/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.apache.commons.jexl;

import java.util.Map;

/**
 * Holds a Map of variables which are referenced in a JEXL expression.
 *
 *  @since 1.0
 *  
 *  @version $Id$
 */
public interface JexlContext {
    /**
     * Replaces variables in a JexlContext with the variables contained
     * in the supplied Map.  When setVars() is called on a JexlContext,
     * it clears the current Map and puts each entry of the
     * supplied Map into the current variable Map.
     *
     * @param vars Contents of vars will be replaced with the content
     *      of this Map
     */
    void setVars(Map<String,Object> vars);

    /**
     * Retrives the Map of variables associated with this JexlContext.  The
     * keys of this map correspond to variable names referenced in a
     * JEXL expression.
     *
     * @return A reference to the variable Map associated with this JexlContext.
     */
    Map<String,Object> getVars();
}
