001    // Copyright 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.internal.plastic;
016    
017    import org.apache.tapestry5.plastic.FieldHandle;
018    import org.apache.tapestry5.plastic.MethodHandle;
019    import org.apache.tapestry5.plastic.MethodInvocationResult;
020    import org.apache.tapestry5.plastic.PlasticClass;
021    
022    /**
023     * The interface for a "shim" class that provides the necessary hooks needed
024     * by {@link FieldHandle} and {@link MethodHandle} implementations for a particular,
025     * instantiated {@link PlasticClass}.
026     */
027    public abstract class PlasticClassHandleShim
028    {
029        /**
030         * Gets the field at the given index.
031         * 
032         * @param instance
033         *            object to read instance field from
034         * @param fieldIndex
035         *            assigned index for the field
036         * @return the field's value
037         * @see FieldHandle#get(Object)
038         */
039        public Object get(Object instance, int fieldIndex)
040        {
041            return null;
042        }
043    
044        /**
045         * Sets the value of a field.
046         * 
047         * @param instance
048         *            object to update instance field in
049         * @param fieldIndex
050         *            assigned index for the field
051         * @param newValue
052         *            new value for field
053         * @see FieldHandle#set(Object, Object)
054         */
055        public void set(Object instance, int fieldIndex, Object newValue)
056        {
057        }
058    
059        /**
060         * Invokes a method.
061         * 
062         * @param instance
063         *            object to invoke a method upon
064         * @param methodIndex
065         *            assigned index for the method
066         * @param arguments
067         *            arguments to pass to the method
068         * @return result of invoking the method
069         */
070        public MethodInvocationResult invoke(Object instance, int methodIndex, Object[] arguments)
071        {
072            return null;
073        }
074    }