    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 *      https://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
    018package org.apache.commons.text.diff;
    019
    020import java.util.List;
    021
    022/**
    023 * Handles synchronized replacement sequences.
    024 *
    025 * @param <T> object type
    026 * @see ReplacementsFinder
    027 * @since 1.0
    028 */
    029public interface ReplacementsHandler<T> {
    030
    031    /**
    032     * Handle two synchronized sequences.
    033     * <p>
    034     * This method is called by a {@link ReplacementsFinder ReplacementsFinder} instance when it has synchronized two sub-sequences of object arrays being
    035     * compared, and at least one of the sequences is non-empty. Since the sequences are synchronized, the objects before the two sub-sequences are equals (if
    036     * they exist). This property also holds for the objects after the two sub-sequences.
    037     * </p>
    038     * <p>
    039     * The replacement is defined as replacing the {@code from} sub-sequence into the {@code to} sub-sequence.
    040     * </p>
    041     *
    042     * @param skipped number of tokens skipped since the last call (i.e. number of tokens that were in both sequences), this number should be strictly positive
    043     *                except on the very first call where it can be zero (if the first object of the two sequences are different).
    044     * @param from    sub-sequence of objects coming from the first sequence.
    045     * @param to      sub-sequence of objects coming from the second sequence.
    046     */
    047    void handleReplacement(int skipped, List<T> from, List<T> to);
    048}