Java tutorial
/* * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. * The ASF licenses this file to You under the Apache License, Version 2.0 * (the "License"); you may not use this file except in compliance with * the License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package org.apache.commons.net.ftp; import java.text.DateFormatSymbols; import java.util.Collection; import java.util.Locale; import java.util.Map; import java.util.StringTokenizer; import java.util.TreeMap; /** * <p> * This class implements an alternate means of configuring the * {@link org.apache.commons.net.ftp.FTPClient FTPClient} object and * also subordinate objects which it uses. Any class implementing the * {@link org.apache.commons.net.ftp.Configurable Configurable } * interface can be configured by this object. * </p><p> * In particular this class was designed primarily to support configuration * of FTP servers which express file timestamps in formats and languages * other than those for the US locale, which although it is the most common * is not universal. Unfortunately, nothing in the FTP spec allows this to * be determined in an automated way, so manual configuration such as this * is necessary. * </p><p> * This functionality was designed to allow existing clients to work exactly * as before without requiring use of this component. This component should * only need to be explicitly invoked by the user of this package for problem * cases that previous implementations could not solve. * </p> * <h3>Examples of use of FTPClientConfig</h3> * Use cases: * You are trying to access a server that * <ul> * <li>lists files with timestamps that use month names in languages other * than English</li> * <li>lists files with timestamps that use date formats other * than the American English "standard" <code>MM dd yyyy</code></li> * <li>is in different timezone and you need accurate timestamps for * dependency checking as in Ant</li> * </ul> * <p> * Unpaged (whole list) access on a UNIX server that uses French month names * but uses the "standard" <code>MMM d yyyy</code> date formatting * <pre> * FTPClient f=FTPClient(); * FTPClientConfig conf = new FTPClientConfig(FTPClientConfig.SYST_UNIX); * conf.setServerLanguageCode("fr"); * f.configure(conf); * f.connect(server); * f.login(username, password); * FTPFile[] files = listFiles(directory); * </pre> * </p> * <p> * Paged access on a UNIX server that uses Danish month names * and "European" date formatting in Denmark's time zone, when you * are in some other time zone. * <pre> * FTPClient f=FTPClient(); * FTPClientConfig conf = new FTPClientConfig(FTPClientConfig.SYST_UNIX); * conf.setServerLanguageCode("da"); * conf.setDefaultDateFormat("d MMM yyyy"); * conf.setRecentDateFormat("d MMM HH:mm"); * conf.setTimeZoneId("Europe/Copenhagen"); * f.configure(conf); * f.connect(server); * f.login(username, password); * FTPListParseEngine engine = * f.initiateListParsing("com.whatever.YourOwnParser", directory); * * while (engine.hasNext()) { * FTPFile[] files = engine.getNext(25); // "page size" you want * //do whatever you want with these files, display them, etc. * //expensive FTPFile objects not created until needed. * } * </pre> * </p> * <p> * Unpaged (whole list) access on a VMS server that uses month names * in a language not {@link #getSupportedLanguageCodes() supported} by the system. * but uses the "standard" <code>MMM d yyyy</code> date formatting * <pre> * FTPClient f=FTPClient(); * FTPClientConfig conf = new FTPClientConfig(FTPClientConfig.SYST_VMS); * conf.setShortMonthNames( * "jan|feb|mar|apr|ma\u00ED|j\u00FAn|j\u00FAl|\u00e1g\u00FA|sep|okt|n\u00F3v|des"); * f.configure(conf); * f.connect(server); * f.login(username, password); * FTPFile[] files = listFiles(directory); * </pre> * </p> * <p> * Unpaged (whole list) access on a Windows-NT server in a different time zone. * (Note, since the NT Format uses numeric date formatting, language issues * are irrelevant here). * <pre> * FTPClient f=FTPClient(); * FTPClientConfig conf = new FTPClientConfig(FTPClientConfig.SYST_NT); * conf.setTimeZoneId("America/Denver"); * f.configure(conf); * f.connect(server); * f.login(username, password); * FTPFile[] files = listFiles(directory); * </pre> * </p> * Unpaged (whole list) access on a Windows-NT server in a different time zone * but which has been configured to use a unix-style listing format. * <pre> * FTPClient f=FTPClient(); * FTPClientConfig conf = new FTPClientConfig(FTPClientConfig.SYST_UNIX); * conf.setTimeZoneId("America/Denver"); * f.configure(conf); * f.connect(server); * f.login(username, password); * FTPFile[] files = listFiles(directory); * </pre> * * @since 1.4 * @see org.apache.commons.net.ftp.Configurable * @see org.apache.commons.net.ftp.FTPClient * @see org.apache.commons.net.ftp.parser.FTPTimestampParserImpl#configure(FTPClientConfig) * @see org.apache.commons.net.ftp.parser.ConfigurableFTPFileEntryParserImpl */ public class FTPClientConfig { /** * Identifier by which a unix-based ftp server is known throughout * the commons-net ftp system. */ public static final String SYST_UNIX = "UNIX"; /** * Identifier by which a vms-based ftp server is known throughout * the commons-net ftp system. */ public static final String SYST_VMS = "VMS"; /** * Identifier by which a WindowsNT-based ftp server is known throughout * the commons-net ftp system. */ public static final String SYST_NT = "WINDOWS"; /** * Identifier by which an OS/2-based ftp server is known throughout * the commons-net ftp system. */ public static final String SYST_OS2 = "OS/2"; /** * Identifier by which an OS/400-based ftp server is known throughout * the commons-net ftp system. */ public static final String SYST_OS400 = "OS/400"; /** * Identifier by which an AS/400-based ftp server is known throughout * the commons-net ftp system. */ public static final String SYST_AS400 = "AS/400"; /** * Identifier by which an MVS-based ftp server is known throughout * the commons-net ftp system. */ public static final String SYST_MVS = "MVS"; /** * Some servers return an "UNKNOWN Type: L8" message * in response to the SYST command. We set these to be a Unix-type system. * This may happen if the ftpd in question was compiled without system * information. * * NET-230 - Updated to be UPPERCASE so that the check done in * createFileEntryParser will succeed. * * @since 1.5 */ public static final String SYST_L8 = "TYPE: L8"; /** * Identifier by which an Netware-based ftp server is known throughout * the commons-net ftp system. * * @since 1.5 */ public static final String SYST_NETWARE = "NETWARE"; /** * Identifier by which a Mac pre OS-X -based ftp server is known throughout * the commons-net ftp system. * * @since 3.1 */ // Full string is "MACOS Peter's Server"; the substring below should be enough public static final String SYST_MACOS_PETER = "MACOS PETER"; // NET-436 private final String serverSystemKey; private String defaultDateFormatStr = null; private String recentDateFormatStr = null; private boolean lenientFutureDates = true; // NET-407 private String serverLanguageCode = null; private String shortMonthNames = null; private String serverTimeZoneId = null; /** * The main constructor for an FTPClientConfig object * @param systemKey key representing system type of the server being * connected to. See {@link #getServerSystemKey() serverSystemKey} */ public FTPClientConfig(String systemKey) { this.serverSystemKey = systemKey; } /** * Convenience constructor mainly for use in testing. * Constructs a UNIX configuration. */ public FTPClientConfig() { this(SYST_UNIX); } /** * Constructor which allows setting of all member fields * @param systemKey key representing system type of the server being * connected to. See * {@link #getServerSystemKey() serverSystemKey} * @param defaultDateFormatStr See * {@link #setDefaultDateFormatStr(String) defaultDateFormatStr} * @param recentDateFormatStr See * {@link #setRecentDateFormatStr(String) recentDateFormatStr} * @param serverLanguageCode See * {@link #setServerLanguageCode(String) serverLanguageCode} * @param shortMonthNames See * {@link #setShortMonthNames(String) shortMonthNames} * @param serverTimeZoneId See * {@link #setServerTimeZoneId(String) serverTimeZoneId} */ public FTPClientConfig(String systemKey, String defaultDateFormatStr, String recentDateFormatStr, String serverLanguageCode, String shortMonthNames, String serverTimeZoneId) { this(systemKey); this.defaultDateFormatStr = defaultDateFormatStr; this.recentDateFormatStr = recentDateFormatStr; this.serverLanguageCode = serverLanguageCode; this.shortMonthNames = shortMonthNames; this.serverTimeZoneId = serverTimeZoneId; } private static final Map<String, Object> LANGUAGE_CODE_MAP = new TreeMap<String, Object>(); static { // if there are other commonly used month name encodings which // correspond to particular locales, please add them here. // many locales code short names for months as all three letters // these we handle simply. LANGUAGE_CODE_MAP.put("en", Locale.ENGLISH); LANGUAGE_CODE_MAP.put("de", Locale.GERMAN); LANGUAGE_CODE_MAP.put("it", Locale.ITALIAN); LANGUAGE_CODE_MAP.put("es", new Locale("es", "", "")); // spanish LANGUAGE_CODE_MAP.put("pt", new Locale("pt", "", "")); // portuguese LANGUAGE_CODE_MAP.put("da", new Locale("da", "", "")); // danish LANGUAGE_CODE_MAP.put("sv", new Locale("sv", "", "")); // swedish LANGUAGE_CODE_MAP.put("no", new Locale("no", "", "")); // norwegian LANGUAGE_CODE_MAP.put("nl", new Locale("nl", "", "")); // dutch LANGUAGE_CODE_MAP.put("ro", new Locale("ro", "", "")); // romanian LANGUAGE_CODE_MAP.put("sq", new Locale("sq", "", "")); // albanian LANGUAGE_CODE_MAP.put("sh", new Locale("sh", "", "")); // serbo-croatian LANGUAGE_CODE_MAP.put("sk", new Locale("sk", "", "")); // slovak LANGUAGE_CODE_MAP.put("sl", new Locale("sl", "", "")); // slovenian // some don't LANGUAGE_CODE_MAP.put("fr", "jan|f\u00e9v|mar|avr|mai|jun|jui|ao\u00fb|sep|oct|nov|d\u00e9c"); //french } /** * Getter for the serverSystemKey property. This property * specifies the general type of server to which the client connects. * Should be either one of the <code>FTPClientConfig.SYST_*</code> codes * or else the fully qualified class name of a parser implementing both * the <code>FTPFileEntryParser</code> and <code>Configurable</code> * interfaces. * @return Returns the serverSystemKey property. */ public String getServerSystemKey() { return serverSystemKey; } /** * getter for the {@link #setDefaultDateFormatStr(String) defaultDateFormatStr} * property. * @return Returns the defaultDateFormatStr property. */ public String getDefaultDateFormatStr() { return defaultDateFormatStr; } /** * getter for the {@link #setRecentDateFormatStr(String) recentDateFormatStr} property. * @return Returns the recentDateFormatStr property. */ public String getRecentDateFormatStr() { return recentDateFormatStr; } /** * getter for the {@link #setServerTimeZoneId(String) serverTimeZoneId} property. * @return Returns the serverTimeZoneId property. */ public String getServerTimeZoneId() { return serverTimeZoneId; } /** * <p> * getter for the {@link #setShortMonthNames(String) shortMonthNames} * property. * </p> * @return Returns the shortMonthNames. */ public String getShortMonthNames() { return shortMonthNames; } /** * <p> * getter for the {@link #setServerLanguageCode(String) serverLanguageCode} property. * </p> * @return Returns the serverLanguageCode property. */ public String getServerLanguageCode() { return serverLanguageCode; } /** * <p> * getter for the {@link #setLenientFutureDates(boolean) lenientFutureDates} property. * </p> * @return Returns the lenientFutureDates. * @since 1.5 */ public boolean isLenientFutureDates() { return lenientFutureDates; } /** * <p> * setter for the defaultDateFormatStr property. This property * specifies the main date format that will be used by a parser configured * by this configuration to parse file timestamps. If this is not * specified, such a parser will use as a default value, the most commonly * used format which will be in as used in <code>en_US</code> locales. * </p><p> * This should be in the format described for * <code>java.text.SimpleDateFormat</code>. * property. * </p> * @param defaultDateFormatStr The defaultDateFormatStr to set. */ public void setDefaultDateFormatStr(String defaultDateFormatStr) { this.defaultDateFormatStr = defaultDateFormatStr; } /** * <p> * setter for the recentDateFormatStr property. This property * specifies a secondary date format that will be used by a parser * configured by this configuration to parse file timestamps, typically * those less than a year old. If this is not specified, such a parser * will not attempt to parse using an alternate format. * </p> * <p> * This is used primarily in unix-based systems. * </p> * <p> * This should be in the format described for * <code>java.text.SimpleDateFormat</code>. * </p> * @param recentDateFormatStr The recentDateFormatStr to set. */ public void setRecentDateFormatStr(String recentDateFormatStr) { this.recentDateFormatStr = recentDateFormatStr; } /** * <p> * setter for the lenientFutureDates property. This boolean property * (default: false) only has meaning when a * {@link #setRecentDateFormatStr(String) recentDateFormatStr} property * has been set. In that case, if this property is set true, then the * parser, when it encounters a listing parseable with the recent date * format, will only consider a date to belong to the previous year if * it is more than one day in the future. This will allow all * out-of-synch situations (whether based on "slop" - i.e. servers simply * out of synch with one another or because of time zone differences - * but in the latter case it is highly recommended to use the * {@link #setServerTimeZoneId(String) serverTimeZoneId} property * instead) to resolve correctly. * </p><p> * This is used primarily in unix-based systems. * </p> * @param lenientFutureDates set true to compensate for out-of-synch * conditions. */ public void setLenientFutureDates(boolean lenientFutureDates) { this.lenientFutureDates = lenientFutureDates; } /** * <p> * setter for the serverTimeZoneId property. This property * allows a time zone to be specified corresponding to that known to be * used by an FTP server in file listings. This might be particularly * useful to clients such as Ant that try to use these timestamps for * dependency checking. * </p><p> * This should be one of the identifiers used by * <code>java.util.TimeZone</code> to refer to time zones, for example, * <code>America/Chicago</code> or <code>Asia/Rangoon</code>. * </p> * @param serverTimeZoneId The serverTimeZoneId to set. */ public void setServerTimeZoneId(String serverTimeZoneId) { this.serverTimeZoneId = serverTimeZoneId; } /** * <p> * setter for the shortMonthNames property. * This property allows the user to specify a set of month names * used by the server that is different from those that may be * specified using the {@link #setServerLanguageCode(String) serverLanguageCode} * property. * </p><p> * This should be a string containing twelve strings each composed of * three characters, delimited by pipe (|) characters. Currently, * only 8-bit ASCII characters are known to be supported. For example, * a set of month names used by a hypothetical Icelandic FTP server might * conceivably be specified as * <code>"jan|feb|mar|apr|maí|jún|júl|ágú|sep|okt|nóv|des"</code>. * </p> * @param shortMonthNames The value to set to the shortMonthNames property. */ public void setShortMonthNames(String shortMonthNames) { this.shortMonthNames = shortMonthNames; } /** * <p> * setter for the serverLanguageCode property. This property allows * user to specify a * <a href="http://www.ics.uci.edu/pub/ietf/http/related/iso639.txt"> * two-letter ISO-639 language code</a> that will be used to * configure the set of month names used by the file timestamp parser. * If neither this nor the {@link #setShortMonthNames(String) shortMonthNames} * is specified, parsing will assume English month names, which may or * may not be significant, depending on whether the date format(s) * specified via {@link #setDefaultDateFormatStr(String) defaultDateFormatStr} * and/or {@link #setRecentDateFormatStr(String) recentDateFormatStr} are using * numeric or alphabetic month names. * </p> * <p>If the code supplied is not supported here, <code>en_US</code> * month names will be used. We are supporting here those language * codes which, when a <code> java.util.Locale</code> is constucted * using it, and a <code>java.text.SimpleDateFormat</code> is * constructed using that Locale, the array returned by the * SimpleDateFormat's <code>getShortMonths()</code> method consists * solely of three 8-bit ASCII character strings. Additionally, * languages which do not meet this requirement are included if a * common alternative set of short month names is known to be used. * This means that users who can tell us of additional such encodings * may get them added to the list of supported languages by contacting * the Apache Commons Net team. * </p> * <p><strong> * Please note that this attribute will NOT be used to determine a * locale-based date format for the language. </strong> * Experience has shown that many if not most FTP servers outside the * United States employ the standard <code>en_US</code> date format * orderings of <code>MMM d yyyy</code> and <code>MMM d HH:mm</code> * and attempting to deduce this automatically here would cause more * problems than it would solve. The date format must be changed * via the {@link #setDefaultDateFormatStr(String) defaultDateFormatStr} and/or * {@link #setRecentDateFormatStr(String) recentDateFormatStr} parameters. * </p> * @param serverLanguageCode The value to set to the serverLanguageCode property. */ public void setServerLanguageCode(String serverLanguageCode) { this.serverLanguageCode = serverLanguageCode; } /** * Looks up the supplied language code in the internally maintained table of * language codes. Returns a DateFormatSymbols object configured with * short month names corresponding to the code. If there is no corresponding * entry in the table, the object returned will be that for * <code>Locale.US</code> * @param languageCode See {@link #setServerLanguageCode(String) serverLanguageCode} * @return a DateFormatSymbols object configured with short month names * corresponding to the supplied code, or with month names for * <code>Locale.US</code> if there is no corresponding entry in the internal * table. */ public static DateFormatSymbols lookupDateFormatSymbols(String languageCode) { Object lang = LANGUAGE_CODE_MAP.get(languageCode); if (lang != null) { if (lang instanceof Locale) { return new DateFormatSymbols((Locale) lang); } else if (lang instanceof String) { return getDateFormatSymbols((String) lang); } } return new DateFormatSymbols(Locale.US); } /** * Returns a DateFormatSymbols object configured with short month names * as in the supplied string * @param shortmonths This should be as described in * {@link #setShortMonthNames(String) shortMonthNames} * @return a DateFormatSymbols object configured with short month names * as in the supplied string */ public static DateFormatSymbols getDateFormatSymbols(String shortmonths) { String[] months = splitShortMonthString(shortmonths); DateFormatSymbols dfs = new DateFormatSymbols(Locale.US); dfs.setShortMonths(months); return dfs; } private static String[] splitShortMonthString(String shortmonths) { StringTokenizer st = new StringTokenizer(shortmonths, "|"); int monthcnt = st.countTokens(); if (12 != monthcnt) { throw new IllegalArgumentException("expecting a pipe-delimited string containing 12 tokens"); } String[] months = new String[13]; int pos = 0; while (st.hasMoreTokens()) { months[pos++] = st.nextToken(); } months[pos] = ""; return months; } /** * Returns a Collection of all the language codes currently supported * by this class. See {@link #setServerLanguageCode(String) serverLanguageCode} * for a functional descrption of language codes within this system. * * @return a Collection of all the language codes currently supported * by this class */ public static Collection<String> getSupportedLanguageCodes() { return LANGUAGE_CODE_MAP.keySet(); } }