xmlparser.java

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	expandPE = false;
	parseUntil ("--");
	require ('>');
	expandPE = saved;
	handler.comment (dataBuffer, 0, dataBufferPos);
	dataBufferPos = 0;
    }


    /**
     * Parse a processing instruction and do a call-back.
     * <pre>
     * [16] PI ::= '&lt;?' PITarget
     *		(S (Char* - (Char* '?&gt;' Char*)))?
     *		'?&gt;'
     * [17] PITarget ::= Name - ( ('X'|'x') ('M'|m') ('L'|l') )
     * </pre>
     * <p> (The <code>&lt;?</code> has already been read.)
     */
    private void parsePI ()
    throws SAXException, IOException
    {
	String name;
	boolean saved = expandPE;

	expandPE = false;
	name = readNmtoken (true);
	if ("xml".equalsIgnoreCase (name))
	    error ("Illegal processing instruction target", name, null);
	if (!tryRead ("?>")) {
	    requireWhitespace ();
	    parseUntil ("?>");
	}
	expandPE = saved;
	handler.processingInstruction (name, dataBufferToString ());
    }


    /**
     * Parse a CDATA section.
     * <pre>
     * [18] CDSect ::= CDStart CData CDEnd
     * [19] CDStart ::= '&lt;![CDATA['
     * [20] CData ::= (Char* - (Char* ']]&gt;' Char*))
     * [21] CDEnd ::= ']]&gt;'
     * </pre>
     * <p> (The '&lt;![CDATA[' has already been read.)
     */
    private void parseCDSect ()
    throws Exception
    {
	parseUntil ("]]>");
	dataBufferFlush ();
    }


    /**
     * Parse the prolog of an XML document.
     * <pre>
     * [22] prolog ::= XMLDecl? Misc* (Doctypedecl Misc*)?
     * </pre>
     * <p>There are a couple of tricks here.  First, it is necessary to
     * declare the XML default attributes after the DTD (if present)
     * has been read. [??]  Second, it is not possible to expand general
     * references in attribute value literals until after the entire
     * DTD (if present) has been parsed.
     * <p>We do not look for the XML declaration here, because it was
     * handled by pushURL ().
     * @see pushURL
     */
    private void parseProlog ()
    throws Exception
    {
	parseMisc ();

	if (tryRead ("<!DOCTYPE")) {
	    parseDoctypedecl ();
	    parseMisc ();
	}
    }


    /**
     * Parse the XML declaration.
     * <pre>
     * [23] XMLDecl ::= '&lt;?xml' VersionInfo EncodingDecl? SDDecl? S? '?&gt;'
     * [24] VersionInfo ::= S 'version' Eq
     *		("'" VersionNum "'" | '"' VersionNum '"' )
     * [26] VersionNum ::= ([a-zA-Z0-9_.:] | '-')*
     * [32] SDDecl ::= S 'standalone' Eq
     *		( "'"" ('yes' | 'no') "'"" | '"' ("yes" | "no") '"' )
     * [80] EncodingDecl ::= S 'encoding' Eq
     *		( "'" EncName "'" | "'" EncName "'" )
     * [81] EncName ::= [A-Za-z] ([A-Za-z0-9._] | '-')*
     * </pre>
     * <p> (The <code>&lt;?xml</code> and whitespace have already been read.)
     * @return the encoding in the declaration, uppercased; or null
     * @see #parseTextDecl
     * @see #setupDecoding
     */
    private String parseXMLDecl (boolean ignoreEncoding)
    throws SAXException, IOException
    {
	String	version;
	String	encodingName = null;
	String	standalone = null;
	boolean	white;
	int	flags = LIT_DISABLE_CREF | LIT_DISABLE_PE | LIT_DISABLE_EREF;

	// Read the version.
	require ("version");
	parseEq ();
	version = readLiteral (flags);
	if (!version.equals ("1.0")) {
	    error ("unsupported XML version", version, "1.0");
	}

	// Try reading an encoding declaration.
	white = tryWhitespace ();
	if (tryRead ("encoding")) {
	    if (!white)
		error ("whitespace required before 'encoding='");
	    parseEq ();
	    encodingName = readLiteral (flags);
	    if (!ignoreEncoding)
		setupDecoding (encodingName);
	}

	// Try reading a standalone declaration
	if (encodingName != null)
	    white = tryWhitespace ();
	if (tryRead ("standalone")) {
	    if (!white)
		error ("whitespace required before 'standalone='");
	    parseEq ();
	    standalone = readLiteral (flags);
	    if (! ("yes".equals (standalone) || "no".equals (standalone)))
		error ("standalone flag must be 'yes' or 'no'");
	}

	skipWhitespace ();
	require ("?>");

	return encodingName;
    }


    /**
     * Parse a text declaration.
     * <pre>
     * [79] TextDecl ::= '&lt;?xml' VersionInfo? EncodingDecl S? '?&gt;'
     * [80] EncodingDecl ::= S 'encoding' Eq
     *		( '"' EncName '"' | "'" EncName "'" )
     * [81] EncName ::= [A-Za-z] ([A-Za-z0-9._] | '-')*
     * </pre>
     * <p> (The <code>&lt;?xml</code>' and whitespace have already been read.)
     * @return the encoding in the declaration, uppercased; or null
     * @see #parseXMLDecl
     * @see #setupDecoding
     */
    private String parseTextDecl (boolean ignoreEncoding)
    throws SAXException, IOException
    {
	String	encodingName = null;
	int	flags = LIT_DISABLE_CREF | LIT_DISABLE_PE | LIT_DISABLE_EREF;

	// Read an optional version.
	if (tryRead ("version")) {
	    String version;
	    parseEq ();
	    version = readLiteral (flags);
	    if (!version.equals ("1.0")) {
		error ("unsupported XML version", version, "1.0");
	    }
	    requireWhitespace ();
	}


	// Read the encoding.
	require ("encoding");
	parseEq ();
	encodingName = readLiteral (flags);
	if (!ignoreEncoding)
	    setupDecoding (encodingName);

	skipWhitespace ();
	require ("?>");

	return encodingName;
    }


    /**
     * Sets up internal state so that we can decode an entity using the
     * specified encoding.  This is used when we start to read an entity
     * and we have been given knowledge of its encoding before we start to
     * read any data (e.g. from a SAX input source or from a MIME type).
     *
     * <p> It is also used after autodetection, at which point only very
     * limited adjustments to the encoding may be used (switching between
     * related builtin decoders).
     *
     * @param encodingName The name of the encoding specified by the user.
     * @exception IOException if the encoding isn't supported either
     *	internally to this parser, or by the hosting JVM.
     * @see #parseXMLDecl
     * @see #parseTextDecl
     */
    private void setupDecoding (String encodingName)
    throws SAXException, IOException
    {
	encodingName = encodingName.toUpperCase ();

	// ENCODING_EXTERNAL indicates an encoding that wasn't
	// autodetected ... we can use builtin decoders, or
	// ones from the JVM (InputStreamReader).

	// Otherwise we can only tweak what was autodetected, and
	// only for single byte (ASCII derived) builtin encodings.

	// ASCII-derived encodings
	if (encoding == ENCODING_UTF_8 || encoding == ENCODING_EXTERNAL) {
	    if (encodingName.equals ("ISO-8859-1")
		    || encodingName.equals ("8859_1")
		    || encodingName.equals ("ISO8859_1")
	      ) {
		encoding = ENCODING_ISO_8859_1;
		return;
	    } else if (encodingName.equals ("US-ASCII")
			|| encodingName.equals ("ASCII")) {
		encoding = ENCODING_ASCII;
		return;
	    } else if (encodingName.equals ("UTF-8")
			|| encodingName.equals ("UTF8")) {
		encoding = ENCODING_UTF_8;
		return;
	    } else if (encoding != ENCODING_EXTERNAL) {
		// fatal error
		error ("unsupported ASCII-derived encoding",
		       encodingName,
		       "UTF-8, US-ASCII, or ISO-8859-1");
	    }
	    // else fallthrough ...
	    // it's ASCII-ish and something other than a builtin
	}

	// Unicode and such
	if (encoding == ENCODING_UCS_2_12 || encoding == ENCODING_UCS_2_21) {
	    if (!(encodingName.equals ("ISO-10646-UCS-2")
		    || encodingName.equals ("UTF-16")
		    || encodingName.equals ("UTF-16BE")
		    || encodingName.equals ("UTF-16LE")))
		error ("unsupported Unicode encoding",
		       encodingName,
		       "UTF-16");
	    return;
	}

	// four byte encodings
	if (encoding == ENCODING_UCS_4_1234
		|| encoding == ENCODING_UCS_4_4321
		|| encoding == ENCODING_UCS_4_2143
		|| encoding == ENCODING_UCS_4_3412) {
	    if (!encodingName.equals ("ISO-10646-UCS-4"))
		error ("unsupported 32-bit encoding",
		       encodingName,
		       "ISO-10646-UCS-4");
	    return;
	}

	// assert encoding == ENCODING_EXTERNAL
	// if (encoding != ENCODING_EXTERNAL)
	//     throw new RuntimeException ("encoding = " + encoding);

	if (encodingName.equals ("UTF-16BE")) {
	    encoding = ENCODING_UCS_2_12;
	    return;
	}
	if (encodingName.equals ("UTF-16LE")) {
	    encoding = ENCODING_UCS_2_21;
	    return;
	}

	// We couldn't use the builtin decoders at all.  But we can try to
	// create a reader, since we haven't messed up buffering.  Tweak
	// the encoding name if necessary.

	if (encodingName.equals ("UTF-16")
		|| encodingName.equals ("ISO-10646-UCS-2"))
	    encodingName = "Unicode";
	// Ignoring all the EBCDIC aliases here

	reader = new InputStreamReader (is, encodingName);
	sourceType = INPUT_READER;
	is = null;
    }


    /**
     * Parse miscellaneous markup outside the document element and DOCTYPE
     * declaration.
     * <pre>
     * [27] Misc ::= Comment | PI | S
     * </pre>
     */
    private void parseMisc ()
    throws Exception
    {
	while (true) {
	    skipWhitespace ();
	    if (tryRead ("<?")) {
		parsePI ();
	    } else if (tryRead ("<!--")) {
		parseComment ();
	    } else {
		return;
	    }
	}
    }


    /**
     * Parse a document type declaration.
     * <pre>
     * [28] doctypedecl ::= '&lt;!DOCTYPE' S Name (S ExternalID)? S?
     *		('[' (markupdecl | PEReference | S)* ']' S?)? '&gt;'
     * </pre>
     * <p> (The <code>&lt;!DOCTYPE</code> has already been read.)
     */
    private void parseDoctypedecl ()
    throws Exception
    {
	char c;
	String doctypeName, ids[];

	// Read the document type name.
	requireWhitespace ();
	doctypeName = readNmtoken (true);

	// Read the External subset's IDs
	skipWhitespace ();
	ids = readExternalIds (false);

	// report (a) declaration of name, (b) lexical info (ids)
	handler.doctypeDecl (doctypeName, ids [0], ids [1]);

	// Internal subset is parsed first, if present
	skipWhitespace ();
	if (tryRead ('[')) {

	    // loop until the subset ends
	    while (true) {
		expandPE = true;
		skipWhitespace ();
		expandPE = false;
		if (tryRead (']')) {
		    break; 		// end of subset
		} else {
		    // WFC, PEs in internal subset (only between decls)
		    peIsError = expandPE = true;
		    parseMarkupdecl ();
		    peIsError = expandPE = false;
		}
	    }
	}

	// Read the external subset, if any
	if (ids [1] != null) {
	    pushURL ("[external subset]", ids [0], ids [1], null, null, null);

	    // Loop until we end up back at '>'
	    while (true) {
		expandPE = true;
		skipWhitespace ();
		expandPE = false;
		if (tryRead ('>')) {
		    break;
		} else {
		    expandPE = true;
		    parseMarkupdecl ();
		    expandPE = false;
		}
	    }
	} else {
	    // No external subset.
	    skipWhitespace ();
	    require ('>');
	}

	// done dtd
	handler.endDoctype ();
	expandPE = false;
    }


    /**
     * Parse a markup declaration in the internal or external DTD subset.
     * <pre>
     * [29] markupdecl ::= elementdecl | Attlistdecl | EntityDecl
     *		| NotationDecl | PI | Comment
     * [30] extSubsetDecl ::= (markupdecl | conditionalSect
     *		| PEReference | S) *
     * </pre>
     * <p> Reading toplevel PE references is handled as a lexical issue
     * by the caller, as is whitespace.
     */
    private void parseMarkupdecl ()
    throws Exception
    {
	if (tryRead ("<!ELEMENT")) {
	    parseElementdecl ();
	} else if (tryRead ("<!ATTLIST")) {
	    parseAttlistDecl ();
	} else if (tryRead ("<!ENTITY")) {
	    parseEntityDecl ();
	} else if (tryRead ("<!NOTATION")) {
	    parseNotationDecl ();
	} else if (tryRead ("<?")) {
	    parsePI ();
	} else if (tryRead ("<!--")) {
	    parseComment ();
	} else if (tryRead ("<![")) {
	    if (inputStack.size () > 0)
		parseConditionalSect ();
	    else
		error ("conditional sections illegal in internal subset");
	} else {
	    error ("expected markup declaration");
	}
    }


    /**
     * Parse an element, with its tags.
     * <pre>
     * [39] element ::= EmptyElementTag | STag content ETag
     * [40] STag ::= '&lt;' Name (S Attribute)* S? '&gt;'
     * [44] EmptyElementTag ::= '&lt;' Name (S Attribute)* S? '/&gt;'
     * </pre>
     * <p> (The '&lt;' has already been read.)
     * <p>NOTE: this method actually chains onto parseContent (), if necessary,
     * and parseContent () will take care of calling parseETag ().
     */
    private void parseElement ()
    throws Exception
    {
	String	gi;
	char	c;
	int	oldElementContent = currentElementContent;
	String	oldElement = currentElement;
	Object	element [];

	// This is the (global) counter for the
	// array of specified attributes.
	tagAttributePos = 0;

	// Read the element type name.
	gi = readNmtoken (true);

	// Determine the current content type.
	currentElement = gi;
	element = (Object []) elementInfo.get (gi);
	currentElementContent = getContentType (element, CONTENT_ANY);

	// Read the attributes, if any.
	// After this loop, "c" is the closing delimiter.
	boolean white = tryWhitespace ();
	c = readCh ();
	while (c != '/' && c != '>') {
	    unread (c);
	    if (!white)
		error ("need whitespace between attributes");
	    parseAttribute (gi);
	    white = tryWhitespace ();
	    c = readCh ();
	}

	// Supply any defaulted attributes.
	Enumeration atts = declaredAttributes (element);
	if (atts != null) {
	    String aname;
loop:
	    while (atts.hasMoreElements ()) {
		aname = (String) atts.nextElement ();
		// See if it was specified.
		for (int i = 0; i < tagAttributePos; i++) {
		    if (tagAttributes [i] == aname) {
			continue loop;
		    }
		}
		// I guess not...
		handler.attribute (aname,
				   getAttributeExpandedValue (gi, aname),
				   false);
	    }
	}

	// Figure out if this is a start tag
	// or an empty element, and dispatch an
	// event accordingly.
	switch (c) {
	case '>':
	    handler.startElement (gi);
	    parseContent ();
	    break;
	case '/':
	    require ('>');
	    handler.startElement (gi);
	    handler.endElement (gi);
	    break;
	}

	// Restore the previous state.
	currentElement = oldElement;
	currentElementContent = oldElementContent;
    }


    /**
     * Parse an attribute assignment.