public LexicalAnalyzer(String theSource) 
{
            mySource = theSource;
            mySourceLength = theSource.length();
            myCurrentIndex = 0;
            nextLexeme();
}

 public String getLexeme() 
{
            return(myLexemeBeginIndex  >= mySourceLength ?
                   null :
                   mySource.substring(myLexemeBeginIndex, myLexemeEndIndex));
}

 public char getLexemeFirstCharacter() 
{
            return(myLexemeBeginIndex  >= mySourceLength ?
                   '\u0000' :
                   mySource.charAt(myLexemeBeginIndex));
}

 public int getLexemeType() 
{
            return myLexemeType;
}

 public  void nextLexeme() 
{
            int state = 0;
            int commentLevel = 0;
            char c;
            while (state  >= 0) {
                switch (state) {
                    // Looking for a token, quoted string, or tspecial
                case 0:
                    if (myCurrentIndex  >= mySourceLength) {
                        myLexemeType = EOF_LEXEME;
                        myLexemeBeginIndex = mySourceLength;
                        myLexemeEndIndex = mySourceLength;
                        state = -1;
                    } else if (Character.isWhitespace
                               (c = mySource.charAt (myCurrentIndex ++))) {
                        state = 0;
                    } else if (c == '\"') {
                        myLexemeType = QUOTED_STRING_LEXEME;
                        myLexemeBeginIndex = myCurrentIndex;
                        state = 1;
                    } else if (c == '(') {
                        ++ commentLevel;
                        state = 3;
                    } else if (c == '/'  || c == ';' || c == '=' ||
                               c == ')'  || c == '< ' || c == ' >' ||
                               c == '@'  || c == ',' || c == ':' ||
                               c == '\\' || c == '[' || c == ']' ||
                               c == '?') {
                        myLexemeType = TSPECIAL_LEXEME;
                        myLexemeBeginIndex = myCurrentIndex - 1;
                        myLexemeEndIndex = myCurrentIndex;
                        state = -1;
                    } else {
                        myLexemeType = TOKEN_LEXEME;
                        myLexemeBeginIndex = myCurrentIndex - 1;
                        state = 5;
                    }
                    break;
                    // In a quoted string
                case 1:
                    if (myCurrentIndex  >= mySourceLength) {
                        myLexemeType = ILLEGAL_LEXEME;
                        myLexemeBeginIndex = mySourceLength;
                        myLexemeEndIndex = mySourceLength;
                        state = -1;
                    } else if ((c = mySource.charAt (myCurrentIndex ++)) == '\"') {
                        myLexemeEndIndex = myCurrentIndex - 1;
                        state = -1;
                    } else if (c == '\\') {
                        state = 2;
                    } else {
                        state = 1;
                    }
                    break;
                    // In a quoted string, backslash seen
                case 2:
                    if (myCurrentIndex  >= mySourceLength) {
                        myLexemeType = ILLEGAL_LEXEME;
                        myLexemeBeginIndex = mySourceLength;
                        myLexemeEndIndex = mySourceLength;
                        state = -1;
                    } else {
                        ++ myCurrentIndex;
                        state = 1;
                    } break;
                    // In a comment
                case 3: if (myCurrentIndex  >= mySourceLength) {
                    myLexemeType = ILLEGAL_LEXEME;
                    myLexemeBeginIndex = mySourceLength;
                    myLexemeEndIndex = mySourceLength;
                    state = -1;
                } else if ((c = mySource.charAt (myCurrentIndex ++)) == '(') {
                    ++ commentLevel;
                    state = 3;
                } else if (c == ')') {
                    -- commentLevel;
                    state = commentLevel == 0 ? 0 : 3;
                } else if (c == '\\') {
                    state = 4;
                } else { state = 3;
                }
                break;
                // In a comment, backslash seen
                case 4:
                    if (myCurrentIndex  >= mySourceLength) {
                        myLexemeType = ILLEGAL_LEXEME;
                        myLexemeBeginIndex = mySourceLength;
                        myLexemeEndIndex = mySourceLength;
                        state = -1;
                    } else {
                        ++ myCurrentIndex;
                        state = 3;
                    }
                    break;
                    // In a token
                case 5:
                    if (myCurrentIndex  >= mySourceLength) {
                        myLexemeEndIndex = myCurrentIndex;
                        state = -1;
                    } else if (Character.isWhitespace
                               (c = mySource.charAt (myCurrentIndex ++))) {
                        myLexemeEndIndex = myCurrentIndex - 1;
                        state = -1;
                    } else if (c == '\"' || c == '(' || c == '/' ||
                               c == ';'  || c == '=' || c == ')' ||
                               c == '< ' || c == ' >'  || c == '@' ||
                               c == ',' || c == ':' || c == '\\' ||
                               c == '[' || c == ']' || c == '?') {
                        -- myCurrentIndex;
                        myLexemeEndIndex = myCurrentIndex;
                        state = -1;
                    } else {
                        state = 5;
                    }
                    break;
                }
            }
}