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
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
026 * and handle the case where to returned dirstyle isnt clearly defined.
027 * The matching parser will be cached.
028 * If the cached parser wont match due to the server changed the dirstyle,
029 * a new matching parser will be searched.
030 */
031public class CompositeFileEntryParser extends FTPFileEntryParserImpl
032{
033    private final FTPFileEntryParser[] ftpFileEntryParsers;
034    private FTPFileEntryParser cachedFtpFileEntryParser;
035
036    public CompositeFileEntryParser(final FTPFileEntryParser[] ftpFileEntryParsers)
037    {
038        this.cachedFtpFileEntryParser = null;
039        this.ftpFileEntryParsers = ftpFileEntryParsers;
040    }
041
042    @Override
043    public FTPFile parseFTPEntry(final String listEntry)
044    {
045        if (cachedFtpFileEntryParser != null)
046        {
047            final FTPFile matched = cachedFtpFileEntryParser.parseFTPEntry(listEntry);
048            if (matched != null)
049            {
050                return matched;
051            }
052        }
053        else
054        {
055            for (final FTPFileEntryParser ftpFileEntryParser : ftpFileEntryParsers)
056            {
057                final FTPFile matched = ftpFileEntryParser.parseFTPEntry(listEntry);
058                if (matched != null)
059                {
060                    cachedFtpFileEntryParser = ftpFileEntryParser;
061                    return matched;
062                }
063            }
064        }
065        return null;
066    }
067}