    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 java.util.Locale;
    021import java.util.regex.Pattern;
    022
    023import org.apache.commons.net.ftp.Configurable;
    024import org.apache.commons.net.ftp.FTPClientConfig;
    025import org.apache.commons.net.ftp.FTPFileEntryParser;
    026
    027/**
    028 * This is the default implementation of the FTPFileEntryParserFactory interface. This is the implementation that will be used by
    029 * org.apache.commons.net.ftp.FTPClient.listFiles() if no other implementation has been specified.
    030 *
    031 * @see org.apache.commons.net.ftp.FTPClient#listFiles
    032 * @see org.apache.commons.net.ftp.FTPClient#setParserFactory
    033 */
    034public class DefaultFTPFileEntryParserFactory implements FTPFileEntryParserFactory {
    035
    036    /**
    037     * Match a plain Java Identifier
    038     */
    039    private static final String JAVA_IDENTIFIER = "\\p{javaJavaIdentifierStart}(\\p{javaJavaIdentifierPart})*";
    040
    041    /**
    042     * Match a qualified name, e.g. a.b.c.Name - but don't allow the default package as that would allow "VMS"/"UNIX" etc.
    043     */
    044    private static final String JAVA_QUALIFIED_NAME = "(" + JAVA_IDENTIFIER + "\\.)+" + JAVA_IDENTIFIER;
    045
    046    /**
    047     * Create the pattern, as it will be reused many times
    048     */
    049    private static final Pattern JAVA_QUALIFIED_NAME_PATTERN = Pattern.compile(JAVA_QUALIFIED_NAME);
    050
    051    /**
    052     * Constructs a new instance.
    053     */
    054    public DefaultFTPFileEntryParserFactory() {
    055        // empty
    056    }
    057
    058    /**
    059     * Implementation extracts a key from the supplied {@link FTPClientConfig FTPClientConfig} parameter and creates an object implementing the interface
    060     * FTPFileEntryParser and uses the supplied configuration to configure it.
    061     * <p>
    062     * Note that this method will generally not be called in scenarios that call for autodetection of parser type but rather, for situations where the user
    063     * knows that the server uses a non-default configuration and knows what that configuration is.
    064     * </p>
    065     *
    066     * @param config A {@link FTPClientConfig FTPClientConfig} used to configure the parser created
    067     * @return the {@link FTPFileEntryParser} so created.
    068     * @throws ParserInitializationException Thrown on any exception in instantiation
    069     * @throws NullPointerException          if {@code config} is {@code null}
    070     * @since 1.4
    071     */
    072    @Override
    073    public FTPFileEntryParser createFileEntryParser(final FTPClientConfig config) throws ParserInitializationException {
    074        return createFileEntryParser(config.getServerSystemKey(), config);
    075    }
    076
    077    /**
    078     * This default implementation of the FTPFileEntryParserFactory interface works according to the following logic: First it attempts to interpret the
    079     * supplied key as a fully qualified class name (default package is not allowed) of a class implementing the FTPFileEntryParser interface. If that succeeds,
    080     * a parser object of this class is instantiated and is returned; otherwise it attempts to interpret the key as an identifier commonly used by the FTP SYST
    081     * command to identify systems.
    082     * <p>
    083     * If {@code key} is not recognized as a fully qualified class name known to the system, this method will then attempt to see whether it
    084     * <strong>contains</strong> a string identifying one of the known parsers. This comparison is <strong>case-insensitive</strong>. The intent here is where
    085     * possible, to select as keys strings which are returned by the SYST command on the systems which the corresponding parser successfully parses. This
    086     * enables this factory to be used in the auto-detection system.
    087     * </p>
    088     *
    089     * @param key should be a fully qualified class name corresponding to a class implementing the FTPFileEntryParser interface<br>
    090     *            OR<br>
    091     *            a string containing (case-insensitively) one of the following keywords:
    092     *            <ul>
    093     *            <li>{@link FTPClientConfig#SYST_UNIX UNIX}</li>
    094     *            <li>{@link FTPClientConfig#SYST_NT WINDOWS}</li>
    095     *            <li>{@link FTPClientConfig#SYST_OS2 OS/2}</li>
    096     *            <li>{@link FTPClientConfig#SYST_OS400 OS/400}</li>
    097     *            <li>{@link FTPClientConfig#SYST_AS400 AS/400}</li>
    098     *            <li>{@link FTPClientConfig#SYST_VMS VMS}</li>
    099     *            <li>{@link FTPClientConfig#SYST_MVS MVS}</li>
    100     *            <li>{@link FTPClientConfig#SYST_NETWARE NETWARE}</li>
    101     *            <li>{@link FTPClientConfig#SYST_L8 TYPE:L8}</li>
    102     *            </ul>
    103     * @return the FTPFileEntryParser corresponding to the supplied key.
    104     * @throws ParserInitializationException thrown if for any reason the factory cannot resolve the supplied key into an FTPFileEntryParser.
    105     * @see FTPFileEntryParser
    106     */
    107    @Override
    108    public FTPFileEntryParser createFileEntryParser(final String key) {
    109        if (key == null) {
    110            throw new ParserInitializationException("Parser key cannot be null");
    111        }
    112        return createFileEntryParser(key, null);
    113    }
    114
    115    // Common method to process both key and config parameters.
    116    private FTPFileEntryParser createFileEntryParser(final String key, final FTPClientConfig config) {
    117        FTPFileEntryParser parser = null;
    118        // Is the key a possible class name?
    119        if (JAVA_QUALIFIED_NAME_PATTERN.matcher(key).matches()) {
    120            try {
    121                final Class<?> parserClass = Class.forName(key);
    122                try {
    123                    parser = (FTPFileEntryParser) parserClass.getConstructor().newInstance();
    124                } catch (final ClassCastException e) {
    125                    throw new ParserInitializationException(
    126                            parserClass.getName() + " does not implement the interface " + FTPFileEntryParser.class.getCanonicalName(), e);
    127                } catch (final Exception | LinkageError e) {
    128                    throw new ParserInitializationException("Error initializing parser", e);
    129                }
    130            } catch (final ClassNotFoundException e) {
    131                // OK, assume it is an alias
    132            }
    133        }
    134        if (parser == null) { // Now try for aliases
    135            final String upperKey = key.toUpperCase(Locale.ENGLISH);
    136            if (upperKey.contains(FTPClientConfig.SYST_UNIX_TRIM_LEADING)) {
    137                parser = new UnixFTPEntryParser(config, true);
    138                // must check this after SYST_UNIX_TRIM_LEADING as it is a substring of it
    139            } else if (upperKey.contains(FTPClientConfig.SYST_UNIX)) {
    140                parser = new UnixFTPEntryParser(config, false);
    141            } else if (upperKey.contains(FTPClientConfig.SYST_VMS)) {
    142                parser = new VMSVersioningFTPEntryParser(config);
    143            } else if (upperKey.contains(FTPClientConfig.SYST_NT)) {
    144                parser = createNTFTPEntryParser(config);
    145            } else if (upperKey.contains(FTPClientConfig.SYST_OS2)) {
    146                parser = new OS2FTPEntryParser(config);
    147            } else if (upperKey.contains(FTPClientConfig.SYST_OS400) || upperKey.contains(FTPClientConfig.SYST_AS400)) {
    148                parser = createOS400FTPEntryParser(config);
    149            } else if (upperKey.contains(FTPClientConfig.SYST_MVS)) {
    150                parser = new MVSFTPEntryParser(); // Does not currently support config parameter
    151            } else if (upperKey.contains(FTPClientConfig.SYST_NETWARE)) {
    152                parser = new NetwareFTPEntryParser(config);
    153            } else if (upperKey.contains(FTPClientConfig.SYST_MACOS_PETER)) {
    154                parser = new MacOsPeterFTPEntryParser(config);
    155            } else if (upperKey.contains(FTPClientConfig.SYST_L8)) {
    156                // L8 normally means Unix, but move it to the end for some L8 systems that aren't.
    157                // This check should be last!
    158                parser = new UnixFTPEntryParser(config);
    159            } else {
    160                throw new ParserInitializationException("Unknown parser type: " + key);
    161            }
    162        }
    163        if (parser instanceof Configurable) {
    164            ((Configurable) parser).configure(config);
    165        }
    166        return parser;
    167    }
    168
    169    /**
    170     * Creates a new MVSFTPEntryParser.
    171     *
    172     * @return  a new MVSFTPEntryParser.
    173     */
    174    public FTPFileEntryParser createMVSEntryParser() {
    175        return new MVSFTPEntryParser();
    176    }
    177
    178    /**
    179     * Creates a new NetwareFTPEntryParser.
    180     *
    181     * @return  a new NetwareFTPEntryParser.
    182     */
    183    public FTPFileEntryParser createNetwareFTPEntryParser() {
    184        return new NetwareFTPEntryParser();
    185    }
    186
    187    /**
    188     * Creates a new FTPFileEntryParser.
    189     *
    190     * @return  a new FTPFileEntryParser.
    191     */
    192    public FTPFileEntryParser createNTFTPEntryParser() {
    193        return createNTFTPEntryParser(null);
    194    }
    195
    196    /**
    197     * Creates an NT FTP parser: if the config exists, and the system key equals {@link FTPClientConfig#SYST_NT} then a plain {@link NTFTPEntryParser} is used,
    198     * otherwise a composite of {@link NTFTPEntryParser} and {@link UnixFTPEntryParser} is used.
    199     *
    200     * @param config the config to use, may be {@code null}
    201     * @return the parser
    202     */
    203    private FTPFileEntryParser createNTFTPEntryParser(final FTPClientConfig config) {
    204        if (config != null && FTPClientConfig.SYST_NT.equals(config.getServerSystemKey())) {
    205            return new NTFTPEntryParser(config);
    206        }
    207        // clone the config as it may be changed by the parsers (NET-602)
    208        final FTPClientConfig config2 = config != null ? new FTPClientConfig(config) : null;
    209        return new CompositeFileEntryParser(new FTPFileEntryParser[] { new NTFTPEntryParser(config),
    210                new UnixFTPEntryParser(config2, config2 != null && FTPClientConfig.SYST_UNIX_TRIM_LEADING.equals(config2.getServerSystemKey()))});
    211    }
    212
    213    /**
    214     * Creates a new OS2FTPEntryParser.
    215     *
    216     * @return  a new OS2FTPEntryParser.
    217     */
    218    public FTPFileEntryParser createOS2FTPEntryParser() {
    219        return new OS2FTPEntryParser();
    220    }
    221
    222    /**
    223     * Creates a new FTPFileEntryParser.
    224     *
    225     * @return  a new FTPFileEntryParser.
    226     */
    227    public FTPFileEntryParser createOS400FTPEntryParser() {
    228        return createOS400FTPEntryParser(null);
    229    }
    230
    231    /**
    232     * Creates an OS400 FTP parser: if the config exists, and the system key equals {@link FTPClientConfig#SYST_OS400} then a plain {@link OS400FTPEntryParser}
    233     * is used, otherwise a composite of {@link OS400FTPEntryParser} and {@link UnixFTPEntryParser} is used.
    234     *
    235     * @param config the config to use, may be {@code null}
    236     * @return the parser
    237     */
    238    private FTPFileEntryParser createOS400FTPEntryParser(final FTPClientConfig config) {
    239        if (config != null && FTPClientConfig.SYST_OS400.equals(config.getServerSystemKey())) {
    240            return new OS400FTPEntryParser(config);
    241        }
    242        // clone the config as it may be changed by the parsers (NET-602)
    243        final FTPClientConfig config2 = config != null ? new FTPClientConfig(config) : null;
    244        return new CompositeFileEntryParser(new FTPFileEntryParser[] { new OS400FTPEntryParser(config),
    245                new UnixFTPEntryParser(config2, config2 != null && FTPClientConfig.SYST_UNIX_TRIM_LEADING.equals(config2.getServerSystemKey()))});
    246    }
    247
    248    /**
    249     * Creates a new UnixFTPEntryParser.
    250     *
    251     * @return  a new UnixFTPEntryParser.
    252     */
    253    public FTPFileEntryParser createUnixFTPEntryParser() {
    254        return new UnixFTPEntryParser();
    255    }
    256
    257    /**
    258     * Creates a new VMSVersioningFTPEntryParser.
    259     *
    260     * @return  a new VMSVersioningFTPEntryParser.
    261     */
    262    public FTPFileEntryParser createVMSVersioningFTPEntryParser() {
    263        return new VMSVersioningFTPEntryParser();
    264    }
    265
    266}