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A library jar that provides APIs for Applications written for the Google Android Platform.

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// ParserAdapter.java - adapt a SAX1 Parser to a SAX2 XMLReader.
// http://www.saxproject.org
// Written by David Megginson
// NO WARRANTY!  This class is in the public domain.
// $Id: ParserAdapter.java,v 1.16 2004/04/26 17:34:35 dmegginson Exp $

package org.xml.sax.helpers;

import java.io.IOException;
import java.util.ArrayList;
import java.util.Enumeration;
import org.xml.sax.AttributeList;
import org.xml.sax.Attributes;
import org.xml.sax.ContentHandler;
import org.xml.sax.DTDHandler;
import org.xml.sax.DocumentHandler;
import org.xml.sax.EntityResolver;
import org.xml.sax.ErrorHandler;
import org.xml.sax.InputSource;
import org.xml.sax.Locator;
import org.xml.sax.Parser;
import org.xml.sax.SAXException;
import org.xml.sax.SAXNotRecognizedException;
import org.xml.sax.SAXNotSupportedException;
import org.xml.sax.SAXParseException;
import org.xml.sax.XMLReader;


/**
 * Adapt a SAX1 Parser as a SAX2 XMLReader.
 *
 * 
* 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 { 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) { 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 static final String FEATURES = "http://xml.org/sax/features/"; private static final String NAMESPACES = FEATURES + "namespaces"; private static final String NAMESPACE_PREFIXES = FEATURES + "namespace-prefixes"; private static final 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 */ 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 */ 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 */ 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 */ 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 */ 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 */ public EntityResolver getEntityResolver () { return entityResolver; } /** * Set the DTD handler. * * @param handler the new DTD handler * @see org.xml.sax.XMLReader#setEntityResolver */ 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 */ public DTDHandler getDTDHandler () { return dtdHandler; } /** * Set the content handler. * * @param handler the new content handler * @see org.xml.sax.XMLReader#setEntityResolver */ 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 */ public ContentHandler getContentHandler () { return contentHandler; } /** * Set the error handler. * * @param handler The new error handler. * @see org.xml.sax.XMLReader#setEntityResolver */ 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 */ 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) */ 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) */ 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 */ 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 */ 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 */ 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. */ 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. ArrayList 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 ArrayList(); } exceptions.add((SAXParseException) e); atts.addAttribute("", attQName, attQName, type, value); } } // now handle the deferred exception reports if (exceptions != null && errorHandler != null) { for (SAXParseException ex : exceptions) { errorHandler.error(ex); } } // 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 */ 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 */ 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 */ 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 */ 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 */ 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 */ 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 */ 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. */ 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. */ 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. */ 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) */ 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) */ 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. */ 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. */ 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. */ 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. */ public String getValue (String qName) { return qAtts.getValue(qName); } private AttributeList qAtts; } } // end of ParserAdapter.java




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