001    /*
002     * Licensed to the Apache Software Foundation (ASF) under one or more
003     * contributor license agreements.  See the NOTICE file distributed with
004     * this work for additional information regarding copyright ownership.
005     * The ASF licenses this file to You under the Apache License, Version 2.0
006     * (the "License"); you may not use this file except in compliance with
007     * the License.  You may obtain a copy of the License at
008     *
009     *      http://www.apache.org/licenses/LICENSE-2.0
010     *
011     * Unless required by applicable law or agreed to in writing, software
012     * distributed under the License is distributed on an "AS IS" BASIS,
013     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014     * See the License for the specific language governing permissions and
015     * limitations under the License.
016     */
017    package org.apache.commons.nabla.algorithmic.forward.analysis;
018    
019    import org.apache.commons.nabla.core.DifferentiationException;
020    import org.objectweb.asm.tree.AbstractInsnNode;
021    import org.objectweb.asm.tree.InsnList;
022    
023    /** Transformer for bytecode instructions.
024     * <p>Transformation is done by replacing a single instruction with
025     * a complete list.</p>
026     */
027    public interface InstructionsTransformer {
028    
029        /** Get the replacement instructions.
030         * @param original original instruction
031         * @param methodDifferentiator method differentiator driving this transformer
032         * @return replacement instructions
033         * @exception DifferentiationException if the method differentiator cannot provide
034         * a temporary variable
035         */
036        InsnList getReplacement(AbstractInsnNode original,
037                                MethodDifferentiator methodDifferentiator)
038            throws DifferentiationException;
039    
040    }