/*
* JMEP - Java Mathematical Expression Parser.
* Copyright (C) 1999 Jo Desmet
*
* 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 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
*
* You can contact the Original submitter of this library by
* email at: Jo_Desmet@yahoo.com.
*
*/
package com.iabcinc.jmep.hooks;
/**
* Interface that defines a skeleton for a Variable call-back adaptor.
* It should be implemented in order to use it with the addVariable method of
* Environment. A way to accomplish this is by using in-line adaptor classes:<P>
*<ul><pre><code>oEnv.addVariable("time",
* new Variable() {
* public Object getValue() {
* // Call a method from containing class:
* return new Double(System.currentTimeMillis()/1000.0);
* }
* }
*);</code></pre></ul>
*
* @see com.iabcinc.jmep.Environment
*/
public interface Variable {
/**
* Defines the variable's behaviour. As no problems could be expected from
* getting a known variable it can be expected to always return a legal
* value, hence the return value should be never <code>null</code>.
* @param contextID
* @return the variable contents. Supported return types are <code>String</code>,
* <code>Integer</code> and <code>Double</code>.
*/
public int getValue (int[] ifInt, float[] ifFloat, Object[] ifObject, int contextID);
}