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 java.util.regex.Pattern;
021
022import org.apache.commons.net.ftp.Configurable;
023import org.apache.commons.net.ftp.FTPClientConfig;
024import org.apache.commons.net.ftp.FTPFileEntryParser;
025
026
027/**
028 * This is the default implementation of the
029 * FTPFileEntryParserFactory interface.  This is the
030 * implementation that will be used by
031 * org.apache.commons.net.ftp.FTPClient.listFiles()
032 * if no other implementation has been specified.
033 *
034 * @see org.apache.commons.net.ftp.FTPClient#listFiles
035 * @see org.apache.commons.net.ftp.FTPClient#setParserFactory
036 */
037public class DefaultFTPFileEntryParserFactory
038    implements FTPFileEntryParserFactory
039{
040
041    // Match a plain Java Identifier
042    private static final String JAVA_IDENTIFIER = "\\p{javaJavaIdentifierStart}(\\p{javaJavaIdentifierPart})*";
043    // Match a qualified name, e.g. a.b.c.Name - but don't allow the default package as that would allow "VMS"/"UNIX" etc.
044    private static final String JAVA_QUALIFIED_NAME  = "("+JAVA_IDENTIFIER+"\\.)+"+JAVA_IDENTIFIER;
045    // Create the pattern, as it will be reused many times
046    private static final Pattern JAVA_QUALIFIED_NAME_PATTERN = Pattern.compile(JAVA_QUALIFIED_NAME);
047
048    /**
049     * This default implementation of the FTPFileEntryParserFactory
050     * interface works according to the following logic:
051     * First it attempts to interpret the supplied key as a fully
052     * qualified classname (default package is not allowed) of a class implementing the
053     * FTPFileEntryParser interface.  If that succeeds, a parser
054     * object of this class is instantiated and is returned;
055     * otherwise it attempts to interpret the key as an identirier
056     * commonly used by the FTP SYST command to identify systems.
057     * <p/>
058     * If <code>key</code> is not recognized as a fully qualified
059     * classname known to the system, this method will then attempt
060     * to see whether it <b>contains</b> a string identifying one of
061     * the known parsers.  This comparison is <b>case-insensitive</b>.
062     * The intent here is where possible, to select as keys strings
063     * which are returned by the SYST command on the systems which
064     * the corresponding parser successfully parses.  This enables
065     * this factory to be used in the auto-detection system.
066     * <p/>
067     *
068     * @param key    should be a fully qualified classname corresponding to
069     *               a class implementing the FTPFileEntryParser interface<br/>
070     *               OR<br/>
071     *               a string containing (case-insensitively) one of the
072     *               following keywords:
073     *               <ul>
074     *               <li>{@link FTPClientConfig#SYST_UNIX UNIX}</li>
075     *               <li>{@link FTPClientConfig#SYST_NT WINDOWS}</li>
076     *               <li>{@link FTPClientConfig#SYST_OS2 OS/2}</li>
077     *               <li>{@link FTPClientConfig#SYST_OS400 OS/400}</li>
078     *               <li>{@link FTPClientConfig#SYST_AS400 AS/400}</li>
079     *               <li>{@link FTPClientConfig#SYST_VMS VMS}</li>
080     *               <li>{@link FTPClientConfig#SYST_MVS MVS}</li>
081     *               <li>{@link FTPClientConfig#SYST_NETWARE NETWARE}</li>
082     *               <li>{@link FTPClientConfig#SYST_L8 TYPE:L8}</li>
083     *               </ul>
084     * @return the FTPFileEntryParser corresponding to the supplied key.
085     * @throws ParserInitializationException thrown if for any reason the factory cannot resolve
086     *                   the supplied key into an FTPFileEntryParser.
087     * @see FTPFileEntryParser
088     */
089//    @Override
090    public FTPFileEntryParser createFileEntryParser(String key)
091    {
092        if (key == null) {
093            throw new ParserInitializationException("Parser key cannot be null");
094        }
095        return createFileEntryParser(key, null);
096    }
097
098    // Common method to process both key and config parameters.
099    private FTPFileEntryParser createFileEntryParser(String key, FTPClientConfig config) {
100        FTPFileEntryParser parser = null;
101
102        // Is the key a possible class name?
103        if (JAVA_QUALIFIED_NAME_PATTERN.matcher(key).matches()) {
104            try
105            {
106                Class<?> parserClass = Class.forName(key);
107                try {
108                    parser = (FTPFileEntryParser) parserClass.newInstance();
109                } catch (ClassCastException e) {
110                    throw new ParserInitializationException(parserClass.getName()
111                        + " does not implement the interface "
112                        + "org.apache.commons.net.ftp.FTPFileEntryParser.", e);
113                } catch (Exception e) {
114                    throw new ParserInitializationException("Error initializing parser", e);
115                } catch (ExceptionInInitializerError e) {
116                    throw new ParserInitializationException("Error initializing parser", e);
117                }
118            } catch (ClassNotFoundException e) {
119                // OK, assume it is an alias
120            }
121        }
122
123        if (parser == null) { // Now try for aliases
124            String ukey = key.toUpperCase(java.util.Locale.ENGLISH);
125            if (ukey.indexOf(FTPClientConfig.SYST_UNIX) >= 0)
126            {
127                parser = new UnixFTPEntryParser(config);
128            }
129            else if (ukey.indexOf(FTPClientConfig.SYST_VMS) >= 0)
130            {
131                parser = new VMSVersioningFTPEntryParser(config);
132            }
133            else if (ukey.indexOf(FTPClientConfig.SYST_NT) >= 0)
134            {
135                parser = createNTFTPEntryParser(config);
136            }
137            else if (ukey.indexOf(FTPClientConfig.SYST_OS2) >= 0)
138            {
139                parser = new OS2FTPEntryParser(config);
140            }
141            else if (ukey.indexOf(FTPClientConfig.SYST_OS400) >= 0 ||
142                    ukey.indexOf(FTPClientConfig.SYST_AS400) >= 0)
143            {
144                parser = createOS400FTPEntryParser(config);
145            }
146            else if (ukey.indexOf(FTPClientConfig.SYST_MVS) >= 0)
147            {
148                parser = new MVSFTPEntryParser(); // Does not currently support config parameter
149            }
150            else if (ukey.indexOf(FTPClientConfig.SYST_NETWARE) >= 0)
151            {
152                parser = new NetwareFTPEntryParser(config);
153            }
154            else if (ukey.indexOf(FTPClientConfig.SYST_MACOS_PETER) >= 0)
155            {
156                parser = new MacOsPeterFTPEntryParser(config);
157            }
158            else if (ukey.indexOf(FTPClientConfig.SYST_L8) >= 0)
159            {
160                // L8 normally means Unix, but move it to the end for some L8 systems that aren't.
161                // This check should be last!
162                parser = new UnixFTPEntryParser(config);
163            }
164            else
165            {
166                throw new ParserInitializationException("Unknown parser type: " + key);
167            }
168        }
169
170        if (parser instanceof Configurable) {
171            ((Configurable)parser).configure(config);
172        }
173        return parser;
174    }
175
176    /**
177     * <p>Implementation extracts a key from the supplied
178     * {@link  FTPClientConfig FTPClientConfig}
179     * parameter and creates an object implementing the
180     * interface FTPFileEntryParser and uses the supplied configuration
181     * to configure it.
182     * </p><p>
183     * Note that this method will generally not be called in scenarios
184     * that call for autodetection of parser type but rather, for situations
185     * where the user knows that the server uses a non-default configuration
186     * and knows what that configuration is.
187     * </p>
188     * @param config  A {@link  FTPClientConfig FTPClientConfig}
189     * used to configure the parser created
190     *
191     * @return the @link  FTPFileEntryParser FTPFileEntryParser} so created.
192     * @exception ParserInitializationException
193     *                   Thrown on any exception in instantiation
194     * @throws NullPointerException if {@code config} is {@code null}
195     * @since 1.4
196     */
197//    @Override
198    public FTPFileEntryParser createFileEntryParser(FTPClientConfig config)
199    throws ParserInitializationException
200    {
201        String key = config.getServerSystemKey();
202        return createFileEntryParser(key, config);
203    }
204
205
206    public FTPFileEntryParser createUnixFTPEntryParser()
207    {
208        return new UnixFTPEntryParser();
209    }
210
211    public FTPFileEntryParser createVMSVersioningFTPEntryParser()
212    {
213        return new VMSVersioningFTPEntryParser();
214    }
215
216    public FTPFileEntryParser createNetwareFTPEntryParser() {
217        return new NetwareFTPEntryParser();
218    }
219
220    public FTPFileEntryParser createNTFTPEntryParser()
221    {
222        return createNTFTPEntryParser(null);
223    }
224
225    /**
226     * Creates an NT FTP parser: if the config exists, and the system key equals
227     * {@link FTPClientConfig.SYST_NT} then a plain {@link NTFTPEntryParser} is used,
228     * otherwise a composite of {@link NTFTPEntryParser} and {@link UnixFTPEntryParser} is used.
229     * @param config the config to use, may be {@code null}
230     * @return the parser
231     */
232    private FTPFileEntryParser createNTFTPEntryParser(FTPClientConfig config)
233    {
234        if (config != null && FTPClientConfig.SYST_NT.equals(
235                config.getServerSystemKey()))
236        {
237            return new NTFTPEntryParser(config);
238        } else {
239            return new CompositeFileEntryParser(new FTPFileEntryParser[]
240                   {
241                       new NTFTPEntryParser(config),
242                       new UnixFTPEntryParser(config)
243                   });
244        }
245    }
246
247     public FTPFileEntryParser createOS2FTPEntryParser()
248    {
249        return new OS2FTPEntryParser();
250    }
251
252    public FTPFileEntryParser createOS400FTPEntryParser()
253    {
254        return createOS400FTPEntryParser(null);
255    }
256
257    /**
258     * Creates an OS400 FTP parser: if the config exists, and the system key equals
259     * {@link FTPClientConfig.SYST_OS400} then a plain {@link OS400FTPEntryParser} is used,
260     * otherwise a composite of {@link OS400FTPEntryParser} and {@link UnixFTPEntryParser} is used.
261     * @param config the config to use, may be {@code null}
262     * @return the parser
263     */
264    private FTPFileEntryParser createOS400FTPEntryParser(FTPClientConfig config)
265        {
266        if (config != null &&
267                FTPClientConfig.SYST_OS400.equals(config.getServerSystemKey()))
268        {
269            return new OS400FTPEntryParser(config);
270        } else {
271            return new CompositeFileEntryParser(new FTPFileEntryParser[]
272                {
273                    new OS400FTPEntryParser(config),
274                    new UnixFTPEntryParser(config)
275                });
276        }
277    }
278
279    public FTPFileEntryParser createMVSEntryParser()
280    {
281        return new MVSFTPEntryParser();
282    }
283
284}
285