private void scanXMLDeclOrTextDecl()

in src/main/java/org/apache/sling/scripting/jsp/jasper/xmlparser/XMLEncodingDetector.java [1307:1445]
120 lines of code
37 McCabe index (conditional complexity)

    private void scanXMLDeclOrTextDecl(boolean scanningTextDecl,
				       String[] pseudoAttributeValues) 
                throws IOException, JasperException {

        // pseudo-attribute values
        String version = null;
        String encoding = null;
        String standalone = null;

        // scan pseudo-attributes
        final int STATE_VERSION = 0;
        final int STATE_ENCODING = 1;
        final int STATE_STANDALONE = 2;
        final int STATE_DONE = 3;
        int state = STATE_VERSION;

        boolean dataFoundForTarget = false;
        boolean sawSpace = skipSpaces();
        while (peekChar() != '?') {
            dataFoundForTarget = true;
            String name = scanPseudoAttribute(scanningTextDecl, fString);
            switch (state) {
                case STATE_VERSION: {
                    if (name == fVersionSymbol) { //NOSONAR
                        if (!sawSpace) {
                            reportFatalError(scanningTextDecl
                                       ? "jsp.error.xml.spaceRequiredBeforeVersionInTextDecl"
                                       : "jsp.error.xml.spaceRequiredBeforeVersionInXMLDecl",
                                             null);
                        }
                        version = fString.toString();
                        state = STATE_ENCODING;
                        if (!version.equals("1.0")) {
                            // REVISIT: XML REC says we should throw an error
			    // in such cases.
                            // some may object the throwing of fatalError.
                            err.jspError("jsp.error.xml.versionNotSupported",
					 version);
                        }
                    } else if (name == fEncodingSymbol) { //NOSONAR
                        if (!scanningTextDecl) {
                            err.jspError("jsp.error.xml.versionInfoRequired");
                        }
                        if (!sawSpace) {
                            reportFatalError(scanningTextDecl
                                      ? "jsp.error.xml.spaceRequiredBeforeEncodingInTextDecl"
                                      : "jsp.error.xml.spaceRequiredBeforeEncodingInXMLDecl",
                                             null);
                        }
                        encoding = fString.toString();
                        state = scanningTextDecl ? STATE_DONE : STATE_STANDALONE;
                    } else {
                        if (scanningTextDecl) {
                            err.jspError("jsp.error.xml.encodingDeclRequired");
                        }
                        else {
                            err.jspError("jsp.error.xml.versionInfoRequired");
                        }
                    }
                    break;
                }
                case STATE_ENCODING: {
                    if (name == fEncodingSymbol) { //NOSONAR
                        if (!sawSpace) {
                            reportFatalError(scanningTextDecl
                                      ? "jsp.error.xml.spaceRequiredBeforeEncodingInTextDecl"
                                      : "jsp.error.xml.spaceRequiredBeforeEncodingInXMLDecl",
                                             null);
                        }
                        encoding = fString.toString();
                        state = scanningTextDecl ? STATE_DONE : STATE_STANDALONE;
                        // TODO: check encoding name; set encoding on
                        //       entity scanner
                    } else if (!scanningTextDecl && name == fStandaloneSymbol) { //NOSONAR
                        if (!sawSpace) {
                            err.jspError("jsp.error.xml.spaceRequiredBeforeStandalone");
                        }
                        standalone = fString.toString();
                        state = STATE_DONE;
                        if (!standalone.equals("yes") && !standalone.equals("no")) {
                            err.jspError("jsp.error.xml.sdDeclInvalid");
                        }
                    } else {
                        err.jspError("jsp.error.xml.encodingDeclRequired");
                    }
                    break;
                }
                case STATE_STANDALONE: {
                    if (name == fStandaloneSymbol) { //NOSONAR
                        if (!sawSpace) {
                            err.jspError("jsp.error.xml.spaceRequiredBeforeStandalone");
                        }
                        standalone = fString.toString();
                        state = STATE_DONE;
                        if (!standalone.equals("yes") && !standalone.equals("no")) {
                            err.jspError("jsp.error.xml.sdDeclInvalid");
                        }
                    } else {
			err.jspError("jsp.error.xml.encodingDeclRequired");
                    }
                    break;
                }
                default: {
                    err.jspError("jsp.error.xml.noMorePseudoAttributes");
                }
            }
            sawSpace = skipSpaces();
        }
        // REVISIT: should we remove this error reporting?
        if (scanningTextDecl && state != STATE_DONE) {
            err.jspError("jsp.error.xml.morePseudoAttributes");
        }
        
        // If there is no data in the xml or text decl then we fail to report
	// error for version or encoding info above.
        if (scanningTextDecl) {
            if (!dataFoundForTarget && encoding == null) {
                err.jspError("jsp.error.xml.encodingDeclRequired");
            }
        } else {
            if (!dataFoundForTarget && version == null) {
                err.jspError("jsp.error.xml.versionInfoRequired");
            }
        }

        // end
        if (!skipChar('?')) {
            err.jspError("jsp.error.xml.xmlDeclUnterminated");
        }
        if (!skipChar('>')) {
            err.jspError("jsp.error.xml.xmlDeclUnterminated");

        }
        
        // fill in return array
        pseudoAttributeValues[0] = version;
        pseudoAttributeValues[1] = encoding;
        pseudoAttributeValues[2] = standalone;
    }