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.net.ftp.parser;
019
020import org.apache.commons.net.ftp.FTPFile;
021import org.apache.commons.net.ftp.FTPFileEntryParser;
022import org.apache.commons.net.ftp.FTPFileEntryParserImpl;
023
024/**
025 * This implementation allows to pack some FileEntryParsers together and handle the case where the returned dir style isn't clearly defined. The matching parser
026 * will be cached. If the cached parser won't match due to the server changed the dir style, a new matching parser will be searched.
027 */
028public class CompositeFileEntryParser extends FTPFileEntryParserImpl {
029    private final FTPFileEntryParser[] ftpFileEntryParsers;
030    private FTPFileEntryParser cachedFtpFileEntryParser;
031
032    /**
033     * Constructs a new instance.
034     *
035     * @param ftpFileEntryParsers An array of FTPFileEntryParser.
036     */
037    public CompositeFileEntryParser(final FTPFileEntryParser[] ftpFileEntryParsers) {
038        this.cachedFtpFileEntryParser = null;
039        this.ftpFileEntryParsers = ftpFileEntryParsers;
040    }
041
042    @Override
043    public FTPFile parseFTPEntry(final String listEntry) {
044        if (cachedFtpFileEntryParser != null) {
045            return cachedFtpFileEntryParser.parseFTPEntry(listEntry);
046        }
047        for (final FTPFileEntryParser ftpFileEntryParser : ftpFileEntryParsers) {
048            final FTPFile matched = ftpFileEntryParser.parseFTPEntry(listEntry);
049            if (matched != null) {
050                cachedFtpFileEntryParser = ftpFileEntryParser;
051                return matched;
052            }
053        }
054        return null;
055    }
056}