001    // Copyright 2010, 2011 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.tapestry5.services;
016    
017    import org.apache.tapestry5.ComponentResources;
018    
019    /**
020     * An object used to provide a value of a specific type to a component (represented by an
021     * instance of {@link ComponentResources}). The provider will create and return the value
022     * (some providers may be smart enough to cache a value, but should be implemented in
023     * a thread-safe manner). Often the provider is an inner class of a {@link ComponentClassTransformWorker}.
024     * 
025     * @param <T>
026     *            type of object provided
027     * @since 5.2.0
028     * @deprecated Deprecated in 5.3, using Plastic equivalents
029     * @see org.apache.tapestry5.plastic.PlasticField
030     * @see org.apache.tapestry5.plastic.ComputedValue
031     */
032    @SuppressWarnings("deprecation")
033    public interface ComponentValueProvider<T>
034    {
035        /**
036         * Provide the object for the indicated component.
037         * 
038         * @param resources
039         *            Identifies the component
040         * @return the object
041         */
042        T get(ComponentResources resources);
043    }