literalexpr.java

这是外国一个开源推理机

/*  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.sesame.sail.query;

import java.util.Collection;

import org.openrdf.model.Literal;
import org.openrdf.model.Value;

/**
 **/
public class LiteralExpr implements ValueExpr {

	protected Literal _lit;

	public LiteralExpr(Literal lit) {
		_lit = lit;
	}

	public Value getValue() {
		return _lit;
	}

	public String getString() {
		return _lit.getLabel();
	}

	public void getVariables(Collection variables) {
		// no-op
	}

	public String toString() {
		StringBuffer result = new StringBuffer(100);

		// label
		result.append("\"" + _lit.getLabel() + "\"");

		// language
		if (_lit.getLanguage() != null) {
			result.append("@" + _lit.getLanguage());
		}
				
		// datatype
		if (_lit.getDatatype() != null) {
			result.append("^^<" + _lit.getDatatype().getURI() + ">");
		}

		return result.toString();
	}
}