    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
    019/**
    020 * Command representing the keeping of one object present in both sequences.
    021 * <p>
    022 * When one object of the first sequence <code>equals</code> another objects in
    023 * the second sequence at the right place, the {@link EditScript edit script}
    024 * transforming the first sequence into the second sequence uses an instance of
    025 * this class to represent the keeping of this object. The objects embedded in
    026 * these type of commands always come from the first sequence.
    027 * </p>
    028 *
    029 * @see StringsComparator
    030 * @see EditScript
    031 *
    032 * @param <T> object type
    033 * @since 1.0
    034 */
    035public class KeepCommand<T> extends EditCommand<T> {
    036
    037    /**
    038     * Simple constructor. Creates a new instance of KeepCommand
    039     *
    040     * @param object  the object belonging to both sequences (the object is a
    041     *   reference to the instance in the first sequence which is known
    042     *   to be equal to an instance in the second sequence)
    043     */
    044    public KeepCommand(final T object) {
    045        super(object);
    046    }
    047
    048    /**
    049     * Accept a visitor. When a <code>KeepCommand</code> accepts a visitor, it
    050     * calls its {@link CommandVisitor#visitKeepCommand visitKeepCommand} method.
    051     *
    052     * @param visitor  the visitor to be accepted
    053     */
    054    @Override
    055    public void accept(final CommandVisitor<T> visitor) {
    056        visitor.visitKeepCommand(getObject());
    057    }
    058}