/*
 * Copyright (c) 1997, 2020 Oracle and/or its affiliates and others.
 * All rights reserved.
 * Copyright 2004 The Apache Software Foundation
 *
 * Licensed 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 jakarta.servlet.jsp.el;

/**
 * <p>
 * This class is used to customize the way an ExpressionEvaluator resolves variable references at evaluation time. For
 * example, instances of this class can implement their own variable lookup mechanisms, or introduce the notion of
 * "implicit variables" which override any other variables. An instance of this class should be passed when evaluating
 * an expression.
 * </p>
 *
 * <p>
 * An instance of this class includes the context against which resolution will happen
 * </p>
 *
 * @deprecated As of JSP 2.1, replaced by {@link jakarta.el.ELResolver}
 * @since JSP 2.0
 */
@Deprecated
public interface VariableResolver {

    /**
     * Resolves the specified variable. Returns null if the variable is not found.
     * 
     * @param pName the name of the variable to resolve
     * @return the result of the variable resolution
     *
     * @throws ELException if a failure occurred while trying to resolve the given variable
     */
    public Object resolveVariable(String pName) throws ELException;
}
