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1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one or more
3    * contributor license agreements.  See the NOTICE file distributed with
4    * this work for additional information regarding copyright ownership.
5    * The ASF licenses this file to You under the Apache License, Version 2.0
6    * (the "License"); you may not use this file except in compliance with
7    * the License.  You may obtain a copy of the License at
8    *
9    *      http://www.apache.org/licenses/LICENSE-2.0
10   *
11   * Unless required by applicable law or agreed to in writing, software
12   * distributed under the License is distributed on an "AS IS" BASIS,
13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14   * See the License for the specific language governing permissions and
15   * limitations under the License.
16   */
17  
18  package org.apache.commons.net.ftp;
19  
20  import java.text.DateFormatSymbols;
21  import java.util.Collection;
22  import java.util.Locale;
23  import java.util.Map;
24  import java.util.StringTokenizer;
25  import java.util.TreeMap;
26  
27  /**
28   * <p>
29   * This class implements an alternate means of configuring the
30   * {@link  org.apache.commons.net.ftp.FTPClient  FTPClient} object and
31   * also subordinate objects which it uses.  Any class implementing the
32   * {@link  org.apache.commons.net.ftp.Configurable  Configurable }
33   * interface can be configured by this object.
34   * </p><p>
35   * In particular this class was designed primarily to support configuration
36   * of FTP servers which express file timestamps in formats and languages
37   * other than those for the US locale, which although it is the most common
38   * is not universal.  Unfortunately, nothing in the FTP spec allows this to
39   * be determined in an automated way, so manual configuration such as this
40   * is necessary.
41   * </p><p>
42   * This functionality was designed to allow existing clients to work exactly
43   * as before without requiring use of this component.  This component should
44   * only need to be explicitly invoked by the user of this package for problem
45   * cases that previous implementations could not solve.
46   * </p>
47   * <h3>Examples of use of FTPClientConfig</h3>
48   * Use cases:
49   * You are trying to access a server that
50   * <ul>
51   * <li>lists files with timestamps that use month names in languages other
52   * than English</li>
53   * <li>lists files with timestamps that use date formats other
54   * than the American English "standard" <code>MM dd yyyy</code></li>
55   * <li>is in different timezone and you need accurate timestamps for
56   * dependency checking as in Ant</li>
57   * </ul>
58   * <p>
59   * Unpaged (whole list) access on a UNIX server that uses French month names
60   * but uses the "standard" <code>MMM d yyyy</code> date formatting
61   * <pre>
62   *    FTPClient f=FTPClient();
63   *    FTPClientConfig conf = new FTPClientConfig(FTPClientConfig.SYST_UNIX);
64   *    conf.setServerLanguageCode("fr");
65   *    f.configure(conf);
66   *    f.connect(server);
67   *    f.login(username, password);
68   *    FTPFile[] files = listFiles(directory);
69   * </pre>
70   * </p>
71   * <p>
72   * Paged access on a UNIX server that uses Danish month names
73   * and "European" date formatting in Denmark's time zone, when you
74   * are in some other time zone.
75   * <pre>
76   *    FTPClient f=FTPClient();
77   *    FTPClientConfig conf = new FTPClientConfig(FTPClientConfig.SYST_UNIX);
78   *    conf.setServerLanguageCode("da");
79   *    conf.setDefaultDateFormat("d MMM yyyy");
80   *    conf.setRecentDateFormat("d MMM HH:mm");
81   *    conf.setTimeZoneId("Europe/Copenhagen");
82   *    f.configure(conf);
83   *    f.connect(server);
84   *    f.login(username, password);
85   *    FTPListParseEngine engine =
86   *       f.initiateListParsing("com.whatever.YourOwnParser", directory);
87   *
88   *    while (engine.hasNext()) {
89   *       FTPFile[] files = engine.getNext(25);  // "page size" you want
90   *       //do whatever you want with these files, display them, etc.
91   *       //expensive FTPFile objects not created until needed.
92   *    }
93   * </pre>
94   * </p>
95   * <p>
96   * Unpaged (whole list) access on a VMS server that uses month names
97   * in a language not {@link #getSupportedLanguageCodes() supported} by the system.
98   * but uses the "standard" <code>MMM d yyyy</code> date formatting
99   * <pre>
100  *    FTPClient f=FTPClient();
101  *    FTPClientConfig conf = new FTPClientConfig(FTPClientConfig.SYST_VMS);
102  *    conf.setShortMonthNames(
103  *        "jan|feb|mar|apr|ma\u00ED|j\u00FAn|j\u00FAl|\u00e1g\u00FA|sep|okt|n\u00F3v|des");
104  *    f.configure(conf);
105  *    f.connect(server);
106  *    f.login(username, password);
107  *    FTPFile[] files = listFiles(directory);
108  * </pre>
109  * </p>
110  * <p>
111  * Unpaged (whole list) access on a Windows-NT server in a different time zone.
112  * (Note, since the NT Format uses numeric date formatting, language issues
113  * are irrelevant here).
114  * <pre>
115  *    FTPClient f=FTPClient();
116  *    FTPClientConfig conf = new FTPClientConfig(FTPClientConfig.SYST_NT);
117  *    conf.setTimeZoneId("America/Denver");
118  *    f.configure(conf);
119  *    f.connect(server);
120  *    f.login(username, password);
121  *    FTPFile[] files = listFiles(directory);
122  * </pre>
123  * </p>
124  * Unpaged (whole list) access on a Windows-NT server in a different time zone
125  * but which has been configured to use a unix-style listing format.
126  * <pre>
127  *    FTPClient f=FTPClient();
128  *    FTPClientConfig conf = new FTPClientConfig(FTPClientConfig.SYST_UNIX);
129  *    conf.setTimeZoneId("America/Denver");
130  *    f.configure(conf);
131  *    f.connect(server);
132  *    f.login(username, password);
133  *    FTPFile[] files = listFiles(directory);
134  * </pre>
135  *
136  * @since 1.4
137  * @see org.apache.commons.net.ftp.Configurable
138  * @see org.apache.commons.net.ftp.FTPClient
139  * @see org.apache.commons.net.ftp.parser.FTPTimestampParserImpl#configure(FTPClientConfig)
140  * @see org.apache.commons.net.ftp.parser.ConfigurableFTPFileEntryParserImpl
141  */
142 public class FTPClientConfig
143 {
144 
145     /**
146      * Identifier by which a unix-based ftp server is known throughout
147      * the commons-net ftp system.
148      */
149     public static final String SYST_UNIX  = "UNIX";
150 
151     /**
152      * Identifier by which a vms-based ftp server is known throughout
153      * the commons-net ftp system.
154      */
155     public static final String SYST_VMS   = "VMS";
156 
157     /**
158      * Identifier by which a WindowsNT-based ftp server is known throughout
159      * the commons-net ftp system.
160      */
161     public static final String SYST_NT    = "WINDOWS";
162 
163     /**
164      * Identifier by which an OS/2-based ftp server is known throughout
165      * the commons-net ftp system.
166      */
167     public static final String SYST_OS2   = "OS/2";
168 
169     /**
170      * Identifier by which an OS/400-based ftp server is known throughout
171      * the commons-net ftp system.
172      */
173     public static final String SYST_OS400 = "OS/400";
174 
175     /**
176      * Identifier by which an AS/400-based ftp server is known throughout
177      * the commons-net ftp system.
178      */
179     public static final String SYST_AS400 = "AS/400";
180 
181     /**
182      * Identifier by which an MVS-based ftp server is known throughout
183      * the commons-net ftp system.
184      */
185     public static final String SYST_MVS = "MVS";
186 
187     /**
188      * Some servers return an "UNKNOWN Type: L8" message
189      * in response to the SYST command. We set these to be a Unix-type system.
190      * This may happen if the ftpd in question was compiled without system
191      * information.
192      *
193      * NET-230 - Updated to be UPPERCASE so that the check done in
194      * createFileEntryParser will succeed.
195      *
196      * @since 1.5
197      */
198     public static final String SYST_L8 = "TYPE: L8";
199 
200     /**
201      * Identifier by which an Netware-based ftp server is known throughout
202      * the commons-net ftp system.
203      *
204      * @since 1.5
205      */
206     public static final String SYST_NETWARE = "NETWARE";
207 
208     /**
209      * Identifier by which a Mac pre OS-X -based ftp server is known throughout
210      * the commons-net ftp system.
211      *
212      * @since 3.1
213      */
214     // Full string is "MACOS Peter's Server"; the substring below should be enough
215     public static final String SYST_MACOS_PETER  = "MACOS PETER"; // NET-436
216 
217     private final String serverSystemKey;
218     private String defaultDateFormatStr = null;
219     private String recentDateFormatStr = null;
220     private boolean lenientFutureDates = true; // NET-407
221     private String serverLanguageCode = null;
222     private String shortMonthNames = null;
223     private String serverTimeZoneId = null;
224 
225 
226     /**
227      * The main constructor for an FTPClientConfig object
228      * @param systemKey key representing system type of the  server being
229      * connected to. See {@link #getServerSystemKey() serverSystemKey}
230      */
231     public FTPClientConfig(String systemKey) {
232         this.serverSystemKey = systemKey;
233     }
234 
235     /**
236      * Convenience constructor mainly for use in testing.
237      * Constructs a UNIX configuration.
238      */
239     public FTPClientConfig() {
240         this(SYST_UNIX);
241     }
242 
243     /**
244      * Constructor which allows setting of all member fields
245      * @param systemKey key representing system type of the  server being
246      * connected to. See
247      *  {@link #getServerSystemKey() serverSystemKey}
248      * @param defaultDateFormatStr See
249      *  {@link  #setDefaultDateFormatStr(String)  defaultDateFormatStr}
250      * @param recentDateFormatStr See
251      *  {@link  #setRecentDateFormatStr(String)  recentDateFormatStr}
252      * @param serverLanguageCode See
253      *  {@link  #setServerLanguageCode(String)  serverLanguageCode}
254      * @param shortMonthNames See
255      *  {@link  #setShortMonthNames(String)  shortMonthNames}
256      * @param serverTimeZoneId See
257      *  {@link  #setServerTimeZoneId(String)  serverTimeZoneId}
258      */
259     public FTPClientConfig(String systemKey,
260                            String defaultDateFormatStr,
261                            String recentDateFormatStr,
262                            String serverLanguageCode,
263                            String shortMonthNames,
264                            String serverTimeZoneId)
265     {
266         this(systemKey);
267         this.defaultDateFormatStr = defaultDateFormatStr;
268         this.recentDateFormatStr = recentDateFormatStr;
269         this.serverLanguageCode = serverLanguageCode;
270         this.shortMonthNames = shortMonthNames;
271         this.serverTimeZoneId = serverTimeZoneId;
272     }
273 
274     private static final Map<String, Object> LANGUAGE_CODE_MAP = new TreeMap<String, Object>();
275     static {
276 
277         // if there are other commonly used month name encodings which
278         // correspond to particular locales, please add them here.
279 
280 
281 
282         // many locales code short names for months as all three letters
283         // these we handle simply.
284         LANGUAGE_CODE_MAP.put("en", Locale.ENGLISH);
285         LANGUAGE_CODE_MAP.put("de",Locale.GERMAN);
286         LANGUAGE_CODE_MAP.put("it",Locale.ITALIAN);
287         LANGUAGE_CODE_MAP.put("es", new Locale("es", "", "")); // spanish
288         LANGUAGE_CODE_MAP.put("pt", new Locale("pt", "", "")); // portuguese
289         LANGUAGE_CODE_MAP.put("da", new Locale("da", "", "")); // danish
290         LANGUAGE_CODE_MAP.put("sv", new Locale("sv", "", "")); // swedish
291         LANGUAGE_CODE_MAP.put("no", new Locale("no", "", "")); // norwegian
292         LANGUAGE_CODE_MAP.put("nl", new Locale("nl", "", "")); // dutch
293         LANGUAGE_CODE_MAP.put("ro", new Locale("ro", "", "")); // romanian
294         LANGUAGE_CODE_MAP.put("sq", new Locale("sq", "", "")); // albanian
295         LANGUAGE_CODE_MAP.put("sh", new Locale("sh", "", "")); // serbo-croatian
296         LANGUAGE_CODE_MAP.put("sk", new Locale("sk", "", "")); // slovak
297         LANGUAGE_CODE_MAP.put("sl", new Locale("sl", "", "")); // slovenian
298 
299 
300         // some don't
301         LANGUAGE_CODE_MAP.put("fr",
302                 "jan|f\u00e9v|mar|avr|mai|jun|jui|ao\u00fb|sep|oct|nov|d\u00e9c");  //french
303 
304     }
305 
306     /**
307      * Getter for the serverSystemKey property.  This property
308      * specifies the general type of server to which the client connects.
309      * Should be either one of the <code>FTPClientConfig.SYST_*</code> codes
310      * or else the fully qualified class name of a parser implementing both
311      * the <code>FTPFileEntryParser</code> and <code>Configurable</code>
312      * interfaces.
313      * @return Returns the serverSystemKey property.
314      */
315     public String getServerSystemKey() {
316         return serverSystemKey;
317     }
318 
319     /**
320      * getter for the {@link  #setDefaultDateFormatStr(String)  defaultDateFormatStr}
321      * property.
322      * @return Returns the defaultDateFormatStr property.
323      */
324     public String getDefaultDateFormatStr() {
325         return defaultDateFormatStr;
326     }
327 
328     /**
329      * getter for the {@link  #setRecentDateFormatStr(String)  recentDateFormatStr} property.
330      * @return Returns the recentDateFormatStr property.
331      */
332 
333     public String getRecentDateFormatStr() {
334         return recentDateFormatStr;
335     }
336 
337     /**
338      * getter for the {@link  #setServerTimeZoneId(String)  serverTimeZoneId} property.
339      * @return Returns the serverTimeZoneId property.
340      */
341     public String getServerTimeZoneId() {
342         return serverTimeZoneId;
343     }
344 
345     /**
346      * <p>
347      * getter for the {@link  #setShortMonthNames(String)  shortMonthNames}
348      * property.
349      * </p>
350      * @return Returns the shortMonthNames.
351      */
352     public String getShortMonthNames() {
353         return shortMonthNames;
354     }
355 
356     /**
357      * <p>
358      * getter for the {@link  #setServerLanguageCode(String)  serverLanguageCode} property.
359      * </p>
360      * @return Returns the serverLanguageCode property.
361      */
362     public String getServerLanguageCode() {
363         return serverLanguageCode;
364     }
365 
366     /**
367      * <p>
368      * getter for the {@link  #setLenientFutureDates(boolean)  lenientFutureDates} property.
369      * </p>
370      * @return Returns the lenientFutureDates.
371      * @since 1.5
372      */
373     public boolean isLenientFutureDates() {
374         return lenientFutureDates;
375     }
376     /**
377      * <p>
378      * setter for the defaultDateFormatStr property.  This property
379      * specifies the main date format that will be used by a parser configured
380      * by this configuration to parse file timestamps.  If this is not
381      * specified, such a parser will use as a default value, the most commonly
382      * used format which will be in as used in <code>en_US</code> locales.
383      * </p><p>
384      * This should be in the format described for
385      * <code>java.text.SimpleDateFormat</code>.
386      * property.
387      * </p>
388      * @param defaultDateFormatStr The defaultDateFormatStr to set.
389      */
390     public void setDefaultDateFormatStr(String defaultDateFormatStr) {
391         this.defaultDateFormatStr = defaultDateFormatStr;
392     }
393 
394     /**
395      * <p>
396      * setter for the recentDateFormatStr property.  This property
397      * specifies a secondary date format that will be used by a parser
398      * configured by this configuration to parse file timestamps, typically
399      * those less than a year old.  If this is  not specified, such a parser
400      * will not attempt to parse using an alternate format.
401      * </p>
402      * <p>
403      * This is used primarily in unix-based systems.
404      * </p>
405      * <p>
406      * This should be in the format described for
407      * <code>java.text.SimpleDateFormat</code>.
408      * </p>
409      * @param recentDateFormatStr The recentDateFormatStr to set.
410      */
411     public void setRecentDateFormatStr(String recentDateFormatStr) {
412         this.recentDateFormatStr = recentDateFormatStr;
413     }
414 
415     /**
416      * <p>
417      * setter for the lenientFutureDates property.  This boolean property
418      * (default: false) only has meaning when a
419      * {@link  #setRecentDateFormatStr(String)  recentDateFormatStr} property
420      * has been set.  In that case, if this property is set true, then the
421      * parser, when it encounters a listing parseable with the recent date
422      * format, will only consider a date to belong to the previous year if
423      * it is more than one day in the future.  This will allow all
424      * out-of-synch situations (whether based on "slop" - i.e. servers simply
425      * out of synch with one another or because of time zone differences -
426      * but in the latter case it is highly recommended to use the
427      * {@link  #setServerTimeZoneId(String)  serverTimeZoneId} property
428      * instead) to resolve correctly.
429      * </p><p>
430      * This is used primarily in unix-based systems.
431      * </p>
432      * @param lenientFutureDates set true to compensate for out-of-synch
433      * conditions.
434      */
435     public void setLenientFutureDates(boolean lenientFutureDates) {
436         this.lenientFutureDates = lenientFutureDates;
437     }
438     /**
439      * <p>
440      * setter for the serverTimeZoneId property.  This property
441      * allows a time zone to be specified corresponding to that known to be
442      * used by an FTP server in file listings.  This might be particularly
443      * useful to clients such as Ant that try to use these timestamps for
444      * dependency checking.
445      * </p><p>
446      * This should be one of the identifiers used by
447      * <code>java.util.TimeZone</code> to refer to time zones, for example,
448      * <code>America/Chicago</code> or <code>Asia/Rangoon</code>.
449      * </p>
450      * @param serverTimeZoneId The serverTimeZoneId to set.
451      */
452     public void setServerTimeZoneId(String serverTimeZoneId) {
453         this.serverTimeZoneId = serverTimeZoneId;
454     }
455 
456     /**
457      * <p>
458      * setter for the shortMonthNames property.
459      * This property allows the user to specify a set of month names
460      * used by the server that is different from those that may be
461      * specified using the {@link  #setServerLanguageCode(String)  serverLanguageCode}
462      * property.
463      * </p><p>
464      * This should be a string containing twelve strings each composed of
465      * three characters, delimited by pipe (|) characters.  Currently,
466      * only 8-bit ASCII characters are known to be supported.  For example,
467      * a set of month names used by a hypothetical Icelandic FTP server might
468      * conceivably be specified as
469      * <code>"jan|feb|mar|apr|ma&#xED;|j&#xFA;n|j&#xFA;l|&#xE1;g&#xFA;|sep|okt|n&#xF3;v|des"</code>.
470      * </p>
471      * @param shortMonthNames The value to set to the shortMonthNames property.
472      */
473     public void setShortMonthNames(String shortMonthNames) {
474         this.shortMonthNames = shortMonthNames;
475     }
476 
477     /**
478      * <p>
479      * setter for the serverLanguageCode property.  This property allows
480      * user to specify a
481      * <a href="http://www.ics.uci.edu/pub/ietf/http/related/iso639.txt">
482      * two-letter ISO-639 language code</a> that will be used to
483      * configure the set of month names used by the file timestamp parser.
484      * If neither this nor the {@link #setShortMonthNames(String) shortMonthNames}
485      * is specified, parsing will assume English month names, which may or
486      * may not be significant, depending on whether the date format(s)
487      * specified via {@link  #setDefaultDateFormatStr(String)  defaultDateFormatStr}
488      * and/or {@link  #setRecentDateFormatStr(String)  recentDateFormatStr} are using
489      * numeric or alphabetic month names.
490      * </p>
491      * <p>If the code supplied is not supported here, <code>en_US</code>
492      * month names will be used.  We are supporting here those language
493      * codes which, when a <code> java.util.Locale</code> is constucted
494      * using it, and a <code>java.text.SimpleDateFormat</code> is
495      * constructed using that Locale, the array returned by the
496      * SimpleDateFormat's <code>getShortMonths()</code> method consists
497      * solely of three 8-bit ASCII character strings.  Additionally,
498      * languages which do not meet this requirement are included if a
499      * common alternative set of short month names is known to be used.
500      * This means that users who can tell us of additional such encodings
501      * may get them added to the list of supported languages by contacting
502      * the Apache Commons Net team.
503      * </p>
504      * <p><strong>
505      * Please note that this attribute will NOT be used to determine a
506      * locale-based date format for the language.  </strong>
507      * Experience has shown that many if not most FTP servers outside the
508      * United States employ the standard <code>en_US</code> date format
509      * orderings of <code>MMM d yyyy</code> and <code>MMM d HH:mm</code>
510      * and attempting to deduce this automatically here would cause more
511      * problems than it would solve.  The date format must be changed
512      * via the {@link  #setDefaultDateFormatStr(String)  defaultDateFormatStr} and/or
513      * {@link  #setRecentDateFormatStr(String)  recentDateFormatStr} parameters.
514      * </p>
515      * @param serverLanguageCode The value to set to the serverLanguageCode property.
516      */
517     public void setServerLanguageCode(String serverLanguageCode) {
518         this.serverLanguageCode = serverLanguageCode;
519     }
520 
521     /**
522      * Looks up the supplied language code in the internally maintained table of
523      * language codes.  Returns a DateFormatSymbols object configured with
524      * short month names corresponding to the code.  If there is no corresponding
525      * entry in the table, the object returned will be that for
526      * <code>Locale.US</code>
527      * @param languageCode See {@link  #setServerLanguageCode(String)  serverLanguageCode}
528      * @return a DateFormatSymbols object configured with short month names
529      * corresponding to the supplied code, or with month names for
530      * <code>Locale.US</code> if there is no corresponding entry in the internal
531      * table.
532      */
533     public static DateFormatSymbols lookupDateFormatSymbols(String languageCode)
534     {
535         Object lang = LANGUAGE_CODE_MAP.get(languageCode);
536         if (lang != null) {
537             if (lang instanceof Locale) {
538                 return new DateFormatSymbols((Locale) lang);
539             } else if (lang instanceof String){
540                 return getDateFormatSymbols((String) lang);
541             }
542         }
543         return new DateFormatSymbols(Locale.US);
544     }
545 
546     /**
547      * Returns a DateFormatSymbols object configured with short month names
548      * as in the supplied string
549      * @param shortmonths This  should be as described in
550      *  {@link  #setShortMonthNames(String)  shortMonthNames}
551      * @return a DateFormatSymbols object configured with short month names
552      * as in the supplied string
553      */
554     public static DateFormatSymbols getDateFormatSymbols(String shortmonths)
555     {
556         String[] months = splitShortMonthString(shortmonths);
557         DateFormatSymbols dfs = new DateFormatSymbols(Locale.US);
558         dfs.setShortMonths(months);
559         return dfs;
560     }
561 
562     private static String[] splitShortMonthString(String shortmonths) {
563         StringTokenizer st = new StringTokenizer(shortmonths, "|");
564         int monthcnt = st.countTokens();
565         if (12 != monthcnt) {
566             throw new IllegalArgumentException(
567                     "expecting a pipe-delimited string containing 12 tokens");
568         }
569         String[] months = new String[13];
570         int pos = 0;
571         while(st.hasMoreTokens()) {
572             months[pos++] = st.nextToken();
573         }
574         months[pos]="";
575         return months;
576     }
577 
578     /**
579      * Returns a Collection of all the language codes currently supported
580      * by this class. See {@link  #setServerLanguageCode(String)  serverLanguageCode}
581      * for a functional descrption of language codes within this system.
582      *
583      * @return a Collection of all the language codes currently supported
584      * by this class
585      */
586     public static Collection<String> getSupportedLanguageCodes() {
587         return LANGUAGE_CODE_MAP.keySet();
588     }
589 
590 
591 }