElement
List prefixes = prefixMappings.get(qName);
if (prefixes == null) {
prefixes = new ArrayList();
prefixMappings.put(qName, prefixes);
}
prefixes.add(prefix);
} else {
attParms = new String[5];
attParms[0] = attributes.getURI(i);
attParms[1] = attLocalName;
attParms[2] = attributes.getQName(i);
attParms[3] = attributes.getType(i);
attParms[4] = attributes.getValue(i);
attParmList.add(attParms);
}
}
saxEvent.addParm(attParmList);
}
events.add(saxEvent);
}
public void endElement(String namespaceURI, String localName, String qName)
throws SAXException {
SAXEvent saxEvent = new SAXEvent(SAXEvent.END_ELEMENT);
saxEvent.addParm(namespaceURI);
saxEvent.addParm(localName);
saxEvent.addParm(qName);
events.add(saxEvent);
// check to see if a we issued a start prefix mapping event
// for DOMDocument namespace decls
QName elementName;
if (namespaceURI != null) {
elementName = new QName(localName, Namespace.get(namespaceURI));
} else {
elementName = new QName(localName);
}
List prefixes = prefixMappings.get(elementName);
if (prefixes != null) {
for (String prefixe : prefixes) {
SAXEvent prefixEvent =
new SAXEvent(SAXEvent.END_PREFIX_MAPPING);
prefixEvent.addParm(prefixe);
events.add(prefixEvent);
}
}
}
public void characters(char[] ch, int start, int end) throws SAXException {
SAXEvent saxEvent = new SAXEvent(SAXEvent.CHARACTERS);
saxEvent.addParm(ch);
saxEvent.addParm(start);
saxEvent.addParm(end);
events.add(saxEvent);
}
// LexicalHandler interface
// -------------------------------------------------------------------------
public void startDTD(String name, String publicId, String systemId)
throws SAXException {
SAXEvent saxEvent = new SAXEvent(SAXEvent.START_DTD);
saxEvent.addParm(name);
saxEvent.addParm(publicId);
saxEvent.addParm(systemId);
events.add(saxEvent);
}
public void endDTD() throws SAXException {
SAXEvent saxEvent = new SAXEvent(SAXEvent.END_DTD);
events.add(saxEvent);
}
public void startEntity(String name) throws SAXException {
SAXEvent saxEvent = new SAXEvent(SAXEvent.START_ENTITY);
saxEvent.addParm(name);
events.add(saxEvent);
}
public void endEntity(String name) throws SAXException {
SAXEvent saxEvent = new SAXEvent(SAXEvent.END_ENTITY);
saxEvent.addParm(name);
events.add(saxEvent);
}
public void startCDATA() throws SAXException {
SAXEvent saxEvent = new SAXEvent(SAXEvent.START_CDATA);
events.add(saxEvent);
}
public void endCDATA() throws SAXException {
SAXEvent saxEvent = new SAXEvent(SAXEvent.END_CDATA);
events.add(saxEvent);
}
public void comment(char[] ch, int start, int end) throws SAXException {
SAXEvent saxEvent = new SAXEvent(SAXEvent.COMMENT);
saxEvent.addParm(ch);
saxEvent.addParm(start);
saxEvent.addParm(end);
events.add(saxEvent);
}
// DeclHandler interface
// -------------------------------------------------------------------------
public void elementDecl(String name, String model) throws SAXException {
SAXEvent saxEvent = new SAXEvent(SAXEvent.ELEMENT_DECL);
saxEvent.addParm(name);
saxEvent.addParm(model);
events.add(saxEvent);
}
public void attributeDecl(String eName, String aName, String type,
String valueDefault, String value) throws SAXException {
SAXEvent saxEvent = new SAXEvent(SAXEvent.ATTRIBUTE_DECL);
saxEvent.addParm(eName);
saxEvent.addParm(aName);
saxEvent.addParm(type);
saxEvent.addParm(valueDefault);
saxEvent.addParm(value);
events.add(saxEvent);
}
public void internalEntityDecl(String name, String value)
throws SAXException {
SAXEvent saxEvent = new SAXEvent(SAXEvent.INTERNAL_ENTITY_DECL);
saxEvent.addParm(name);
saxEvent.addParm(value);
events.add(saxEvent);
}
public void externalEntityDecl(String name, String publicId, String sysId)
throws SAXException {
SAXEvent saxEvent = new SAXEvent(SAXEvent.EXTERNAL_ENTITY_DECL);
saxEvent.addParm(name);
saxEvent.addParm(publicId);
saxEvent.addParm(sysId);
events.add(saxEvent);
}
public void writeExternal(ObjectOutput out) throws IOException {
if (events == null) {
out.writeByte(NULL);
} else {
out.writeByte(OBJECT);
out.writeObject(events);
}
}
@SuppressWarnings("unchecked")
public void readExternal(ObjectInput in) throws ClassNotFoundException,
IOException {
if (in.readByte() != NULL) {
events = (List) in.readObject();
}
}
// SAXEvent inner class
// -------------------------------------------------------------------------
static class SAXEvent implements Externalizable {
public static final long serialVersionUID = 1;
static final byte PROCESSING_INSTRUCTION = 1;
static final byte START_PREFIX_MAPPING = 2;
static final byte END_PREFIX_MAPPING = 3;
static final byte START_DOCUMENT = 4;
static final byte END_DOCUMENT = 5;
static final byte START_ELEMENT = 6;
static final byte END_ELEMENT = 7;
static final byte CHARACTERS = 8;
static final byte START_DTD = 9;
static final byte END_DTD = 10;
static final byte START_ENTITY = 11;
static final byte END_ENTITY = 12;
static final byte START_CDATA = 13;
static final byte END_CDATA = 14;
static final byte COMMENT = 15;
static final byte ELEMENT_DECL = 16;
static final byte ATTRIBUTE_DECL = 17;
static final byte INTERNAL_ENTITY_DECL = 18;
static final byte EXTERNAL_ENTITY_DECL = 19;
protected byte event;
protected List