package org.codehaus.plexus.component.configurator.expression;

/*
 * Copyright 2001-2006 Codehaus 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.
 */

/**
 * Evaluate an expression.
 *
 * @author <a href="mailto:brett@codehaus.org">Brett Porter</a>
 * @version $Id: TypeAwareExpressionEvaluator.java 8347 2009-08-20 17:37:19Z bentmann $
 */
public interface TypeAwareExpressionEvaluator
    extends ExpressionEvaluator
{

    /**
     * Evaluate an expression. The optional type provided to this method is a hint (not a requirement) for the evaluator
     * to resolve the expression to a compatible value. The evaluator is not expected to perform any conversion but
     * rather filter out incompatible values from its result.
     * 
     * @param expression the expression
     * @param type The expected type of expression result, may be {@code null}.
     * @return the value of the expression
     */
    Object evaluate( String expression, Class<?> type )
        throws ExpressionEvaluationException;

}
