001    // Copyright 2004, 2005 The Apache Software Foundation
002    //
003    // Licensed under the Apache License, Version 2.0 (the "License");
004    // you may not use this file except in compliance with the License.
005    // You may obtain a copy of the License at
006    //
007    //     http://www.apache.org/licenses/LICENSE-2.0
008    //
009    // Unless required by applicable law or agreed to in writing, software
010    // distributed under the License is distributed on an "AS IS" BASIS,
011    // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
012    // See the License for the specific language governing permissions and
013    // limitations under the License.
014    
015    package org.apache.tapestry.engine;
016    
017    import org.apache.tapestry.spec.IComponentSpecification;
018    
019    /**
020     * A provider of enhanced classes, classes with new methods and new attributes, and possibly,
021     * implementing new Java interfaces. The primary use of class enhancement is to automate the
022     * creation of transient and persistant properties.
023     * <p>
024     * Implementations of this interface must be threadsafe.
025     * 
026     * @author Howard Lewis Ship
027     * @since 3.0
028     * @deprecated To be removed in 4.1
029     * @see org.apache.tapestry.services.ComponentConstructorFactory
030     */
031    
032    public interface IComponentClassEnhancer
033    {
034        /**
035         * Used to access the class for a given component (or page). Returns the specified class, or an
036         * enhanced version of the class if the component requires enhancement.
037         * 
038         * @param specification
039         *            the specification for the component
040         * @param className
041         *            the name of base class to enhance, as extracted from the specification (or
042         *            possibly, from a default).
043         * @throws org.apache.tapestry.ApplicationRuntimeException
044         *             if the class does not exist, is invalid, or may not be enhanced.
045         */
046    
047        public Class getEnhancedClass(IComponentSpecification specification, String className);
048    }