+ * This module, both source code and documentation, is in the + * Public Domain, and comes with NO WARRANTY. + * See http://www.saxproject.org + * for further information. + *+ * + *
This class wraps a SAX1 {@link org.xml.sax.Parser Parser} + * and makes it act as a SAX2 {@link org.xml.sax.XMLReader XMLReader}, + * with feature, property, and Namespace support. Note + * that it is not possible to report {@link org.xml.sax.ContentHandler#skippedEntity + * skippedEntity} events, since SAX1 does not make that information available.
+ * + *This adapter does not test for duplicate Namespace-qualified + * attribute names.
+ * + * @since SAX 2.0 + * @author David Megginson + * @version 2.0.1 (sax2r2) + * @see org.xml.sax.helpers.XMLReaderAdapter + * @see org.xml.sax.XMLReader + * @see org.xml.sax.Parser + */ +public class ParserAdapter implements XMLReader, DocumentHandler +{ + + + //////////////////////////////////////////////////////////////////// + // Constructors. + //////////////////////////////////////////////////////////////////// + + + /** + * Construct a new parser adapter. + * + *Use the "org.xml.sax.parser" property to locate the + * embedded SAX1 driver.
+ * + * @exception SAXException If the embedded driver + * cannot be instantiated or if the + * org.xml.sax.parser property is not specified. + */ + public ParserAdapter () + throws SAXException + { + super(); + + String driver = System.getProperty("org.xml.sax.parser"); + + try { + setup(ParserFactory.makeParser()); + } catch (ClassNotFoundException e1) { + throw new + SAXException("Cannot find SAX1 driver class " + + driver, e1); + } catch (IllegalAccessException e2) { + throw new + SAXException("SAX1 driver class " + + driver + + " found but cannot be loaded", e2); + } catch (InstantiationException e3) { + throw new + SAXException("SAX1 driver class " + + driver + + " loaded but cannot be instantiated", e3); + } catch (ClassCastException e4) { + throw new + SAXException("SAX1 driver class " + + driver + + " does not implement org.xml.sax.Parser"); + } catch (NullPointerException e5) { + throw new + SAXException("System property org.xml.sax.parser not specified"); + } + } + + + /** + * Construct a new parser adapter. + * + *Note that the embedded parser cannot be changed once the + * adapter is created; to embed a different parser, allocate + * a new ParserAdapter.
+ * + * @param parser The SAX1 parser to embed. + * @exception java.lang.NullPointerException If the parser parameter + * is null. + */ + public ParserAdapter (Parser parser) + { + super(); + setup(parser); + } + + + /** + * Internal setup method. + * + * @param parser The embedded parser. + * @exception java.lang.NullPointerException If the parser parameter + * is null. + */ + private void setup (Parser parser) + { + if (parser == null) { + throw new + NullPointerException("Parser argument must not be null"); + } + this.parser = parser; + atts = new AttributesImpl(); + nsSupport = new NamespaceSupport(); + attAdapter = new AttributeListAdapter(); + } + + + + //////////////////////////////////////////////////////////////////// + // Implementation of org.xml.sax.XMLReader. + //////////////////////////////////////////////////////////////////// + + + // + // Internal constants for the sake of convenience. + // + private final static String FEATURES = "http://xml.org/sax/features/"; + private final static String NAMESPACES = FEATURES + "namespaces"; + private final static String NAMESPACE_PREFIXES = FEATURES + "namespace-prefixes"; + private final static String XMLNS_URIs = FEATURES + "xmlns-uris"; + + + /** + * Set a feature flag for the parser. + * + *The only features recognized are namespaces and + * namespace-prefixes.
+ * + * @param name The feature name, as a complete URI. + * @param value The requested feature value. + * @exception SAXNotRecognizedException If the feature + * can't be assigned or retrieved. + * @exception SAXNotSupportedException If the feature + * can't be assigned that value. + * @see org.xml.sax.XMLReader#setFeature + */ + @Override + public void setFeature (String name, boolean value) + throws SAXNotRecognizedException, SAXNotSupportedException + { + if (name.equals(NAMESPACES)) { + checkNotParsing("feature", name); + namespaces = value; + if (!namespaces && !prefixes) { + prefixes = true; + } + } else if (name.equals(NAMESPACE_PREFIXES)) { + checkNotParsing("feature", name); + prefixes = value; + if (!prefixes && !namespaces) { + namespaces = true; + } + } else if (name.equals(XMLNS_URIs)) { + checkNotParsing("feature", name); + uris = value; + } else { + throw new SAXNotRecognizedException("Feature: " + name); + } + } + + + /** + * Check a parser feature flag. + * + *The only features recognized are namespaces and + * namespace-prefixes.
+ * + * @param name The feature name, as a complete URI. + * @return The current feature value. + * @exception SAXNotRecognizedException If the feature + * value can't be assigned or retrieved. + * @exception SAXNotSupportedException If the + * feature is not currently readable. + * @see org.xml.sax.XMLReader#setFeature + */ + @Override + public boolean getFeature (String name) + throws SAXNotRecognizedException, SAXNotSupportedException + { + if (name.equals(NAMESPACES)) { + return namespaces; + } else if (name.equals(NAMESPACE_PREFIXES)) { + return prefixes; + } else if (name.equals(XMLNS_URIs)) { + return uris; + } else { + throw new SAXNotRecognizedException("Feature: " + name); + } + } + + + /** + * Set a parser property. + * + *No properties are currently recognized.
+ * + * @param name The property name. + * @param value The property value. + * @exception SAXNotRecognizedException If the property + * value can't be assigned or retrieved. + * @exception SAXNotSupportedException If the property + * can't be assigned that value. + * @see org.xml.sax.XMLReader#setProperty + */ + @Override + public void setProperty (String name, Object value) + throws SAXNotRecognizedException, SAXNotSupportedException + { + throw new SAXNotRecognizedException("Property: " + name); + } + + + /** + * Get a parser property. + * + *No properties are currently recognized.
+ * + * @param name The property name. + * @return The property value. + * @exception SAXNotRecognizedException If the property + * value can't be assigned or retrieved. + * @exception SAXNotSupportedException If the property + * value is not currently readable. + * @see org.xml.sax.XMLReader#getProperty + */ + @Override + public Object getProperty (String name) + throws SAXNotRecognizedException, SAXNotSupportedException + { + throw new SAXNotRecognizedException("Property: " + name); + } + + + /** + * Set the entity resolver. + * + * @param resolver The new entity resolver. + * @see org.xml.sax.XMLReader#setEntityResolver + */ + @Override + public void setEntityResolver (EntityResolver resolver) + { + entityResolver = resolver; + } + + + /** + * Return the current entity resolver. + * + * @return The current entity resolver, or null if none was supplied. + * @see org.xml.sax.XMLReader#getEntityResolver + */ + @Override + public EntityResolver getEntityResolver () + { + return entityResolver; + } + + + /** + * Set the DTD handler. + * + * @param handler the new DTD handler + * @see org.xml.sax.XMLReader#setEntityResolver + */ + @Override + public void setDTDHandler (DTDHandler handler) + { + dtdHandler = handler; + } + + + /** + * Return the current DTD handler. + * + * @return the current DTD handler, or null if none was supplied + * @see org.xml.sax.XMLReader#getEntityResolver + */ + @Override + public DTDHandler getDTDHandler () + { + return dtdHandler; + } + + + /** + * Set the content handler. + * + * @param handler the new content handler + * @see org.xml.sax.XMLReader#setEntityResolver + */ + @Override + public void setContentHandler (ContentHandler handler) + { + contentHandler = handler; + } + + + /** + * Return the current content handler. + * + * @return The current content handler, or null if none was supplied. + * @see org.xml.sax.XMLReader#getEntityResolver + */ + @Override + public ContentHandler getContentHandler () + { + return contentHandler; + } + + + /** + * Set the error handler. + * + * @param handler The new error handler. + * @see org.xml.sax.XMLReader#setEntityResolver + */ + @Override + public void setErrorHandler (ErrorHandler handler) + { + errorHandler = handler; + } + + + /** + * Return the current error handler. + * + * @return The current error handler, or null if none was supplied. + * @see org.xml.sax.XMLReader#getEntityResolver + */ + @Override + public ErrorHandler getErrorHandler () + { + return errorHandler; + } + + + /** + * Parse an XML document. + * + * @param systemId The absolute URL of the document. + * @exception java.io.IOException If there is a problem reading + * the raw content of the document. + * @exception SAXException If there is a problem + * processing the document. + * @see #parse(org.xml.sax.InputSource) + * @see org.xml.sax.Parser#parse(java.lang.String) + */ + @Override + public void parse (String systemId) + throws IOException, SAXException + { + parse(new InputSource(systemId)); + } + + + /** + * Parse an XML document. + * + * @param input An input source for the document. + * @exception java.io.IOException If there is a problem reading + * the raw content of the document. + * @exception SAXException If there is a problem + * processing the document. + * @see #parse(java.lang.String) + * @see org.xml.sax.Parser#parse(org.xml.sax.InputSource) + */ + @Override + public void parse (InputSource input) + throws IOException, SAXException + { + if (parsing) { + throw new SAXException("Parser is already in use"); + } + setupParser(); + parsing = true; + try { + parser.parse(input); + } finally { + parsing = false; + } + parsing = false; + } + + + + //////////////////////////////////////////////////////////////////// + // Implementation of org.xml.sax.DocumentHandler. + //////////////////////////////////////////////////////////////////// + + + /** + * Adapter implementation method; do not call. + * Adapt a SAX1 document locator event. + * + * @param locator A document locator. + * @see org.xml.sax.ContentHandler#setDocumentLocator + */ + @Override + public void setDocumentLocator (Locator locator) + { + this.locator = locator; + if (contentHandler != null) { + contentHandler.setDocumentLocator(locator); + } + } + + + /** + * Adapter implementation method; do not call. + * Adapt a SAX1 start document event. + * + * @exception SAXException The client may raise a + * processing exception. + * @see org.xml.sax.DocumentHandler#startDocument + */ + @Override + public void startDocument () + throws SAXException + { + if (contentHandler != null) { + contentHandler.startDocument(); + } + } + + + /** + * Adapter implementation method; do not call. + * Adapt a SAX1 end document event. + * + * @exception SAXException The client may raise a + * processing exception. + * @see org.xml.sax.DocumentHandler#endDocument + */ + @Override + public void endDocument () + throws SAXException + { + if (contentHandler != null) { + contentHandler.endDocument(); + } + } + + + /** + * Adapter implementation method; do not call. + * Adapt a SAX1 startElement event. + * + *If necessary, perform Namespace processing.
+ * + * @param qName The qualified (prefixed) name. + * @param qAtts The XML attribute list (with qnames). + * @exception SAXException The client may raise a + * processing exception. + */ + @Override + public void startElement (String qName, AttributeList qAtts) + throws SAXException + { + // These are exceptions from the + // first pass; they should be + // ignored if there's a second pass, + // but reported otherwise. + Vector exceptions = null; + + // If we're not doing Namespace + // processing, dispatch this quickly. + if (!namespaces) { + if (contentHandler != null) { + attAdapter.setAttributeList(qAtts); + contentHandler.startElement("", "", qName.intern(), + attAdapter); + } + return; + } + + + // OK, we're doing Namespace processing. + nsSupport.pushContext(); + int length = qAtts.getLength(); + + // First pass: handle NS decls + for (int i = 0; i < length; i++) { + String attQName = qAtts.getName(i); + + if (!attQName.startsWith("xmlns")) + continue; + // Could be a declaration... + String prefix; + int n = attQName.indexOf(':'); + + // xmlns=... + if (n == -1 && attQName.length () == 5) { + prefix = ""; + } else if (n != 5) { + // XML namespaces spec doesn't discuss "xmlnsf:oo" + // (and similarly named) attributes ... at most, warn + continue; + } else // xmlns:foo=... + prefix = attQName.substring(n+1); + + String value = qAtts.getValue(i); + if (!nsSupport.declarePrefix(prefix, value)) { + reportError("Illegal Namespace prefix: " + prefix); + continue; + } + if (contentHandler != null) + contentHandler.startPrefixMapping(prefix, value); + } + + // Second pass: copy all relevant + // attributes into the SAX2 AttributeList + // using updated prefix bindings + atts.clear(); + for (int i = 0; i < length; i++) { + String attQName = qAtts.getName(i); + String type = qAtts.getType(i); + String value = qAtts.getValue(i); + + // Declaration? + if (attQName.startsWith("xmlns")) { + String prefix; + int n = attQName.indexOf(':'); + + if (n == -1 && attQName.length () == 5) { + prefix = ""; + } else if (n != 5) { + // XML namespaces spec doesn't discuss "xmlnsf:oo" + // (and similarly named) attributes ... ignore + prefix = null; + } else { + prefix = attQName.substring(6); + } + // Yes, decl: report or prune + if (prefix != null) { + if (prefixes) { + if (uris) + // note funky case: localname can be null + // when declaring the default prefix, and + // yet the uri isn't null. + atts.addAttribute (nsSupport.XMLNS, prefix, + attQName.intern(), type, value); + else + atts.addAttribute ("", "", + attQName.intern(), type, value); + } + continue; + } + } + + // Not a declaration -- report + try { + String attName[] = processName(attQName, true, true); + atts.addAttribute(attName[0], attName[1], attName[2], + type, value); + } catch (SAXException e) { + if (exceptions == null) + exceptions = new Vector(); + exceptions.addElement(e); + atts.addAttribute("", attQName, attQName, type, value); + } + } + + // now handle the deferred exception reports + if (exceptions != null && errorHandler != null) { + for (int i = 0; i < exceptions.size(); i++) + errorHandler.error((SAXParseException) + (exceptions.elementAt(i))); + } + + // OK, finally report the event. + if (contentHandler != null) { + String name[] = processName(qName, false, false); + contentHandler.startElement(name[0], name[1], name[2], atts); + } + } + + + /** + * Adapter implementation method; do not call. + * Adapt a SAX1 end element event. + * + * @param qName The qualified (prefixed) name. + * @exception SAXException The client may raise a + * processing exception. + * @see org.xml.sax.DocumentHandler#endElement + */ + @Override + public void endElement (String qName) + throws SAXException + { + // If we're not doing Namespace + // processing, dispatch this quickly. + if (!namespaces) { + if (contentHandler != null) { + contentHandler.endElement("", "", qName.intern()); + } + return; + } + + // Split the name. + String names[] = processName(qName, false, false); + if (contentHandler != null) { + contentHandler.endElement(names[0], names[1], names[2]); + Enumeration prefixes = nsSupport.getDeclaredPrefixes(); + while (prefixes.hasMoreElements()) { + String prefix = (String)prefixes.nextElement(); + contentHandler.endPrefixMapping(prefix); + } + } + nsSupport.popContext(); + } + + + /** + * Adapter implementation method; do not call. + * Adapt a SAX1 characters event. + * + * @param ch An array of characters. + * @param start The starting position in the array. + * @param length The number of characters to use. + * @exception SAXException The client may raise a + * processing exception. + * @see org.xml.sax.DocumentHandler#characters + */ + @Override + public void characters (char ch[], int start, int length) + throws SAXException + { + if (contentHandler != null) { + contentHandler.characters(ch, start, length); + } + } + + + /** + * Adapter implementation method; do not call. + * Adapt a SAX1 ignorable whitespace event. + * + * @param ch An array of characters. + * @param start The starting position in the array. + * @param length The number of characters to use. + * @exception SAXException The client may raise a + * processing exception. + * @see org.xml.sax.DocumentHandler#ignorableWhitespace + */ + @Override + public void ignorableWhitespace (char ch[], int start, int length) + throws SAXException + { + if (contentHandler != null) { + contentHandler.ignorableWhitespace(ch, start, length); + } + } + + + /** + * Adapter implementation method; do not call. + * Adapt a SAX1 processing instruction event. + * + * @param target The processing instruction target. + * @param data The remainder of the processing instruction + * @exception SAXException The client may raise a + * processing exception. + * @see org.xml.sax.DocumentHandler#processingInstruction + */ + @Override + public void processingInstruction (String target, String data) + throws SAXException + { + if (contentHandler != null) { + contentHandler.processingInstruction(target, data); + } + } + + + + //////////////////////////////////////////////////////////////////// + // Internal utility methods. + //////////////////////////////////////////////////////////////////// + + + /** + * Initialize the parser before each run. + */ + private void setupParser () + { + // catch an illegal "nonsense" state. + if (!prefixes && !namespaces) + throw new IllegalStateException (); + + nsSupport.reset(); + if (uris) + nsSupport.setNamespaceDeclUris (true); + + if (entityResolver != null) { + parser.setEntityResolver(entityResolver); + } + if (dtdHandler != null) { + parser.setDTDHandler(dtdHandler); + } + if (errorHandler != null) { + parser.setErrorHandler(errorHandler); + } + parser.setDocumentHandler(this); + locator = null; + } + + + /** + * Process a qualified (prefixed) name. + * + *If the name has an undeclared prefix, use only the qname + * and make an ErrorHandler.error callback in case the app is + * interested.
+ * + * @param qName The qualified (prefixed) name. + * @param isAttribute true if this is an attribute name. + * @return The name split into three parts. + * @exception SAXException The client may throw + * an exception if there is an error callback. + */ + private String [] processName (String qName, boolean isAttribute, + boolean useException) + throws SAXException + { + String parts[] = nsSupport.processName(qName, nameParts, + isAttribute); + if (parts == null) { + if (useException) + throw makeException("Undeclared prefix: " + qName); + reportError("Undeclared prefix: " + qName); + parts = new String[3]; + parts[0] = parts[1] = ""; + parts[2] = qName.intern(); + } + return parts; + } + + + /** + * Report a non-fatal error. + * + * @param message The error message. + * @exception SAXException The client may throw + * an exception. + */ + void reportError (String message) + throws SAXException + { + if (errorHandler != null) + errorHandler.error(makeException(message)); + } + + + /** + * Construct an exception for the current context. + * + * @param message The error message. + */ + private SAXParseException makeException (String message) + { + if (locator != null) { + return new SAXParseException(message, locator); + } else { + return new SAXParseException(message, null, null, -1, -1); + } + } + + + /** + * Throw an exception if we are parsing. + * + *Use this method to detect illegal feature or + * property changes.
+ * + * @param type The type of thing (feature or property). + * @param name The feature or property name. + * @exception SAXNotSupportedException If a + * document is currently being parsed. + */ + private void checkNotParsing (String type, String name) + throws SAXNotSupportedException + { + if (parsing) { + throw new SAXNotSupportedException("Cannot change " + + type + ' ' + + name + " while parsing"); + + } + } + + + + //////////////////////////////////////////////////////////////////// + // Internal state. + //////////////////////////////////////////////////////////////////// + + private NamespaceSupport nsSupport; + private AttributeListAdapter attAdapter; + + private boolean parsing = false; + private String nameParts[] = new String[3]; + + private Parser parser = null; + + private AttributesImpl atts = null; + + // Features + private boolean namespaces = true; + private boolean prefixes = false; + private boolean uris = false; + + // Properties + + // Handlers + Locator locator; + + EntityResolver entityResolver = null; + DTDHandler dtdHandler = null; + ContentHandler contentHandler = null; + ErrorHandler errorHandler = null; + + + + //////////////////////////////////////////////////////////////////// + // Inner class to wrap an AttributeList when not doing NS proc. + //////////////////////////////////////////////////////////////////// + + + /** + * Adapt a SAX1 AttributeList as a SAX2 Attributes object. + * + *This class is in the Public Domain, and comes with NO + * WARRANTY of any kind.
+ * + *This wrapper class is used only when Namespace support + * is disabled -- it provides pretty much a direct mapping + * from SAX1 to SAX2, except that names and types are + * interned whenever requested.
+ */ + final class AttributeListAdapter implements Attributes + { + + /** + * Construct a new adapter. + */ + AttributeListAdapter () + { + } + + + /** + * Set the embedded AttributeList. + * + *This method must be invoked before any of the others + * can be used.
+ * + * @param The SAX1 attribute list (with qnames). + */ + void setAttributeList (AttributeList qAtts) + { + this.qAtts = qAtts; + } + + + /** + * Return the length of the attribute list. + * + * @return The number of attributes in the list. + * @see org.xml.sax.Attributes#getLength + */ + @Override + public int getLength () + { + return qAtts.getLength(); + } + + + /** + * Return the Namespace URI of the specified attribute. + * + * @param The attribute's index. + * @return Always the empty string. + * @see org.xml.sax.Attributes#getURI + */ + @Override + public String getURI (int i) + { + return ""; + } + + + /** + * Return the local name of the specified attribute. + * + * @param The attribute's index. + * @return Always the empty string. + * @see org.xml.sax.Attributes#getLocalName + */ + @Override + public String getLocalName (int i) + { + return ""; + } + + + /** + * Return the qualified (prefixed) name of the specified attribute. + * + * @param The attribute's index. + * @return The attribute's qualified name, internalized. + */ + @Override + public String getQName (int i) + { + return qAtts.getName(i).intern(); + } + + + /** + * Return the type of the specified attribute. + * + * @param The attribute's index. + * @return The attribute's type as an internalized string. + */ + @Override + public String getType (int i) + { + return qAtts.getType(i).intern(); + } + + + /** + * Return the value of the specified attribute. + * + * @param The attribute's index. + * @return The attribute's value. + */ + @Override + public String getValue (int i) + { + return qAtts.getValue(i); + } + + + /** + * Look up an attribute index by Namespace name. + * + * @param uri The Namespace URI or the empty string. + * @param localName The local name. + * @return The attributes index, or -1 if none was found. + * @see org.xml.sax.Attributes#getIndex(java.lang.String,java.lang.String) + */ + @Override + public int getIndex (String uri, String localName) + { + return -1; + } + + + /** + * Look up an attribute index by qualified (prefixed) name. + * + * @param qName The qualified name. + * @return The attributes index, or -1 if none was found. + * @see org.xml.sax.Attributes#getIndex(java.lang.String) + */ + @Override + public int getIndex (String qName) + { + int max = atts.getLength(); + for (int i = 0; i < max; i++) { + if (qAtts.getName(i).equals(qName)) { + return i; + } + } + return -1; + } + + + /** + * Look up the type of an attribute by Namespace name. + * + * @param uri The Namespace URI + * @param localName The local name. + * @return The attribute's type as an internalized string. + */ + @Override + public String getType (String uri, String localName) + { + return null; + } + + + /** + * Look up the type of an attribute by qualified (prefixed) name. + * + * @param qName The qualified name. + * @return The attribute's type as an internalized string. + */ + @Override + public String getType (String qName) + { + return qAtts.getType(qName).intern(); + } + + + /** + * Look up the value of an attribute by Namespace name. + * + * @param uri The Namespace URI + * @param localName The local name. + * @return The attribute's value. + */ + @Override + public String getValue (String uri, String localName) + { + return null; + } + + + /** + * Look up the value of an attribute by qualified (prefixed) name. + * + * @param qName The qualified name. + * @return The attribute's value. + */ + @Override + public String getValue (String qName) + { + return qAtts.getValue(qName); + } + + private AttributeList qAtts; + } +} + +// end of ParserAdapter.java