001    package org.hackystat.telemetry.analyzer.language.ast;
002    
003    /**
004     * A constant in telemetry language.
005     * 
006     * @author (Cedric) Qin ZHANG
007     * @version $Id$
008     */
009    public abstract class Constant implements Expression {
010      
011      /**
012       * Gets the value of the constant as a string.
013       * 
014       * @return The string representation of the constant value.
015       */
016      public abstract String getValueString();
017    }