package org.apache.velocity.util.introspection;

/*
 * 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.
 */

/**
 *  Interface defining a 'getter'.  For uses when looking for resolution of
 *  property references
 *
 *       $foo.bar
 *
 * @author <a href="mailto:geirm@optonline.net">Geir Magnusson Jr.</a>
 * @version $Id$
 */
public interface VelPropertyGet
{
    /**
     *  invocation method - called when the 'get action' should be
     *  preformed and a value returned
     * @param o
     * @return The resulting Object.
     * @throws Exception
     */
    Object invoke(Object o) throws Exception;

    /**
     *  specifies if this VelPropertyGet is cacheable and able to be
     *  reused for this class of object it was returned for
     *
     *  @return true if can be reused for this class, false if not
     */
    boolean isCacheable();

    /**
     *  returns the method name used to return this 'property'
     * @return The method name used to return this 'property'
     */
    String getMethodName();
}
