OstermillerUtils
Documentation

DateTimeLexer.lex Source Code

/* DateTimeLexer.java is a generated file.  You probably want to
 * edit DateTimeLexer.lex to make changes.  Use JFlex to generate it.
 * To generate DateTimeLexer.java
 * JFlex may be obtained from
 * <a href="http://jflex.de">the JFlex website</a>.
 * JFlex 1.4 or later is required.
 * Run:<br>
 * jflex  DateTimeLexer.lex<br>
 * You will then have a file called DateTimeLexer.java
 */

/*
 * Copyright (C) 2010-2011 Stephen Ostermiller
 * http://ostermiller.org/contact.pl?regarding=Java+Utilities
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * See LICENSE.txt for details.
 */

package com.Ostermiller.util;

import java.io.*;

/**
 * DateTimeLexer is a Java date time lexer.  Created with JFlex.  An example of how it is used:
 *  <CODE>
 *  <PRE>
 *  DateTimeLexer shredder = new DateTimeLexer(System.in);
 *  DateTimeToken t;
 *  while ((t = shredder.getNextToken()) != null){
 *	  System.out.println(t);
 *  }
 *  </PRE>
 *  </CODE>
 *
 * @see DateTimeToken
 * @author Stephen Ostermiller http://ostermiller.org/contact.pl?regarding=Java+Utilities
 * @since ostermillerutils 1.00.00
 */

%%

%class DateTimeLexer
%apiprivate
%function getToken
%type DateTimeToken
%unicode

%{
    /**
     * Return the next token
     *
     * @return the next token
     * @throws IOException if an error occurs while reading the properties.
     */
    public DateTimeToken getNextToken() throws IOException {
        return getToken();
    }

    private DateTimeToken last = null;
%}

Integer=([0-9]{1,4})
BeginEndWordChar=([:letter:])
MiddleWordChar=([:letter:]|[\-])
RequiredWordChar=[:letter:]
WordWithLetter=({BeginEndWordChar}*{RequiredWordChar}+({MiddleWordChar}{RequiredWordChar})*{BeginEndWordChar}*)
Acronym=(([A-Za-z]\.){2,10})
Word=({WordWithLetter}|{Acronym})
Punctuation=([\:\-\/\,\.\+]+)
Space=([ \t\r\n\f]+)
AbbrYear=([\'\u8216\u8217][0-9]{2})
OrdinalDay=([0-9]{1,2}\.{Space})

%%

<YYINITIAL> {Integer} {
	if (last != null && last.getType() == DateTimeToken.DateTimeTokenType.NUMBER) {
		last = new DateTimeToken(yytext(), DateTimeToken.DateTimeTokenType.ERROR);
		return last;
	} else {
		last = new DateTimeToken(yytext(), DateTimeToken.DateTimeTokenType.NUMBER);
		return last;
	}
}

<YYINITIAL> {Punctuation} {
	last = new DateTimeToken(yytext(), DateTimeToken.DateTimeTokenType.PUNCTUATION);
	return last;
}

<YYINITIAL> {Space} {
	last = new DateTimeToken(yytext(), DateTimeToken.DateTimeTokenType.SPACE);
	return last;
}

<YYINITIAL> {AbbrYear} {
	last = new DateTimeToken(yytext().substring(1), DateTimeToken.DateTimeTokenType.APOS_YEAR);
	return last;
}

<YYINITIAL> {OrdinalDay} {
    String text = yytext();
    int dotIndex = text.indexOf(".");
	last = new DateTimeToken(text.substring(0,dotIndex), DateTimeToken.DateTimeTokenType.ORDINAL_DAY);
	return last;
}

<YYINITIAL> {Word} {
	last = new DateTimeToken(yytext(), DateTimeToken.DateTimeTokenType.WORD);
	return last;
}

<YYINITIAL> [^] {
	last = new DateTimeToken(yytext(), DateTimeToken.DateTimeTokenType.ERROR);
	return last;
}