saxhandler.java

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	public void startEntity(String name) throws SAXException {
		if (D.ON && log.finerable()) log.finer("startEntity: " + name);

		//A "[dtd]" entity indicates the beginning of the external subset
		if (name.equals("[dtd]")) {
			_inInternSubset = false;
			return;
		}

		if (!isExpandEntityReferences() && !_inDTD && !entityToSkip(name)) {
			pushGroup(_factory.newEntityRef(name));
		}
	}
	/** Tests whether the name is something that always expanded. */
	private boolean entityToSkip(String name) {
		//To speed up the performance, we don't compare all strings
		//Rather, we use something similar to finite-state machine.
		switch (name.charAt(0)) {
		case 'a': return name.equals("amp") || name.equals("apos");
		case 'g': return name.equals("gt");
		case 'l': return name.equals("lt");
		case 'q': return name.equals("quot");
		}
		return false;
	}

	public void endEntity(String name) throws SAXException {
		if (D.ON && log.finerable()) log.finer("endEntity: " + name);

		if (name.equals("[dtd]")) {
			_inInternSubset = false;
			return;
		}
		if (!isExpandEntityReferences() && !_inDTD && !entityToSkip(name)) {
			popGroup();
		}
	}

	public void startCDATA() throws SAXException {
		_inCData = true;
	}

	public void endCDATA() throws SAXException {
		_inCData = false;
	}

	public void comment(char[] ch, int start, int length) throws SAXException {
		if (length == 0 || isIgnoringComments())
			return; //ignore zero length

		String data = new String(ch, start, length);
		if (_inDTD && _inInternSubset && !isExpandEntityReferences()) {
			_internSubset.append("  <!--").append(data).append("-->\n");
		}
		if (!_inDTD && data.length() != 0) {
			addToCurrentGroup(_factory.newComment(data));
		}
	}

	//-- org.xml.sax.ContentHandler --//
	public void startDocument() throws SAXException {
		_declNamespaces = new LinkedList();
		_stack =  new Stack();

		_doc = _factory.newDocument(null, null);
		pushGroup(_doc);
	}
	public void endDocument() throws SAXException {
		popGroup();
		assert(_stack.isEmpty());

		_stack = null;
		_loc = null;
		_declNamespaces = null;
	}

	public void setDocumentLocator(Locator locator) {
		_loc = locator;
	}

	public void processingInstruction(String target, String data)
	throws SAXException {
		addToCurrentGroup(_factory.newProcessingInstruction(target, data));
	}

	public void startPrefixMapping(String prefix, String uri)
	throws SAXException {
		if (D.ON && log.finerable())
			log.finer("start prefix: " + prefix + ", " + uri + SimpleLocator.toString(_loc));

		final Namespace ns = Namespace.getSpecial(prefix);
		if (ns == null || !ns.getURI().equals(uri))
			_declNamespaces.add(0, new Namespace(prefix, uri));
			//TY: add at the head to speed up the searching
	}

	public void endPrefixMapping(String prefix) throws SAXException {
		if (D.ON && log.finerable())
			log.finer("end prefix: " + prefix + SimpleLocator.toString(_loc));

		for (Iterator itr = _declNamespaces.iterator(); itr.hasNext();) {
			final Namespace ns = (Namespace) itr.next();
			if (prefix.equals(ns.getPrefix())) {
				itr.remove();
				break;
			}
		}
	}

	public void
	startElement(String nsURI, String lname, String tname, Attributes attrs)
	throws SAXException {
		if (D.ON && log.finerable())
			log.finer("start element: nsURI=\"" + nsURI + "\", lname=" + lname + ", tname=" + tname
				+ " attr#=" + attrs.getLength() + SimpleLocator.toString(_loc));

		//create the element
		if (tname == null || tname.length() == 0) //just in case
			tname = lname;
		final Element element = newElement(nsURI, tname);
			//note: in crimson, lname might be empty, so...

		//Handle attributes
		for (int j=0, len=attrs.getLength(); j<len; j++) {
			String attQname = attrs.getQName(j);
			String attLname = attrs.getLocalName(j);

			if (attQname == null || attQname.length() == 0) //just in case
				attQname = attLname;

			final Attribute attr;
			int kp = attQname.indexOf(':');
			if (kp >= 0) {
				final String prefix = attQname.substring(0, kp);
				final Namespace ns = element.getNamespace(prefix);
				if (ns == null)
					throw new SAXException("Unknown prefix: "+prefix+" at "+_loc+"\nDo you forget to turn on namespace-aware");
				attr = _factory.newAttribute(
					ns, attQname.substring(kp + 1), attrs.getValue(j));
					//if prefix, attLname might be empty so use attQname
			} else {
				attr = _factory.newAttribute(
					attLname == null || attLname.length() == 0 ?
						attQname: attLname, //crimson might use empty for AttLname
					attrs.getValue(j));
			}
			attachLocator(attr);
			element.getAttributeItems().add(attr);
			//Don't use setAttribute, to can detect replicated attributes
		}
	}
	private Element newElement(String nsURI, String tname)
	throws SAXException {
		if (nsURI == null) nsURI = "";

		final int j = tname.indexOf(':');
		final String prefix = j >= 0 ? tname.substring(0, j): "";
		final String lname = j >= 0 ? tname.substring(j + 1): tname;

		Namespace ns;
		final Group parent = getTopGroup();
		if (parent instanceof Element) {
			ns = ((Element)parent).getNamespace(prefix);
			if (ns != null && !ns.getURI().equals(nsURI)) //override
				ns = null; //create a no-namespace element first
		} else {
			ns = Namespace.getSpecial(prefix);
		}

		if (ns == null) {
			if (_declNamespaces.size() > 0) {
				for (Iterator it = _declNamespaces.iterator(); it.hasNext();) {
					final Namespace n = (Namespace)it.next();
					if (n.getPrefix().equals(prefix) && n.getURI().equals(nsURI)) {
						if (D.ON && log.finerable()) log.finer("Namespace found in _declNamespaces: "+n);
						ns = n;
						break; //found
					}
				}
			}
			if (ns == null && nsURI.length() > 0) {
				if (D.ON && log.finerable()) log.finer("Create namespace: "+prefix+" "+nsURI);
				ns = new Namespace(prefix, nsURI);
			}
		}

		final Element element = ns != null ?
			_factory.newElement(ns, lname): _factory.newElement(lname);

		//add to element's add. namespaces
		if (_declNamespaces.size() > 0) {
			for (Iterator it = _declNamespaces.iterator(); it.hasNext();)
				element.addDeclaredNamespace((Namespace)it.next());
			_declNamespaces.clear();
		}

		pushGroup(element);
		return element;
	}
	public void endElement
	(String nsURI, String lname, String tname) throws SAXException {
		if (D.ON && log.finerable())
			log.finer("end element: " + nsURI + ", " + lname + ", " + tname);

		popGroup();
	}

	public void characters(char[] ch, int start, int length)
	throws SAXException {
		if (length == 0) return; //ignore zero length

		//Note: Element's add will coalesce consecutive CDATA or Text
		final String data = new String(ch, start, length);
		if (getTopGroup() instanceof Document) {
			if (data.trim().length() > 0)
				throw new SAXException("Adding non-empty text to Document: "+data);
			return; //Under transforming, it is possible to have this case
		}

		if (_inCData && !isCoalescing())
			addToCurrentGroup(_factory.newCData(data));
		else
			addToCurrentGroup(_factory.newText(data));
	}

	public void ignorableWhitespace(char[] ch, int start, int length)
	throws SAXException {
		if (length == 0 || isIgnoringElementContentWhitespace())
			return;

		addToCurrentGroup(_factory.newText(new String(ch, start, length)));
	}

	//-- org.xml.sax.DTDHandler --//
	public void notationDecl(String name, String publicID, String systemID)
	throws SAXException {
		if (!_inInternSubset)
			return;

		_internSubset.append("  <!NOTATION ").append(name)
			.append(" \"").append(systemID).append("\">\n");
	}

	public void unparsedEntityDecl
	(String name, String pubId, String sysId, String notationName)
	throws SAXException {
		if (D.ON && log.finerable())
			log.finer("externalEntityDecl: " + name + " p:" + pubId + " s:" + sysId + " n:" + notationName);

		if (!_inInternSubset)
			return;

		_internSubset.append("  <!ENTITY ").append(name);

		if (pubId != null)
			_internSubset.append(" PUBLIC \"").append(pubId).append("\" ");
		if (sysId != null)
			_internSubset.append(" SYSTEM \"").append(sysId).append("\" ");

		_internSubset.append(" NDATA ").append(notationName).append(">\n");
	}

	//-- org.xml.sax.EntityResolver --//
	public InputSource resolveEntity(String publicId, String systemId)
	throws SAXException {
		if (D.ON && log.finerable())
			log.finer("resolveEntity public="+publicId+" system="+systemId);

		EntityResolver er = getEntityResolver();
		if (er != null) {
			try {
				return er.resolveEntity(publicId, systemId);
			} catch (IOException ex) {
				//unfortunately, DefaultHandler doesn't throw IOException,
				//so we have to wrap it
				throw new SAXException(ex);
			}
		} else {
			InputSource is = defaultResolveEntity(publicId, systemId);
			if (D.ON && is == null && log.finerable())
				log.finer("Unable to resolve public="+publicId+" system="+systemId);
			return is;
		}
	}
	/** The default entity resolver.
	 * It is used if {@link #setEntityResolver} is not called.
	 * This implementation searches the class path under /metainfo/xml.
	 *
	 * <p>For example, http://java.sun.com/xml/ns/portlet/portlet-app_1_0.xsd
	 * is asked.
	 * It searches from classpath
	 * for /metainfo/xml/java.sun.com/xml/ns/portlet/portlet-app_1_0.xsd
	 * and /metainfo/xml/portlet-app_1_0.xsd
	 */
	protected InputSource defaultResolveEntity(String publicId, String systemId)
	throws SAXException {
		if (systemId == null)
			return null;

		//Try the original form first if "file:/" found (including jar:file:/)
		//We don't need to handle others, because http:// will be resolved
		//by parser. And, if we do it here, we lost the chance to improve
		//performance by loading it locally by below codes
		if (systemId.indexOf("file:/") >= 0) {
			try {
				final InputSource is = new InputSource(new URL(systemId).openStream());
				is.setSystemId(systemId);
				if (D.ON && log.finerable()) log.finer("Entity found "+systemId);
				return is;
			} catch (Exception ex) {
				if (D.ON && log.finerable()) log.finer("Unable to open "+systemId);
			}
		}

		final String PREFIX = "/metainfo/xml";
		final org.zkoss.util.resource.Locator loader = Locators.getDefault();

		URL url = null;
		int j = systemId.indexOf("://");
		if (j > 0) {
			final String resId = PREFIX + systemId.substring(j + 2);
			url = loader.getResource(resId);
		}
		if (url == null) {
			j = systemId.lastIndexOf('/');
			final String resId = j >= 0 ? PREFIX + systemId.substring(j): PREFIX + '/' + systemId;
			url = loader.getResource(resId);
		}
		if (url != null) {
			if (D.ON && log.finerable()) log.finer("Entity resovled to "+url);
			try {
			    final InputSource is = new InputSource(url.openStream());
			    is.setSystemId(url.toExternalForm());
			    return is;
			} catch (IOException ex) {
				throw new SAXException(ex); //not possible because Locator is used
			}
		}
		return null;
	}

	//-- org.xml.sax.ErrorHandler --//
	public void warning(SAXParseException ex) throws SAXException {
		ErrorHandler eh = getErrorHandler();
		if (eh != null) {
			eh.warning(ex);
		} else {
			log.warning(ex.getMessage() + SimpleLocator.toString(_loc));
		}
	}
	public void error(SAXParseException ex) throws SAXException {
		ErrorHandler eh = getErrorHandler();
		if (eh != null) {
			eh.error(ex);
		} else {
			log.error(ex.getMessage() + SimpleLocator.toString(_loc));
			throw ex;
		}
	}
	public void fatalError(SAXParseException ex) throws SAXException {
		ErrorHandler eh = getErrorHandler();
		if (eh != null) {
			eh.fatalError(ex);
		} else {
			log.error(ex.getMessage() + SimpleLocator.toString(_loc));
			throw ex;
		}
	}
}