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////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
// Copyright (c) 2015 Saxonica Limited.
// This Source Code Form is subject to the terms of the Mozilla Public License, v. 2.0.
// If a copy of the MPL was not distributed with this file, You can obtain one at http://mozilla.org/MPL/2.0/.
// This Source Code Form is "Incompatible With Secondary Licenses", as defined by the Mozilla Public License, v. 2.0.
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
package net.sf.saxon.evpull;
import net.sf.saxon.Configuration;
import net.sf.saxon.event.NamespaceReducer;
import net.sf.saxon.event.PipelineConfiguration;
import net.sf.saxon.expr.parser.ExplicitLocation;
import net.sf.saxon.om.FingerprintedQName;
import net.sf.saxon.om.NamePool;
import net.sf.saxon.om.NoNamespaceName;
import net.sf.saxon.pull.UnparsedEntity;
import net.sf.saxon.serialize.XMLEmitter;
import net.sf.saxon.trans.SaxonErrorCode;
import net.sf.saxon.trans.XPathException;
import net.sf.saxon.tree.tiny.CharSlice;
import net.sf.saxon.tree.util.Orphan;
import net.sf.saxon.type.Type;
import net.sf.saxon.type.Untyped;
import net.sf.saxon.value.Whitespace;
import javax.xml.stream.*;
import javax.xml.stream.events.EntityDeclaration;
import javax.xml.transform.SourceLocator;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.net.URI;
import java.net.URISyntaxException;
import java.util.ArrayList;
import java.util.List;
import java.util.Properties;
/**
* This class implements the Saxon EventIterator API on top of a standard StAX parser
* (or any other StAX XMLStreamReader implementation)
*/
public class StaxToEventBridge implements EventIterator, SourceLocator {
private Configuration config;
private XMLStreamReader reader;
private PipelineConfiguration pipe;
/*@Nullable*/ private List unparsedEntities = null;
PullEvent currentEvent = null;
int depth = 0;
boolean ignoreIgnorable = false;
/**
* Create a new instance of the class
*/
public StaxToEventBridge() {
}
/**
* Supply an input stream containing XML to be parsed. A StAX parser is created using
* the JAXP XMLInputFactory.
*
* @param systemId The Base URI of the input document
* @param inputStream the stream containing the XML to be parsed
* @throws net.sf.saxon.trans.XPathException
* if an error occurs creating the StAX parser
*/
public void setInputStream(String systemId, InputStream inputStream) throws XPathException {
try {
XMLInputFactory factory = XMLInputFactory.newInstance();
//XMLInputFactory factory = new WstxInputFactory();
factory.setXMLReporter(new StaxErrorReporter());
reader = factory.createXMLStreamReader(systemId, inputStream);
} catch (XMLStreamException e) {
throw new XPathException(e);
}
}
/**
* Supply an XMLStreamReader: the events reported by this XMLStreamReader will be translated
* into EventIterator events
*
* @param reader the supplier of XML events, typically an XML parser
*/
public void setXMLStreamReader(XMLStreamReader reader) {
this.reader = reader;
}
/**
* Set configuration information. This must only be called before any events
* have been read.
*
* @param pipe the pipeline configuration
*/
public void setPipelineConfiguration(PipelineConfiguration pipe) {
this.pipe = new PipelineConfiguration(pipe);
config = pipe.getConfiguration();
ignoreIgnorable = config.getStripsWhiteSpace() != Whitespace.NONE;
}
/**
* Get configuration information.
*
* @return the pipeline configuration
*/
public PipelineConfiguration getPipelineConfiguration() {
return pipe;
}
/**
* Get the XMLStreamReader used by this StaxBridge. This is available only after
* setInputStream() or setXMLStreamReader() has been called
*
* @return the instance of XMLStreamReader allocated when setInputStream() was called,
* or the instance supplied directly to setXMLStreamReader()
*/
public XMLStreamReader getXMLStreamReader() {
return reader;
}
/**
* Get the name pool
*
* @return the name pool
*/
public NamePool getNamePool() {
return pipe.getConfiguration().getNamePool();
}
/**
* Get the next event
*
* @return the next event; or null to indicate the end of the event stream
*/
public PullEvent next() throws XPathException {
if (currentEvent == null) {
// StAX isn't reporting START_DOCUMENT so we supply it ourselves
currentEvent = StartDocumentEvent.getInstance();
return currentEvent;
}
if (currentEvent instanceof EndDocumentEvent) {
try {
reader.close();
} catch (XMLStreamException e) {
//
}
return null;
}
try {
if (reader.hasNext()) {
int event = reader.next();
//System.err.println("Read event " + event);
currentEvent = translate(event);
} else {
currentEvent = null;
}
} catch (XMLStreamException e) {
String message = e.getMessage();
// Following code recognizes the messages produced by the Sun Zephyr parser
if (message.startsWith("ParseError at")) {
int c = message.indexOf("\nMessage: ");
if (c > 0) {
message = message.substring(c + 10);
}
}
XPathException err = new XPathException("Error reported by XML parser: " + message);
err.setErrorCode(SaxonErrorCode.SXXP0003);
err.setLocator(translateLocation(e.getLocation()));
throw err;
}
return currentEvent;
}
/**
* Translate a StAX event into a Saxon PullEvent
*
* @param event the StAX event
* @return the Saxon PullEvent
* @throws XPathException
*/
private PullEvent translate(int event) throws XPathException {
//System.err.println("EVENT " + event);
switch (event) {
case XMLStreamConstants.ATTRIBUTE:
return next(); // attributes are reported as part of StartElement
case XMLStreamConstants.CDATA:
case XMLStreamConstants.CHARACTERS:
if (depth == 0 && reader.isWhiteSpace()) {
return next();
} else {
Orphan o = new Orphan(config);
o.setNodeKind(Type.TEXT);
CharSlice value = new CharSlice(
reader.getTextCharacters(), reader.getTextStart(), reader.getTextLength());
o.setStringValue(value);
return o;
}
case XMLStreamConstants.COMMENT: {
Orphan o = new Orphan(config);
o.setNodeKind(Type.COMMENT);
CharSlice value = new CharSlice(
reader.getTextCharacters(), reader.getTextStart(), reader.getTextLength());
o.setStringValue(value);
return o;
}
case XMLStreamConstants.DTD:
unparsedEntities = (List) reader.getProperty("javax.xml.stream.entities");
return next();
case XMLStreamConstants.END_DOCUMENT:
return EndDocumentEvent.getInstance();
case XMLStreamConstants.END_ELEMENT:
depth--;
return EndElementEvent.getInstance();
case XMLStreamConstants.ENTITY_DECLARATION:
return next();
case XMLStreamConstants.ENTITY_REFERENCE:
return next();
case XMLStreamConstants.NAMESPACE:
return next(); // namespaces are reported as part of StartElement
case XMLStreamConstants.NOTATION_DECLARATION:
return next();
case XMLStreamConstants.PROCESSING_INSTRUCTION: {
Orphan o = new Orphan(config);
o.setNodeKind(Type.PROCESSING_INSTRUCTION);
String local = reader.getPITarget();
o.setNodeName(new NoNamespaceName(local));
o.setStringValue(reader.getText());
return o;
}
case XMLStreamConstants.SPACE:
if (depth == 0) {
return next();
} else if (ignoreIgnorable) {
// (Brave attempt, but Woodstox doesn't seem to report ignorable whitespace)
return next();
} else {
Orphan o = new Orphan(config);
o.setNodeKind(Type.TEXT);
o.setStringValue(reader.getText());
return o;
}
case XMLStreamConstants.START_DOCUMENT:
return next(); // we supplied the START_DOCUMENT ourselves
case XMLStreamConstants.START_ELEMENT:
depth++;
StartElementEvent see = new StartElementEvent(pipe);
String elocal = reader.getLocalName();
String euri = reader.getNamespaceURI();
String eprefix = reader.getPrefix();
if (eprefix == null) {
eprefix = "";
}
if (euri == null) {
euri = "";
}
see.setElementName(new FingerprintedQName(eprefix, euri, elocal));
see.setTypeCode(Untyped.getInstance());
int attCount = reader.getAttributeCount();
for (int index = 0; index < attCount; index++) {
String local = reader.getAttributeLocalName(index);
String uri = reader.getAttributeNamespace(index);
String prefix = reader.getAttributePrefix(index);
if (prefix == null) {
prefix = "";
}
if (uri == null) {
uri = "";
}
Orphan o = new Orphan(config);
o.setNodeKind(Type.ATTRIBUTE);
o.setNodeName(new FingerprintedQName(prefix, uri, local));
o.setStringValue(reader.getAttributeValue(index));
see.addAttribute(o);
}
see.namespaceFixup();
return see;
default:
throw new IllegalStateException("Unknown StAX event " + event);
}
}
/**
* Return the public identifier for the current document event.
*
* The return value is the public identifier of the document
* entity or of the external parsed entity in which the markup
* triggering the event appears.
*
* @return A string containing the public identifier, or
* null if none is available.
* @see #getSystemId
*/
public String getPublicId() {
return reader.getLocation().getPublicId();
}
/**
* Return the system identifier for the current document event.
*
* The return value is the system identifier of the document
* entity or of the external parsed entity in which the markup
* triggering the event appears.
*
* If the system identifier is a URL, the parser must resolve it
* fully before passing it to the application. For example, a file
* name must always be provided as a file:... URL, and other
* kinds of relative URI are also resolved against their bases.
*
* @return A string containing the system identifier, or null
* if none is available.
* @see #getPublicId
*/
public String getSystemId() {
return reader.getLocation().getSystemId();
}
/**
* Return the line number where the current document event ends.
* Lines are delimited by line ends, which are defined in
* the XML specification.
*
* Warning: The return value from the method
* is intended only as an approximation for the sake of diagnostics;
* it is not intended to provide sufficient information
* to edit the character content of the original XML document.
* In some cases, these "line" numbers match what would be displayed
* as columns, and in others they may not match the source text
* due to internal entity expansion.
*
* The return value is an approximation of the line number
* in the document entity or external parsed entity where the
* markup triggering the event appears.
*
* If possible, the SAX driver should provide the line position
* of the first character after the text associated with the document
* event. The first line is line 1.
*
* @return The line number, or -1 if none is available.
* @see #getColumnNumber
*/
public int getLineNumber() {
return reader.getLocation().getLineNumber();
}
/**
* Return the column number where the current document event ends.
* This is one-based number of Java char values since
* the last line end.
*
* Warning: The return value from the method
* is intended only as an approximation for the sake of diagnostics;
* it is not intended to provide sufficient information
* to edit the character content of the original XML document.
* For example, when lines contain combining character sequences, wide
* characters, surrogate pairs, or bi-directional text, the value may
* not correspond to the column in a text editor's display.
*
* The return value is an approximation of the column number
* in the document entity or external parsed entity where the
* markup triggering the event appears.
*
* If possible, the SAX driver should provide the line position
* of the first character after the text associated with the document
* event. The first column in each line is column 1.
*
* @return The column number, or -1 if none is available.
* @see #getLineNumber
*/
public int getColumnNumber() {
return reader.getLocation().getColumnNumber();
}
public String getSystemId(int locationId) {
return getSystemId();
}
public int getLineNumber(int locationId) {
return getLineNumber();
}
public int getColumnNumber(int locationId) {
return getColumnNumber();
}
/**
* Get a list of unparsed entities.
*
* @return a list of unparsed entities, or null if the information is not available, or
* an empty list if there are no unparsed entities. Each item in the list will
* be an instance of {@link net.sf.saxon.pull.UnparsedEntity}
*/
public List getUnparsedEntities() {
if (unparsedEntities == null) {
return null;
}
List list = new ArrayList(unparsedEntities.size());
for (int i = 0; i < unparsedEntities.size(); i++) {
Object ent = unparsedEntities.get(i);
String name = null;
String systemId = null;
String publicId = null;
String baseURI = null;
if (ent instanceof EntityDeclaration) {
// This is what we would expect from the StAX API spec
EntityDeclaration ed = (EntityDeclaration) ent;
name = ed.getName();
systemId = ed.getSystemId();
publicId = ed.getPublicId();
baseURI = ed.getBaseURI();
} else if (ent.getClass().getName().equals("com.ctc.wstx.ent.UnparsedExtEntity")) {
// Woodstox 3.0.0 returns this: use introspection to get the data we need
try {
Class woodstoxClass = ent.getClass();
Class[] noArgs = new Class[0];
Method method = woodstoxClass.getMethod("getName", noArgs);
name = (String) method.invoke(ent, (Object[]) noArgs);
method = woodstoxClass.getMethod("getSystemId", noArgs);
systemId = (String) method.invoke(ent, (Object[]) noArgs);
method = woodstoxClass.getMethod("getPublicId", noArgs);
publicId = (String) method.invoke(ent, (Object[]) noArgs);
method = woodstoxClass.getMethod("getBaseURI", noArgs);
baseURI = (String) method.invoke(ent, (Object[]) noArgs);
} catch (NoSuchMethodException e) {
//
} catch (IllegalAccessException e) {
//
} catch (InvocationTargetException e) {
//
}
}
if (name != null) {
try {
systemId = new URI(baseURI).resolve(systemId).toString();
} catch (URISyntaxException err) {
//
}
UnparsedEntity ue = new UnparsedEntity();
ue.setName(name);
ue.setSystemId(systemId);
ue.setPublicId(publicId);
ue.setBaseURI(baseURI);
list.add(ue);
}
}
return list;
}
/**
* Translate a StAX Location object to a Saxon Locator
*
* @param location the StAX Location object
* @return a Saxon/SAX SourceLocator object
*/
private ExplicitLocation translateLocation(Location location) {
if (location == null) {
return ExplicitLocation.UNKNOWN_LOCATION;
} else {
return new ExplicitLocation(location.getSystemId(), location.getLineNumber(), location.getColumnNumber());
}
}
/**
* Error reporting class for StAX parser errors
*/
private class StaxErrorReporter implements XMLReporter {
public void report(String message, String errorType,
Object relatedInformation, Location location)
throws XMLStreamException {
ExplicitLocation loc = translateLocation(location);
XPathException err = new XPathException("Error reported by XML parser: " + message + " (" + errorType + ')');
err.setLocator(loc);
pipe.getErrorListener().error(err);
}
}
/**
* Simple test program
* Usage: java StaxBridge in.xml [out.xml]
*
* @param args command line arguments
*/
public static void main(String[] args) throws Exception {
for (int i = 0; i < 1; i++) {
long startTime = System.currentTimeMillis();
PipelineConfiguration pipe = new Configuration().makePipelineConfiguration();
StaxToEventBridge puller = new StaxToEventBridge();
File f = new File(args[0]);
puller.setInputStream(f.toURI().toString(), new FileInputStream(f));
puller.setPipelineConfiguration(pipe);
XMLEmitter emitter = new XMLEmitter();
emitter.setPipelineConfiguration(pipe);
emitter.setOutputProperties(new Properties());
if (args.length > 1) {
emitter.setOutputStream(new FileOutputStream(args[1]));
} else {
emitter.setOutputStream(System.out);
}
NamespaceReducer r = new NamespaceReducer(emitter);
EventIteratorToReceiver.copy(puller, r);
System.err.println("Elapsed time: " + (System.currentTimeMillis() - startTime) + "ms");
}
}
/**
* Determine whether the EventIterator returns a flat sequence of events, or whether it can return
* nested event iterators
*
* @return true if the next() method is guaranteed never to return an EventIterator
*/
public boolean isFlatSequence() {
return false;
}
}
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