    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 */
    017package org.apache.commons.text.diff;
    018
    019import java.util.List;
    020
    021/**
    022 * This interface is devoted to handle synchronized replacement sequences.
    023 *
    024 * @param <T> object type
    025 * @see ReplacementsFinder
    026 * @since 1.0
    027 */
    028public interface ReplacementsHandler<T> {
    029
    030    /**
    031     * Handle two synchronized sequences.
    032     * <p>
    033     * This method is called by a {@link ReplacementsFinder ReplacementsFinder}
    034     * instance when it has synchronized two sub-sequences of object arrays
    035     * being compared, and at least one of the sequences is non-empty. Since the
    036     * sequences are synchronized, the objects before the two sub-sequences are
    037     * equals (if they exist). This property also holds for the objects after
    038     * the two sub-sequences.
    039     * </p>
    040     * <p>
    041     * The replacement is defined as replacing the {@code from}
    042     * sub-sequence into the {@code to} sub-sequence.
    043     * </p>
    044     *
    045     * @param skipped  number of tokens skipped since the last call (i.e. number of
    046     *   tokens that were in both sequences), this number should be strictly positive
    047     *   except on the very first call where it can be zero (if the first object of
    048     *   the two sequences are different)
    049     * @param from  sub-sequence of objects coming from the first sequence
    050     * @param to  sub-sequence of objects coming from the second sequence
    051     */
    052    void handleReplacement(int skipped, List<T> from, List<T> to);
    053
    054}