xmlserializer.java

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            _printer.flush();
    }


    //------------------------------------------//
    // SAX document handler serializing methods //
    //------------------------------------------//


    public void startElement( String tagName, AttributeList attrs )
        throws SAXException
    {
        int          i;
        boolean      preserveSpace;
        ElementState state;
        String       name;
        String       value;

        try {
        if ( _printer == null )
            throw new IllegalStateException( "SER002 No writer supplied for serializer" );

        state = getElementState();
        if ( isDocumentState() ) {
            // If this is the root element handle it differently.
            // If the first root element in the document, serialize
            // the document's DOCTYPE. Space preserving defaults
            // to that of the output format.
            if ( ! _started )
                startDocument( tagName );
        } else {
            // For any other element, if first in parent, then
            // close parent's opening tag and use the parnet's
            // space preserving.
            if ( state.empty )
                _printer.printText( '>' );
            // Must leave CData section first
            if ( state.inCData )
            {
                _printer.printText( "]]>" );
                state.inCData = false;
            }
            // Indent this element on a new line if the first
            // content of the parent element or immediately
            // following an element.
            if ( _indenting && ! state.preserveSpace &&
                 ( state.empty || state.afterElement || state.afterComment) )
                _printer.breakLine();
        }
        preserveSpace = state.preserveSpace;

        // Do not change the current element state yet.
        // This only happens in endElement().

        _printer.printText( '<' );
        _printer.printText( tagName );
        _printer.indent();

        // For each attribute print it's name and value as one part,
        // separated with a space so the element can be broken on
        // multiple lines.
        if ( attrs != null ) {
            for ( i = 0 ; i < attrs.getLength() ; ++i ) {
                _printer.printSpace();
                name = attrs.getName( i );
                value = attrs.getValue( i );
                if ( value != null ) {
                    _printer.printText( name );
                    _printer.printText( "=\"" );
                    printEscaped( value );
                    _printer.printText( '"' );
                }

                // If the attribute xml:space exists, determine whether
                // to preserve spaces in this and child nodes based on
                // its value.
                if ( name.equals( "xml:space" ) ) {
                    if ( value.equals( "preserve" ) )
                        preserveSpace = true;
                    else
                        preserveSpace = _format.getPreserveSpace();
                }
            }
        }
        // Now it's time to enter a new element state
        // with the tag name and space preserving.
        // We still do not change the curent element state.
        state = enterElementState( null, null, tagName, preserveSpace );
        state.doCData = _format.isCDataElement( tagName );
        state.unescaped = _format.isNonEscapingElement( tagName );
        } catch ( IOException except ) {
            throw new SAXException( except );
    }

    }


    public void endElement( String tagName )
        throws SAXException
    {
        endElement( null, null, tagName );
    }



    //------------------------------------------//
    // Generic node serializing methods methods //
    //------------------------------------------//


    /**
     * Called to serialize the document's DOCTYPE by the root element.
     * The document type declaration must name the root element,
     * but the root element is only known when that element is serialized,
     * and not at the start of the document.
     * <p>
     * This method will check if it has not been called before ({@link #_started}),
     * will serialize the document type declaration, and will serialize all
     * pre-root comments and PIs that were accumulated in the document
     * (see {@link #serializePreRoot()}). Pre-root will be serialized even if
     * this is not the first root element of the document.
     */
    protected void startDocument( String rootTagName )
        throws IOException
    {
        int    i;
        String dtd;

        dtd = _printer.leaveDTD();
        if ( ! _started ) {

            if ( ! _format.getOmitXMLDeclaration() ) {
                StringBuffer    buffer;

                // Serialize the document declaration appreaing at the head
                // of very XML document (unless asked not to).
                buffer = new StringBuffer( "<?xml version=\"" );
                if ( _format.getVersion() != null )
                    buffer.append( _format.getVersion() );
                else
                    buffer.append( "1.0" );
                buffer.append( '"' );
                if ( _format.getEncoding() != null ) {
                    buffer.append( " encoding=\"" );
                    buffer.append( _format.getEncoding() );
                    buffer.append( '"' );
                }
                if ( _format.getStandalone() && _docTypeSystemId == null &&
                     _docTypePublicId == null )
                    buffer.append( " standalone=\"yes\"" );
                buffer.append( "?>" );
                _printer.printText( buffer );
                _printer.breakLine();
            }

            if ( ! _format.getOmitDocumentType() ) {
                if ( _docTypeSystemId != null ) {
                    // System identifier must be specified to print DOCTYPE.
                    // If public identifier is specified print 'PUBLIC
                    // <public> <system>', if not, print 'SYSTEM <system>'.
                    _printer.printText( "<!DOCTYPE " );
                    _printer.printText( rootTagName );
                    if ( _docTypePublicId != null ) {
                        _printer.printText( " PUBLIC " );
                        printDoctypeURL( _docTypePublicId );
                        if ( _indenting ) {
                            _printer.breakLine();
                            for ( i = 0 ; i < 18 + rootTagName.length() ; ++i )
                                _printer.printText( " " );
                        } else
                            _printer.printText( " " );
                    printDoctypeURL( _docTypeSystemId );
                    }
                    else {
                        _printer.printText( " SYSTEM " );
                        printDoctypeURL( _docTypeSystemId );
                    }
                    
                    // If we accumulated any DTD contents while printing.
                    // this would be the place to print it.
                    if ( dtd != null && dtd.length() > 0 ) {
                        _printer.printText( " [" );
                        printText( dtd, true, true );
                        _printer.printText( ']' );
                    }
                    
                    _printer.printText( ">" );
                    _printer.breakLine();
                } else if ( dtd != null && dtd.length() > 0 ) {
                    _printer.printText( "<!DOCTYPE " );
                    _printer.printText( rootTagName );
                    _printer.printText( " [" );
                    printText( dtd, true, true );
                    _printer.printText( "]>" );
                    _printer.breakLine();
                }
            }
        }
        _started = true;
        // Always serialize these, even if not te first root element.
        serializePreRoot();
    }


    /**
     * Called to serialize a DOM element. Equivalent to calling {@link
     * #startElement(String, String, String, Attributes)}, {@link #endElement(String, String, String)} and serializing everything
     * inbetween, but better optimized.
     */
    protected void serializeElement( Element elem )
        throws IOException
    {
        Attr         attr;
        NamedNodeMap attrMap;
        int          i;
        Node         child;
        ElementState state;
        boolean      preserveSpace;
        String       name;
        String       value;
        String       tagName;

        tagName = elem.getTagName();
        state = getElementState();
        if ( isDocumentState() ) {
            // If this is the root element handle it differently.
            // If the first root element in the document, serialize
            // the document's DOCTYPE. Space preserving defaults
            // to that of the output format.
            if ( ! _started )
                startDocument( tagName );
        } else {
            // For any other element, if first in parent, then
            // close parent's opening tag and use the parnet's
            // space preserving.
            if ( state.empty )
                _printer.printText( '>' );
            // Must leave CData section first
            if ( state.inCData )
            {
                _printer.printText( "]]>" );
                state.inCData = false;
            }
            // Indent this element on a new line if the first
            // content of the parent element or immediately
            // following an element.
            if ( _indenting && ! state.preserveSpace &&
                 ( state.empty || state.afterElement || state.afterComment) )
                _printer.breakLine();
        }
        preserveSpace = state.preserveSpace;

        // Do not change the current element state yet.
        // This only happens in endElement().

        _printer.printText( '<' );
        _printer.printText( tagName );
        _printer.indent();

        // Lookup the element's attribute, but only print specified
        // attributes. (Unspecified attributes are derived from the DTD.
        // For each attribute print it's name and value as one part,
        // separated with a space so the element can be broken on
        // multiple lines.
        attrMap = elem.getAttributes();
        if ( attrMap != null ) {
            for ( i = 0 ; i < attrMap.getLength() ; ++i ) {
                attr = (Attr) attrMap.item( i );
                name = attr.getName();
                value = attr.getValue();
                if ( value == null )
                    value = "";
                if ( attr.getSpecified() ) {
                    _printer.printSpace();
                    _printer.printText( name );
                    _printer.printText( "=\"" );
                    printEscaped( value );
                    _printer.printText( '"' );
                }
                // If the attribute xml:space exists, determine whether
                // to preserve spaces in this and child nodes based on
                // its value.
                if ( name.equals( "xml:space" ) ) {
                    if ( value.equals( "preserve" ) )
                        preserveSpace = true;
                    else
                        preserveSpace = _format.getPreserveSpace();
                }
            }
        }

        // If element has children, then serialize them, otherwise
        // serialize en empty tag.
        if ( elem.hasChildNodes() ) {
            // Enter an element state, and serialize the children
            // one by one. Finally, end the element.
            state = enterElementState( null, null, tagName, preserveSpace );
            state.doCData = _format.isCDataElement( tagName );
            state.unescaped = _format.isNonEscapingElement( tagName );
            child = elem.getFirstChild();
            while ( child != null ) {
                serializeNode( child );
                child = child.getNextSibling();
            }
            endElementIO( null, null, tagName );
        } else {
            _printer.unindent();
            _printer.printText( "/>" );
            // After element but parent element is no longer empty.
            state.afterElement = true;
            state.afterComment = false;
            state.empty = false;
            if ( isDocumentState() )
                _printer.flush();
        }
    }


    protected String getEntityRef( int ch )
    {
        // Encode special XML characters into the equivalent character references.
        // These five are defined by default for all XML documents.
        switch ( ch ) {
        case '<':
            return "lt";
        case '>':
            return "gt";
        case '"':
            return "quot";
        case '\'':
            return "apos";
        case '&':
            return "amp";
        }
        return null;
    }


    /** Retrieve and remove the namespaces declarations from the list of attributes.
     *
     */
    private Attributes extractNamespaces( Attributes attrs )
        throws SAXException
    {
        AttributesImpl attrsOnly;
        String         rawName;
        int            i;
        int            indexColon;
        String         prefix;
        int            length;

        length = attrs.getLength();
        attrsOnly = new AttributesImpl( attrs );

        for ( i = length - 1 ; i >= 0 ; --i ) {
            rawName = attrsOnly.getQName( i );

            //We have to exclude the namespaces declarations from the attributes
            //Append only when the feature http://xml.org/sax/features/namespace-prefixes"
            //is TRUE
            if ( rawName.startsWith( "xmlns" ) ) {
                indexColon = rawName.indexOf( ':' );

                //is there a prefix
                if ( indexColon != -1 && ( indexColon + 1 ) < rawName.length() )
                    prefix = rawName.substring( indexColon + 1 );
                else
                    prefix = "";

                startPrefixMapping( prefix, attrs.getValue( i ) );
                //Remove it
                attrsOnly.removeAttribute( i );
            }
        }
        return attrsOnly;
    }


}