Class: org.apache.batik.css.parser.Scanner   ©

/*

 ============================================================================
                   The Apache Software License, Version 1.1
 ============================================================================

 Copyright (C) 1999-2003 The Apache Software Foundation. All rights reserved.

 Redistribution and use in source and binary forms, with or without modifica-
 tion, are permitted provided that the following conditions are met:

 1. Redistributions of  source code must  retain the above copyright  notice,
    this list of conditions and the following disclaimer.

 2. Redistributions in binary form must reproduce the above copyright notice,
    this list of conditions and the following disclaimer in the documentation
    and/or other materials provided with the distribution.

 3. The end-user documentation included with the redistribution, if any, must
    include  the following  acknowledgment:  "This product includes  software
    developed  by the  Apache Software Foundation  (http://www.apache.org/)."
    Alternately, this  acknowledgment may  appear in the software itself,  if
    and wherever such third-party acknowledgments normally appear.

 4. The names "Batik" and  "Apache Software Foundation" must  not  be
    used to  endorse or promote  products derived from  this software without
    prior written permission. For written permission, please contact
    apache@apache.org.

 5. Products  derived from this software may not  be called "Apache", nor may
    "Apache" appear  in their name,  without prior written permission  of the
    Apache Software Foundation.

 THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES,
 INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
 FITNESS  FOR A PARTICULAR  PURPOSE ARE  DISCLAIMED.  IN NO  EVENT SHALL  THE
 APACHE SOFTWARE  FOUNDATION  OR ITS CONTRIBUTORS  BE LIABLE FOR  ANY DIRECT,
 INDIRECT, INCIDENTAL, SPECIAL,  EXEMPLARY, OR CONSEQUENTIAL  DAMAGES (INCLU-
 DING, BUT NOT LIMITED TO, PROCUREMENT  OF SUBSTITUTE GOODS OR SERVICES; LOSS
 OF USE, DATA, OR  PROFITS; OR BUSINESS  INTERRUPTION)  HOWEVER CAUSED AND ON
 ANY  THEORY OF LIABILITY,  WHETHER  IN CONTRACT,  STRICT LIABILITY,  OR TORT
 (INCLUDING  NEGLIGENCE OR  OTHERWISE) ARISING IN  ANY WAY OUT OF THE  USE OF
 THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

 This software  consists of voluntary contributions made  by many individuals
 on  behalf of the Apache Software  Foundation. For more  information on the
 Apache Software Foundation, please see <http://www.apache.org/>.

*/

package org.apache.batik.css.parser;

import java.io.IOException;
import java.io.InputStream;
import java.io.Reader;

import org.apache.batik.util.io.NormalizingReader;
import org.apache.batik.util.io.StreamNormalizingReader;
import org.apache.batik.util.io.StringNormalizingReader;

/**
 * This class represents a CSS scanner - an object which decodes CSS lexical
 * units.
 *
 * @author <a href="mailto:stephane@hillion.org">Stephane Hillion</a>
 * @version $Id: Scanner.java,v 1.14 2004/02/16 16:33:54 hillion Exp $
 */
public class Scanner {

    /**
     * The reader.
     */
    protected NormalizingReader reader;

    /**
     * The current char.
     */
    protected int current;

    /**
     * The recording buffer.
     */
    protected char[] buffer = new char[128];

    /**
     * The current position in the buffer.
     */
    protected int position;

    /**
     * The type of the current lexical unit.
     */
    protected int type;

    /**
     * The start offset of the last lexical unit.
     */
    protected int start;

    /**
     * The end offset of the last lexical unit.
     */
    protected int end;

    /**
     * The characters to skip to create the string which represents the
     * current token.
     */
    protected int blankCharacters;

    /**
     * Creates a new Scanner object.
     * @param r The reader to scan.
     */
    public Scanner(Reader r) throws ParseException {
        try {
            reader = new StreamNormalizingReader(r);
Rate            current = nextChar();
        } catch (IOException e) {
            throw new ParseException(e);
        }
    }

    /**
     * Creates a new Scanner object.
     * @param is The input stream to scan.
     * @param enc The encoding to use to decode the input stream, or null.
     */
    public Scanner(InputStream is, String enc) throws ParseException {
        try {
            reader = new StreamNormalizingReader(is, enc);
Rate            current = nextChar();
        } catch (IOException e) {
            throw new ParseException(e);
        }
    }

    /**
     * Creates a new Scanner object.
     * @param r The reader to scan.
     */
    public Scanner(String s) throws ParseException {
        try {
            reader = new StringNormalizingReader(s);
Rate            current = nextChar(); 
        } catch (IOException e) {
            throw new ParseException(e);
        }
    }

    /**
     * Returns the current line.
     */
    public int getLine() {
        return reader.getLine();
    }

    /**
     * Returns the current column.
     */
    public int getColumn() {
        return reader.getColumn();
    }

    /**
     * Returns the buffer used to store the chars.
     */
    public char[] getBuffer() {
        return buffer;
    }

    /**
     * Returns the start offset of the last lexical unit.
     */
    public int getStart() {
        return start;
    }

    /**
     * Returns the end offset of the last lexical unit.
     */
    public int getEnd() {
        return end;
    }

    /**
     * Clears the buffer.
     */
    public void clearBuffer() {
        if (position <= 0) {
            position = 0;
        } else {
            buffer[0] = buffer[position-1];
            position = 1;
        }
    }

    /**
     * The current lexical unit type like defined in LexicalUnits.
     */
    public int getType() {
        return type;
    }

    /**
     * Returns the string representation of the current lexical unit.
     */
    public String getStringValue() {
        return new String(buffer, start, end - start);
    }

    /**
     * Scans a @rule value. This method assumes that the current
     * lexical unit is a at keyword.
     */
    public void scanAtRule() throws ParseException {
        try {
            // waiting for EOF, ';' or '{'
            loop: for (;;) {
                switch (current) {
                case '{':
                    int brackets = 1;
                    for (;;) {
Rate                        nextChar();
                        switch (current) {
                        case '}':
                            if (--brackets > 0) {
                                break;
                            }
                        case -1:
                            break loop;
                        case '{':
                            brackets++;
                        }
                    }
                case -1:
                case ';':
                    break loop;
                }
Rate                nextChar();
            }
            end = position;
        } catch (IOException e) {
            throw new ParseException(e);
        }
    }
    
    /**
     * Returns the next token.
     */
    public int next() throws ParseException {
        blankCharacters = 0;
        start = position - 1;
        nextToken();
        end = position - endGap();
        return type;
    }

    /**
     * Returns the end gap of the current lexical unit.
     */
    protected int endGap() {
        int result = (current == -1) ? 0 : 1;
        switch (type) {
        case LexicalUnits.FUNCTION:
        case LexicalUnits.STRING:
        case LexicalUnits.S:
        case LexicalUnits.PERCENTAGE:
            result += 1;
            break;
        case LexicalUnits.COMMENT:
        case LexicalUnits.HZ:
        case LexicalUnits.EM:
        case LexicalUnits.EX:
        case LexicalUnits.PC:
        case LexicalUnits.PT:
        case LexicalUnits.PX:
        case LexicalUnits.CM:
        case LexicalUnits.MM:
        case LexicalUnits.IN:
        case LexicalUnits.MS:
            result += 2;
            break;
        case LexicalUnits.KHZ:
        case LexicalUnits.DEG:
        case LexicalUnits.RAD:
            result += 3;
            break;
        case LexicalUnits.GRAD:
            result += 4;
        }
        return result + blankCharacters;
    }

    /**
     * Returns the next token.
     */
    protected void nextToken() throws ParseException {
        try {
            switch (current) {
            case -1:
                type = LexicalUnits.EOF;
                return;
            case '{':
Rate                nextChar();
                type = LexicalUnits.LEFT_CURLY_BRACE;
                return;
            case '}':
Rate                nextChar();
                type = LexicalUnits.RIGHT_CURLY_BRACE;
                return;
            case '=':
Rate                nextChar();
                type = LexicalUnits.EQUAL;
                return;
            case '+':
Rate                nextChar();
                type = LexicalUnits.PLUS;
                return;
            case ',':
Rate                nextChar();
                type = LexicalUnits.COMMA;
                return;
            case ';':
Rate                nextChar();
                type = LexicalUnits.SEMI_COLON;
                return;
            case '>':
Rate                nextChar();
                type = LexicalUnits.PRECEDE;
                return;
            case '[':
Rate                nextChar();
                type = LexicalUnits.LEFT_BRACKET;
                return;
            case ']':
Rate                nextChar();
                type = LexicalUnits.RIGHT_BRACKET;
                return;
            case '*':
Rate                nextChar();
                type = LexicalUnits.ANY;
                return;
            case '(':
Rate                nextChar();
                type = LexicalUnits.LEFT_BRACE;
                return;
            case ')':
Rate                nextChar();
                type = LexicalUnits.RIGHT_BRACE;
                return;
            case ':':
Rate                nextChar();
                type = LexicalUnits.COLON;
                return;
            case ' ':
            case '\t':
            case '\r':
            case '\n':
            case '\f':
                do {
Rate                    nextChar();
                } while (ScannerUtilities.isCSSSpace((char)current));
                type = LexicalUnits.SPACE;
                return;
            case '/':
Rate                nextChar();
                if (current != '*') {
                    type = LexicalUnits.DIVIDE;
                    return;
                }
                // Comment
Rate                nextChar();
                start = position - 1;
                do {
                    while (current != -1 && current != '*') {
Rate                        nextChar();
                    }
                    do {
Rate                        nextChar();
                    } while (current != -1 && current == '*');
                } while (current != -1 && current != '/');
                if (current == -1) {
                    throw new ParseException("eof",
                                             reader.getLine(),
                                             reader.getColumn());
                }
Rate                nextChar();
                type = LexicalUnits.COMMENT; 
                return;
            case '\'': // String1
                type = string1();
                return;
            case '"': // String2
                type = string2();
                return;
            case '<':
Rate                nextChar();
                if (current != '!') {
                    throw new ParseException("character",
                                             reader.getLine(),
                                             reader.getColumn());
                }
Rate                nextChar();
                if (current == '-') {
Rate                    nextChar();
                    if (current == '-') {
Rate                        nextChar();
                        type = LexicalUnits.CDO;
                        return;
                    }
                }
                throw new ParseException("character",
                                         reader.getLine(),
                                         reader.getColumn());
            case '-':
Rate                nextChar();
                if (current != '-') {
                    type = LexicalUnits.MINUS;
                    return;
                }
Rate                nextChar();
                if (current == '>') {
Rate                    nextChar();
                    type = LexicalUnits.CDC;
                    return;
                }
                throw new ParseException("character",
                                         reader.getLine(),
                                         reader.getColumn());
            case '|':
Rate                nextChar();
                if (current == '=') {
Rate                    nextChar();
                    type = LexicalUnits.DASHMATCH;
                    return;
                }
                throw new ParseException("character",
                                         reader.getLine(),
                                         reader.getColumn());
            case '~':
Rate                nextChar();
                if (current == '=') {
Rate                    nextChar();
                    type = LexicalUnits.INCLUDES;
                    return;
                }
                throw new ParseException("character",
                                         reader.getLine(),
                                         reader.getColumn());
            case '#':
Rate                nextChar();
                if (ScannerUtilities.isCSSNameCharacter((char)current)) {
                    start = position - 1;
                    do {
Rate                        nextChar();
                        if (current == '\\') {
Rate                            nextChar();
                            escape();
                        }
                    } while (current != -1 &&
                             ScannerUtilities.isCSSNameCharacter
                                 ((char)current));
                    type = LexicalUnits.HASH;
                    return;
                }
                throw new ParseException("character",
                                         reader.getLine(),
                                         reader.getColumn());
            case '@':
Rate                nextChar();
                switch (current) {
                case 'c':
                case 'C':
                    start = position - 1;
Rate                    if (isEqualIgnoreCase(nextChar(), 'h') &&
                        isEqualIgnoreCase(nextChar(), 'a') &&
                        isEqualIgnoreCase(nextChar(), 'r') &&
                        isEqualIgnoreCase(nextChar(), 's') &&
                        isEqualIgnoreCase(nextChar(), 'e') &&
                        isEqualIgnoreCase(nextChar(), 't')) {
Rate                        nextChar();
                        type = LexicalUnits.CHARSET_SYMBOL;
                        return;
                    }
                    break;
                case 'f':
                case 'F':
                    start = position - 1;
Rate                    if (isEqualIgnoreCase(nextChar(), 'o') &&
                        isEqualIgnoreCase(nextChar(), 'n') &&
                        isEqualIgnoreCase(nextChar(), 't') &&
                        isEqualIgnoreCase(nextChar(), '-') &&
                        isEqualIgnoreCase(nextChar(), 'f') &&
                        isEqualIgnoreCase(nextChar(), 'a') &&
                        isEqualIgnoreCase(nextChar(), 'c') &&
                        isEqualIgnoreCase(nextChar(), 'e')) {
Rate                        nextChar();
                        type = LexicalUnits.FONT_FACE_SYMBOL;
                        return;
                    }
                    break;
                case 'i':
                case 'I':
                    start = position - 1;
Rate                    if (isEqualIgnoreCase(nextChar(), 'm') &&
                        isEqualIgnoreCase(nextChar(), 'p') &&
                        isEqualIgnoreCase(nextChar(), 'o') &&
                        isEqualIgnoreCase(nextChar(), 'r') &&
                        isEqualIgnoreCase(nextChar(), 't')) {
Rate                        nextChar();
                        type = LexicalUnits.IMPORT_SYMBOL;
                        return;
                    }
                    break;
                case 'm':
                case 'M':
                    start = position - 1;
Rate                    if (isEqualIgnoreCase(nextChar(), 'e') &&
                        isEqualIgnoreCase(nextChar(), 'd') &&
                        isEqualIgnoreCase(nextChar(), 'i') &&
                        isEqualIgnoreCase(nextChar(), 'a')) {
Rate                        nextChar();
                        type = LexicalUnits.MEDIA_SYMBOL;
                        return;
                    }
                    break;
                case 'p':
                case 'P':
                    start = position - 1;
Rate                    if (isEqualIgnoreCase(nextChar(), 'a') &&
                        isEqualIgnoreCase(nextChar(), 'g') &&
                        isEqualIgnoreCase(nextChar(), 'e')) {
Rate                        nextChar();
                        type = LexicalUnits.PAGE_SYMBOL;
                        return;
                    }
                    break;
                default:
                    if (!ScannerUtilities.isCSSIdentifierStartCharacter
                        ((char)current)) {
                        throw new ParseException("identifier.character",
                                                 reader.getLine(),
                                                 reader.getColumn());
                    }
                    start = position - 1;
                }
                do {
Rate                    nextChar();
                    if (current == '\\') {
Rate                        nextChar();
                        escape();
                    }
                } while (current != -1 &&
                         ScannerUtilities.isCSSNameCharacter((char)current));
                type = LexicalUnits.AT_KEYWORD;
                return;
            case '!':
                do {
Rate                    nextChar();
                } while (current != -1 &&
                         ScannerUtilities.isCSSSpace((char)current));
Rate                if (isEqualIgnoreCase(current, 'i') &&
                    isEqualIgnoreCase(nextChar(), 'm') &&
                    isEqualIgnoreCase(nextChar(), 'p') &&
                    isEqualIgnoreCase(nextChar(), 'o') &&
                    isEqualIgnoreCase(nextChar(), 'r') &&
                    isEqualIgnoreCase(nextChar(), 't') &&
                    isEqualIgnoreCase(nextChar(), 'a') &&
                    isEqualIgnoreCase(nextChar(), 'n') &&
                    isEqualIgnoreCase(nextChar(), 't')) {
Rate                    nextChar();
                    type = LexicalUnits.IMPORTANT_SYMBOL;
                    return;
                }
                if (current == -1) {
                    throw new ParseException("eof",
                                             reader.getLine(),
                                             reader.getColumn());
                } else {
                    throw new ParseException("character",
                                             reader.getLine(),
                                             reader.getColumn());
                }
            case '0': case '1': case '2': case '3': case '4':
            case '5': case '6': case '7': case '8': case '9':
                type = number();
                return;
            case '.':
Rate                switch (nextChar()) {
                case '0': case '1': case '2': case '3': case '4':
                case '5': case '6': case '7': case '8': case '9':
                    type = dotNumber();
                    return;
                default:
                    type = LexicalUnits.DOT;
                    return;
                }
            case 'u':
            case 'U':
Rate                nextChar();
                switch (current) {
                case '+':
                    boolean range = false;
                    for (int i = 0; i < 6; i++) {
Rate                        nextChar();
                        switch (current) {
                        case '?':
                            range = true;
                            break;
                        default:
                            if (range &&
                            !ScannerUtilities.isCSSHexadecimalCharacter
                                ((char)current)) {
                                throw new ParseException("character",
                                                         reader.getLine(),
                                                         reader.getColumn());
                            }
                        }
                    }
Rate                    nextChar();
                    if (range) {
                        type = LexicalUnits.UNICODE_RANGE;
                        return;
                    }
                    if (current == '-') {
Rate                        nextChar();
                        if (!ScannerUtilities.isCSSHexadecimalCharacter
                            ((char)current)) {
                            throw new ParseException("character",
                                                     reader.getLine(),
                                                     reader.getColumn());
                        }
Rate                        nextChar();
                        if (!ScannerUtilities.isCSSHexadecimalCharacter
                            ((char)current)) {
                            type = LexicalUnits.UNICODE_RANGE;
                            return;
                        }
Rate                        nextChar();
                        if (!ScannerUtilities.isCSSHexadecimalCharacter
                            ((char)current)) {
                            type = LexicalUnits.UNICODE_RANGE;
                            return;
                        }
Rate                        nextChar();
                        if (!ScannerUtilities.isCSSHexadecimalCharacter
                            ((char)current)) {
                            type = LexicalUnits.UNICODE_RANGE;
                            return;
                        }
Rate                        nextChar();
                        if (!ScannerUtilities.isCSSHexadecimalCharacter
                            ((char)current)) {
                            type = LexicalUnits.UNICODE_RANGE;
                            return;
                        }
Rate                        nextChar();
                        if (!ScannerUtilities.isCSSHexadecimalCharacter
                            ((char)current)) {
                            type = LexicalUnits.UNICODE_RANGE;
                            return;
                        }
Rate                        nextChar();
                        type = LexicalUnits.UNICODE_RANGE;
                        return;
                    }
                case 'r':
                case 'R':
Rate                    nextChar();
                    switch (current) {
                    case 'l':
                    case 'L':
Rate                        nextChar();
                        switch (current) {
                        case '(':
                            do {
Rate                                nextChar();
                            } while (current != -1 &&
                                     ScannerUtilities.isCSSSpace
                                     ((char)current));
                            switch (current) {
                            case '\'':
                                string1();
                                blankCharacters += 2;
                                while (current != -1 &&
                                       ScannerUtilities.isCSSSpace
                                       ((char)current)) {
                                    blankCharacters++;
Rate                                    nextChar();
                                }
                                if (current == -1) {
                                    throw new ParseException
                                        ("eof",
                                         reader.getLine(),
                                         reader.getColumn());
                                }
                                if (current != ')') {
                                    throw new ParseException
                                        ("character",
                                         reader.getLine(),
                                         reader.getColumn());
                                }
Rate                                nextChar();
                                type = LexicalUnits.URI;
                                return;
                            case '"':
                                string2();
                                blankCharacters += 2;
                                while (current != -1 &&
                                       ScannerUtilities.isCSSSpace
                                       ((char)current)) {
                                    blankCharacters++;
Rate                                    nextChar();
                                }
                                if (current == -1) {
                                    throw new ParseException
                                        ("eof",
                                         reader.getLine(),
                                         reader.getColumn());
                                }
                                if (current != ')') {
                                    throw new ParseException
                                        ("character",
                                         reader.getLine(),
                                         reader.getColumn());
                                }
Rate                                nextChar();
                                type = LexicalUnits.URI;
                                return;
                            case ')':
                                throw new ParseException("character",
                                                         reader.getLine(),
                                                         reader.getColumn());
                            default:
                                if (!ScannerUtilities.isCSSURICharacter
                                    ((char)current)) {
                                    throw new ParseException
                                        ("character",
                                         reader.getLine(),
                                         reader.getColumn());
                                }
                                start = position - 1;
                                do {
Rate                                    nextChar();
                                } while (current != -1 &&
                                      ScannerUtilities.isCSSURICharacter
                                         ((char)current));
                                blankCharacters++;
                                while (current != -1 &&
                                       ScannerUtilities.isCSSSpace
                                       ((char)current)) {
                                    blankCharacters++;
Rate                                    nextChar();
                                }
                                if (current == -1) {
                                    throw new ParseException
                                        ("eof",
                                         reader.getLine(),
                                         reader.getColumn());
                                }
                                if (current != ')') {
                                    throw new ParseException
                                        ("character",
                                         reader.getLine(),
                                         reader.getColumn());
                                }
Rate                                nextChar();
                                type = LexicalUnits.URI;
                                return;
                            }
                        }
                    }
                }
                while (current != -1 &&
                       ScannerUtilities.isCSSNameCharacter((char)current)) {
Rate                    nextChar();
                }
                if (current == '(') {
Rate                    nextChar();
                    type = LexicalUnits.FUNCTION;
                    return;
                }
                type = LexicalUnits.IDENTIFIER;
                return;
            default:
                if (ScannerUtilities.isCSSIdentifierStartCharacter
                    ((char)current)) {
                    // Identifier
                    do {
Rate                        nextChar();
                        if (current == '\\') {
Rate                            nextChar();
                            escape();
                        }
                    } while (current != -1 && 
                             ScannerUtilities.isCSSNameCharacter
                             ((char)current));
                    if (current == '(') {
Rate                        nextChar();
                        type = LexicalUnits.FUNCTION;
                        return;
                    }
                    type = LexicalUnits.IDENTIFIER;
                    return;
                }
Rate                nextChar();
                throw new ParseException("identifier.character",
                                         reader.getLine(),
                                         reader.getColumn());
            }
        } catch (IOException e) {
            throw new ParseException(e);
        }
    }

    /**
     * Scans a single quoted string.
     */
    protected int string1() throws IOException {
Rate        nextChar();
        start = position - 1;
        loop: for (;;) {
Rate            switch (nextChar()) {
            case -1:
                throw new ParseException("eof",
                                         reader.getLine(),
                                         reader.getColumn());
            case '\'':
                break loop;
            case '"':
                break;
            case '\\':
Rate                switch (nextChar()) {
                case '\n':
                case '\f':
                    break;
                default:
                    escape();
                }
                break;
            default:
                if (!ScannerUtilities.isCSSStringCharacter((char)current)) {
                    throw new ParseException("character",
                                             reader.getLine(),
                                             reader.getColumn());
                }
            }
        }
Rate        nextChar();
        return LexicalUnits.STRING;
    }

    /**
     * Scans a double quoted string.
     */
    protected int string2() throws IOException {
Rate        nextChar();
        start = position - 1;
        loop: for (;;) {
Rate            switch (nextChar()) {
            case -1:
                throw new ParseException("eof",
                                         reader.getLine(),
                                         reader.getColumn());
            case '\'':
                break;
            case '"':
                break loop;
            case '\\':
Rate                switch (nextChar()) {
                case '\n':
                case '\f':
                    break;
                default:
                    escape();
                }
                break;
            default:
                if (!ScannerUtilities.isCSSStringCharacter((char)current)) {
                    throw new ParseException("character",
                                             reader.getLine(),
                                             reader.getColumn());
                }
            }
        }
Rate        nextChar();
        return LexicalUnits.STRING;
    }

    /**
     * Scans a number.
     */
    protected int number() throws IOException {
        loop: for (;;) {
Rate            switch (nextChar()) {
            case '.':
Rate                switch (nextChar()) {
                case '0': case '1': case '2': case '3': case '4':
                case '5': case '6': case '7': case '8': case '9':
                    return dotNumber();
                }
                throw new ParseException("character",
                                         reader.getLine(),
                                         reader.getColumn());
            default:
                break loop;
            case '0': case '1': case '2': case '3': case '4':
            case '5': case '6': case '7': case '8': case '9':
            }
        }
        return numberUnit(true);
    }        

    /**
     * Scans the decimal part of a number.
     */
    protected int dotNumber() throws IOException {
        loop: for (;;) {
Rate            switch (nextChar()) {
            default:
                break loop;
            case '0': case '1': case '2': case '3': case '4':
            case '5': case '6': case '7': case '8': case '9':
            }
        }
        return numberUnit(false);
    }

    /**
     * Scans the unit of a number.
     */
    protected int numberUnit(boolean integer) throws IOException {
        switch (current) {
        case '%':
Rate            nextChar();
            return LexicalUnits.PERCENTAGE;
        case 'c':
        case 'C':
Rate            switch(nextChar()) {
            case 'm':
            case 'M':
Rate                nextChar();
                if (current != -1 &&
                    ScannerUtilities.isCSSNameCharacter((char)current)) {
                    do {
Rate                        nextChar();
                    } while (current != -1 &&
                             ScannerUtilities.isCSSNameCharacter
                             ((char)current));
                    return LexicalUnits.DIMENSION;
                }
                return LexicalUnits.CM;
            default:
                while (current != -1 &&
                       ScannerUtilities.isCSSNameCharacter((char)current)) {
Rate                    nextChar();
                }
                return LexicalUnits.DIMENSION;
            }
        case 'd':
        case 'D':
Rate            switch(nextChar()) {
            case 'e':
            case 'E':
Rate                switch(nextChar()) {
                case 'g':
                case 'G':
Rate                    nextChar();
                    if (current != -1 &&
                        ScannerUtilities.isCSSNameCharacter((char)current)) {
                        do {
Rate                            nextChar();
                        } while (current != -1 &&
                                 ScannerUtilities.isCSSNameCharacter
                                 ((char)current));
                        return LexicalUnits.DIMENSION;
                    }
                    return LexicalUnits.DEG;
                }
            default:
                while (current != -1 &&
                       ScannerUtilities.isCSSNameCharacter((char)current)) {
Rate                    nextChar();
                }
                return LexicalUnits.DIMENSION;
            }
        case 'e':
        case 'E':
Rate            switch(nextChar()) {
            case 'm':
            case 'M':
Rate                nextChar();
                if (current != -1 &&
                    ScannerUtilities.isCSSNameCharacter((char)current)) {
                    do {
Rate                        nextChar();
                    } while (current != -1 &&
                             ScannerUtilities.isCSSNameCharacter
                             ((char)current));
                    return LexicalUnits.DIMENSION;
                }
                return LexicalUnits.EM;
            case 'x':
            case 'X':
Rate                nextChar();
                if (current != -1 &&
                    ScannerUtilities.isCSSNameCharacter((char)current)) {
                    do {
Rate                        nextChar();
                    } while (current != -1 &&
                             ScannerUtilities.isCSSNameCharacter
                             ((char)current));
                    return LexicalUnits.DIMENSION;
                }
                return LexicalUnits.EX;
            default:
                while (current != -1 &&
                       ScannerUtilities.isCSSNameCharacter((char)current)) {
Rate                    nextChar();
                }
                return LexicalUnits.DIMENSION;
            }
        case 'g':
        case 'G':
Rate            switch(nextChar()) {
            case 'r':
            case 'R':
Rate                switch(nextChar()) {
                case 'a':
                case 'A':
Rate                    switch(nextChar()) {
                    case 'd':
                    case 'D':
Rate                        nextChar();
                        if (current != -1 &&
                            ScannerUtilities.isCSSNameCharacter
                            ((char)current)) {
                            do {
Rate                                nextChar();
                            } while (current != -1 &&
                                     ScannerUtilities.isCSSNameCharacter
                                     ((char)current));
                            return LexicalUnits.DIMENSION;
                        }
                        return LexicalUnits.GRAD;
                    }
                }
            default:
                while (current != -1 &&
                       ScannerUtilities.isCSSNameCharacter((char)current)) {
Rate                    nextChar();
                }
                return LexicalUnits.DIMENSION;
            }
        case 'h':
        case 'H':
Rate            nextChar();
            switch(current) {
            case 'z':
            case 'Z':
Rate                nextChar();
                if (current != -1 &&
                    ScannerUtilities.isCSSNameCharacter((char)current)) {
                    do {
Rate                        nextChar();
                    } while (current != -1 &&
                             ScannerUtilities.isCSSNameCharacter
                             ((char)current));
                    return LexicalUnits.DIMENSION;
                }
                return LexicalUnits.HZ;
            default:
                while (current != -1 &&
                       ScannerUtilities.isCSSNameCharacter((char)current)) {
Rate                    nextChar();
                }
                return LexicalUnits.DIMENSION;
            }
        case 'i':
        case 'I':
Rate            switch(nextChar()) {
            case 'n':
            case 'N':
Rate                nextChar();
                if (current != -1 &&
                    ScannerUtilities.isCSSNameCharacter((char)current)) {
                    do {
Rate                        nextChar();
                    } while (current != -1 &&
                             ScannerUtilities.isCSSNameCharacter
                             ((char)current));
                    return LexicalUnits.DIMENSION;
                }
                return LexicalUnits.IN;
            default:
                while (current != -1 &&
                       ScannerUtilities.isCSSNameCharacter((char)current)) {
Rate                    nextChar();
                }
                return LexicalUnits.DIMENSION;
            }
        case 'k':
        case 'K':
Rate            switch(nextChar()) {
            case 'h':
            case 'H':
Rate                switch(nextChar()) {
                case 'z':
                case 'Z':
Rate                    nextChar();
                    if (current != -1 &&
                        ScannerUtilities.isCSSNameCharacter((char)current)) {
                        do {
Rate                            nextChar();
                        } while (current != -1 &&
                                 ScannerUtilities.isCSSNameCharacter
                                 ((char)current));
                        return LexicalUnits.DIMENSION;
                    }
                    return LexicalUnits.KHZ;
                }
            default:
                while (current != -1 &&
                       ScannerUtilities.isCSSNameCharacter((char)current)) {
Rate                    nextChar();
                }
                return LexicalUnits.DIMENSION;
            }
        case 'm':
        case 'M':
Rate            switch(nextChar()) {
            case 'm':
            case 'M':
Rate                nextChar();
                if (current != -1 &&
                    ScannerUtilities.isCSSNameCharacter((char)current)) {
                    do {
Rate                        nextChar();
                    } while (current != -1 &&
                             ScannerUtilities.isCSSNameCharacter
                             ((char)current));
                    return LexicalUnits.DIMENSION;
                }
                return LexicalUnits.MM;
            case 's':
            case 'S':
Rate                nextChar();
                if (current != -1 &&
                    ScannerUtilities.isCSSNameCharacter((char)current)) {
                    do {
Rate                        nextChar();
                    } while (current != -1 &&
                             ScannerUtilities.isCSSNameCharacter
                             ((char)current));
                    return LexicalUnits.DIMENSION;
                }
                return LexicalUnits.MS;
            default:
                while (current != -1 &&
                       ScannerUtilities.isCSSNameCharacter((char)current)) {
Rate                    nextChar();
                }
                return LexicalUnits.DIMENSION;
            }
        case 'p':
        case 'P':
Rate            switch(nextChar()) {
            case 'c':
            case 'C':
Rate                nextChar();
                if (current != -1 &&
                    ScannerUtilities.isCSSNameCharacter((char)current)) {
                    do {
Rate                        nextChar();
                    } while (current != -1 &&
                             ScannerUtilities.isCSSNameCharacter
                             ((char)current));
                    return LexicalUnits.DIMENSION;
                }
                return LexicalUnits.PC;
            case 't':
            case 'T':
Rate                nextChar();
                if (current != -1 &&
                    ScannerUtilities.isCSSNameCharacter((char)current)) {
                    do {
Rate                        nextChar();
                    } while (current != -1 &&
                             ScannerUtilities.isCSSNameCharacter
                             ((char)current));
                    return LexicalUnits.DIMENSION;
                }
                return LexicalUnits.PT;
            case 'x':
            case 'X':
Rate                nextChar();
                if (current != -1 &&
                    ScannerUtilities.isCSSNameCharacter((char)current)) {
                    do {
Rate                        nextChar();
                    } while (current != -1 &&
                             ScannerUtilities.isCSSNameCharacter
                             ((char)current));
                    return LexicalUnits.DIMENSION;
                }
                return LexicalUnits.PX;
            default:
                while (current != -1 &&
                       ScannerUtilities.isCSSNameCharacter((char)current)) {
Rate                    nextChar();
                }
                return LexicalUnits.DIMENSION;
            }            
        case 'r':
        case 'R':
Rate            switch(nextChar()) {
            case 'a':
            case 'A':
Rate                switch(nextChar()) {
                case 'd':
                case 'D':
Rate                    nextChar();
                    if (current != -1 &&
                        ScannerUtilities.isCSSNameCharacter((char)current)) {
                        do {
Rate                            nextChar();
                        } while (current != -1 &&
                                 ScannerUtilities.isCSSNameCharacter
                                 ((char)current));
                        return LexicalUnits.DIMENSION;
                    }
                    return LexicalUnits.RAD;
                }
            default:
                while (current != -1 &&
                       ScannerUtilities.isCSSNameCharacter((char)current)) {
Rate                    nextChar();
                }
                return LexicalUnits.DIMENSION;
            }
        case 's':
        case 'S':
Rate            nextChar();
            return LexicalUnits.S;
        default:
            if (current != -1 &&
                ScannerUtilities.isCSSIdentifierStartCharacter
                ((char)current)) {
                do {
Rate                    nextChar();
                } while (current != -1 &&
                         ScannerUtilities.isCSSNameCharacter((char)current));
                return LexicalUnits.DIMENSION;
            }
            return (integer) ? LexicalUnits.INTEGER : LexicalUnits.REAL;
        }
    }

    /**
     * Scans an escape sequence, if one.
     */
    protected void escape() throws IOException {
        if (ScannerUtilities.isCSSHexadecimalCharacter((char)current)) {
Rate            nextChar();
            if (!ScannerUtilities.isCSSHexadecimalCharacter((char)current)) {
                if (ScannerUtilities.isCSSSpace((char)current)) {
Rate                    nextChar();
                }
                return;
            }
Rate            nextChar();
            if (!ScannerUtilities.isCSSHexadecimalCharacter((char)current)) {
                if (ScannerUtilities.isCSSSpace((char)current)) {
Rate                    nextChar();
                }
                return;
            }
Rate            nextChar();
            if (!ScannerUtilities.isCSSHexadecimalCharacter((char)current)) {
                if (ScannerUtilities.isCSSSpace((char)current)) {
Rate                    nextChar();
                }
                return;
            }
Rate            nextChar();
            if (!ScannerUtilities.isCSSHexadecimalCharacter((char)current)) {
                if (ScannerUtilities.isCSSSpace((char)current)) {
Rate                    nextChar();
                }
                return;
            }
Rate            nextChar();
            if (!ScannerUtilities.isCSSHexadecimalCharacter((char)current)) {
                if (ScannerUtilities.isCSSSpace((char)current)) {
Rate                    nextChar();
                }
                return;
            }
        }
        if ((current >= ' ' && current <= '~') || current >= 128) {
Rate            nextChar();
            return;
        }
        throw new ParseException("character",
                                 reader.getLine(),
                                 reader.getColumn());
    }

    /**
     * Compares the given int with the given character, ignoring case.
     */
    protected static boolean isEqualIgnoreCase(int i, char c) {
        return (i == -1) ? false : Character.toLowerCase((char)i) == c;
    }

    /**
     * Sets the value of the current char to the next character or -1 if the
     * end of stream has been reached.
     */
    protected int nextChar() throws IOException {
        current = reader.read();

        if (current == -1) {
            return current;
        }

        if (position == buffer.length) {
            char[] t = new char[position * 3 / 2];
            for (int i = 0; i < position; i++) {
                t[i] = buffer[i];
            }
            buffer = t;
        }

        return buffer[position++] = (char)current;
    }
}