    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;
    019
    020import java.text.DateFormatSymbols;
    021import java.util.Collection;
    022import java.util.Locale;
    023import java.util.Map;
    024import java.util.StringTokenizer;
    025import java.util.TreeMap;
    026
    027/**
    028 * <p>
    029 * This class implements an alternate means of configuring the
    030 * {@link  org.apache.commons.net.ftp.FTPClient  FTPClient} object and
    031 * also subordinate objects which it uses.  Any class implementing the
    032 * {@link  org.apache.commons.net.ftp.Configurable  Configurable }
    033 * interface can be configured by this object.
    034 * </p><p>
    035 * In particular this class was designed primarily to support configuration
    036 * of FTP servers which express file timestamps in formats and languages
    037 * other than those for the US locale, which although it is the most common
    038 * is not universal.  Unfortunately, nothing in the FTP spec allows this to
    039 * be determined in an automated way, so manual configuration such as this
    040 * is necessary.
    041 * </p><p>
    042 * This functionality was designed to allow existing clients to work exactly
    043 * as before without requiring use of this component.  This component should
    044 * only need to be explicitly invoked by the user of this package for problem
    045 * cases that previous implementations could not solve.
    046 * </p>
    047 * <h3>Examples of use of FTPClientConfig</h3>
    048 * Use cases:
    049 * You are trying to access a server that
    050 * <ul>
    051 * <li>lists files with timestamps that use month names in languages other
    052 * than English</li>
    053 * <li>lists files with timestamps that use date formats other
    054 * than the American English "standard" <code>MM dd yyyy</code></li>
    055 * <li>is in different timezone and you need accurate timestamps for
    056 * dependency checking as in Ant</li>
    057 * </ul>
    058 * <p>
    059 * Unpaged (whole list) access on a UNIX server that uses French month names
    060 * but uses the "standard" <code>MMM d yyyy</code> date formatting
    061 * <pre>
    062 *    FTPClient f=FTPClient();
    063 *    FTPClientConfig conf = new FTPClientConfig(FTPClientConfig.SYST_UNIX);
    064 *    conf.setServerLanguageCode("fr");
    065 *    f.configure(conf);
    066 *    f.connect(server);
    067 *    f.login(username, password);
    068 *    FTPFile[] files = listFiles(directory);
    069 * </pre>
    070 * </p>
    071 * <p>
    072 * Paged access on a UNIX server that uses Danish month names
    073 * and "European" date formatting in Denmark's time zone, when you
    074 * are in some other time zone.
    075 * <pre>
    076 *    FTPClient f=FTPClient();
    077 *    FTPClientConfig conf = new FTPClientConfig(FTPClientConfig.SYST_UNIX);
    078 *    conf.setServerLanguageCode("da");
    079 *    conf.setDefaultDateFormat("d MMM yyyy");
    080 *    conf.setRecentDateFormat("d MMM HH:mm");
    081 *    conf.setTimeZoneId("Europe/Copenhagen");
    082 *    f.configure(conf);
    083 *    f.connect(server);
    084 *    f.login(username, password);
    085 *    FTPListParseEngine engine =
    086 *       f.initiateListParsing("com.whatever.YourOwnParser", directory);
    087 *
    088 *    while (engine.hasNext()) {
    089 *       FTPFile[] files = engine.getNext(25);  // "page size" you want
    090 *       //do whatever you want with these files, display them, etc.
    091 *       //expensive FTPFile objects not created until needed.
    092 *    }
    093 * </pre>
    094 * </p>
    095 * <p>
    096 * Unpaged (whole list) access on a VMS server that uses month names
    097 * in a language not {@link #getSupportedLanguageCodes() supported} by the system.
    098 * but uses the "standard" <code>MMM d yyyy</code> date formatting
    099 * <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 */
    142public 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}