asciiutil.java

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/*  Sesame - Storage and Querying architecture for RDF and RDF Schema
 *  Copyright (C) 2001-2005 Aduna
 *
 *  Contact: 
 *  	Aduna
 *  	Prinses Julianaplein 14 b
 *  	3817 CS Amersfoort
 *  	The Netherlands
 *  	tel. [phone]
 *  	fax. [phone]
 *
 *  	http://aduna.biz/
 *  	http://www.openrdf.org/
 *  
 *  This library is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU Lesser General Public
 *  License as published by the Free Software Foundation; either
 *  version 2.1 of the License, or (at your option) any later version.
 *
 *  This library 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
 *  Lesser General Public License for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public
 *  License along with this library; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

package org.openrdf.util;

/**
 * Utility methods for ASCII character checking.
 **/
public class ASCIIUtil {

/*------------------------------------------------------+
| Methods                                               |
+------------------------------------------------------*/

	/**
	 * Checks whether the supplied character is a letter or number.
	 * @see #isLetter
	 * @see #isNumber
	 **/
	public static boolean isLetterOrNumber(int c) {
		return isLetter(c) || isNumber(c);
	}

	/**
	 * Checks whether the supplied character is a letter.
	 **/
	public static boolean isLetter(int c) {
		return isUpperCaseLetter(c) || isLowerCaseLetter(c);
	}

	/**
	 * Checks whether the supplied character is an upper-case letter.
	 **/
	public static boolean isUpperCaseLetter(int c) {
		return (c >= 65 && c <= 90); // A - Z
	}

	/**
	 * Checks whether the supplied character is an lower-case letter.
	 **/
	public static boolean isLowerCaseLetter(int c) {
		return (c >= 97 && c <= 122);  // a - z
	}

	/**
	 * Checks whether the supplied character is a number
	 **/
	public static boolean isNumber(int c) {
		return (c >= 48 && c <= 57); // 0 - 9
	}
}