org.apache.commons.net.ftp

Class FTPClientConfig

public class FTPClientConfig extends Object

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.

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.

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.

Examples of use of FTPClientConfig

Use cases: You are trying to access a server that

Unpaged (whole list) access on a UNIX server that uses French month names but uses the "standard" MMM d yyyy date formatting

    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);
 

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.

    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.
    }
 

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" MMM d yyyy date formatting

    FTPClient f=FTPClient();
    FTPClientConfig conf = new FTPClientConfig(FTPClientConfig.SYST_VMS);
    conf.setShortMonthNames(
        "jan|feb|mar|apr|maí|jún|júl|ágú|sep|okt|nóv|des");
    f.configure(conf);
    f.connect(server);
    f.login(username, password);
    FTPFile[] files = listFiles(directory);
 

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).

    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);
 

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.
    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);
 

Since: 1.4

See Also: Configurable FTPClient configure ConfigurableFTPFileEntryParserImpl

Field Summary
static StringSYST_MVS
Identifier by which an MVS-based ftp server is known throughout the commons-net ftp system.
static StringSYST_NT
Identifier by which a WindowsNT-based ftp server is known throughout the commons-net ftp system.
static StringSYST_OS2
Identifier by which an OS/2-based ftp server is known throughout the commons-net ftp system.
static StringSYST_OS400
Identifier by which an OS/400-based ftp server is known throughout the commons-net ftp system.
static StringSYST_UNIX
Identifier by which a unix-based ftp server is known throughout the commons-net ftp system.
static StringSYST_VMS
Identifier by which a vms-based ftp server is known throughout the commons-net ftp system.
Constructor Summary
FTPClientConfig(String systemKey)
The main constructor for an FTPClientConfig object
FTPClientConfig()
Convenience constructor mainly for use in testing.
FTPClientConfig(String systemKey, String defaultDateFormatStr, String recentDateFormatStr, String serverLanguageCode, String shortMonthNames, String serverTimeZoneId)
Constructor which allows setting of all member fields
Method Summary
static DateFormatSymbolsgetDateFormatSymbols(String shortmonths)
Returns a DateFormatSymbols object configured with short month names as in the supplied string
StringgetDefaultDateFormatStr()
getter for the {@link #setDefaultDateFormatStr(String) defaultDateFormatStr} property.
StringgetRecentDateFormatStr()
getter for the {@link #setRecentDateFormatStr(String) recentDateFormatStr} property.
StringgetServerLanguageCode()

getter for the {@link #setServerLanguageCode(String) serverLanguageCode} property.

StringgetServerSystemKey()
Getter for the serverSystemKey property.
StringgetServerTimeZoneId()
getter for the {@link #setServerTimeZoneId(String) serverTimeZoneId} property.
StringgetShortMonthNames()

getter for the {@link #setShortMonthNames(String) shortMonthNames} property.

static CollectiongetSupportedLanguageCodes()
Returns a Collection of all the language codes currently supported by this class.
static DateFormatSymbolslookupDateFormatSymbols(String languageCode)
Looks up the supplied language code in the internally maintained table of language codes.
voidsetDefaultDateFormatStr(String defaultDateFormatStr)

setter for the defaultDateFormatStr property.

voidsetRecentDateFormatStr(String recentDateFormatStr)

setter for the recentDateFormatStr property.

voidsetServerLanguageCode(String serverLanguageCode)

setter for the serverLanguageCode property.

voidsetServerTimeZoneId(String serverTimeZoneId)

setter for the serverTimeZoneId property.

voidsetShortMonthNames(String shortMonthNames)

setter for the shortMonthNames property.

Field Detail

SYST_MVS

public static final String SYST_MVS
Identifier by which an MVS-based ftp server is known throughout the commons-net ftp system.

SYST_NT

public static final String SYST_NT
Identifier by which a WindowsNT-based ftp server is known throughout the commons-net ftp system.

SYST_OS2

public static final String SYST_OS2
Identifier by which an OS/2-based ftp server is known throughout the commons-net ftp system.

SYST_OS400

public static final String SYST_OS400
Identifier by which an OS/400-based ftp server is known throughout the commons-net ftp system.

SYST_UNIX

public static final String SYST_UNIX
Identifier by which a unix-based ftp server is known throughout the commons-net ftp system.

SYST_VMS

public static final String SYST_VMS
Identifier by which a vms-based ftp server is known throughout the commons-net ftp system.

Constructor Detail

FTPClientConfig

public FTPClientConfig(String systemKey)
The main constructor for an FTPClientConfig object

Parameters: systemKey key representing system type of the server being connected to. See {@link #getServerSystemKey() serverSystemKey}

FTPClientConfig

public FTPClientConfig()
Convenience constructor mainly for use in testing. Constructs a UNIX configuration.

FTPClientConfig

public FTPClientConfig(String systemKey, String defaultDateFormatStr, String recentDateFormatStr, String serverLanguageCode, String shortMonthNames, String serverTimeZoneId)
Constructor which allows setting of all member fields

Parameters: systemKey key representing system type of the server being connected to. See {@link #getServerSystemKey() serverSystemKey} defaultDateFormatStr See {@link #setDefaultDateFormatStr(String) defaultDateFormatStr} recentDateFormatStr See {@link #setRecentDateFormatStr(String) recentDateFormatStr} serverLanguageCode See {@link #setServerLanguageCode(String) serverLanguageCode} shortMonthNames See {@link #setShortMonthNames(String) shortMonthNames} serverTimeZoneId See {@link #setServerTimeZoneId(String) serverTimeZoneId}

Method Detail

getDateFormatSymbols

public static DateFormatSymbols getDateFormatSymbols(String shortmonths)
Returns a DateFormatSymbols object configured with short month names as in the supplied string

Parameters: shortmonths This should be as described in {@link #setShortMonthNames(String) shortMonthNames}

Returns: a DateFormatSymbols object configured with short month names as in the supplied string

getDefaultDateFormatStr

public String getDefaultDateFormatStr()
getter for the {@link #setDefaultDateFormatStr(String) defaultDateFormatStr} property.

Returns: Returns the defaultDateFormatStr property.

getRecentDateFormatStr

public String getRecentDateFormatStr()
getter for the {@link #setRecentDateFormatStr(String) recentDateFormatStr} property.

Returns: Returns the recentDateFormatStr property.

getServerLanguageCode

public String getServerLanguageCode()

getter for the {@link #setServerLanguageCode(String) serverLanguageCode} property.

* @return Returns the serverLanguageCode property.

getServerSystemKey

public String getServerSystemKey()
Getter for the serverSystemKey property. This property specifies the general type of server to which the client connects. Should be either one of the FTPClientConfig.SYST_* codes or else the fully qualified class name of a parser implementing both the FTPFileEntryParser and Configurable interfaces.

Returns: Returns the serverSystemKey property.

getServerTimeZoneId

public String getServerTimeZoneId()
getter for the {@link #setServerTimeZoneId(String) serverTimeZoneId} property.

Returns: Returns the serverTimeZoneId property.

getShortMonthNames

public String getShortMonthNames()

getter for the {@link #setShortMonthNames(String) shortMonthNames} property.

Returns: Returns the shortMonthNames.

getSupportedLanguageCodes

public static Collection getSupportedLanguageCodes()
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.

Returns: a Collection of all the language codes currently supported by this class

lookupDateFormatSymbols

public static DateFormatSymbols lookupDateFormatSymbols(String languageCode)
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 Locale.US

Parameters: languageCode See {@link #setServerLanguageCode(String) serverLanguageCode}

Returns: a DateFormatSymbols object configured with short month names corresponding to the supplied code, or with month names for Locale.US if there is no corresponding entry in the internal table.

setDefaultDateFormatStr

public void setDefaultDateFormatStr(String defaultDateFormatStr)

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 en_US locales.

This should be in the format described for java.text.SimpleDateFormat. property.

Parameters: defaultDateFormatStr The defaultDateFormatStr to set.

setRecentDateFormatStr

public void setRecentDateFormatStr(String recentDateFormatStr)

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.

This is used primarily in unix-based systems.

This should be in the format described for java.text.SimpleDateFormat.

Parameters: recentDateFormatStr The recentDateFormatStr to set.

setServerLanguageCode

public void setServerLanguageCode(String serverLanguageCode)

setter for the serverLanguageCode property. This property allows user to specify a two-letter ISO-639 language code 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.

If the code supplied is not supported here, en_US month names will be used. We are supporting here those language codes which, when a java.util.Locale is constucted using it, and a java.text.SimpleDateFormat is constructed using that Locale, the array returned by the SimpleDateFormat's getShortMonths() 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 jakarta-commons-net team.

Please note that this attribute will NOT be used to determine a locale-based date format for the language. Experience has shown that many if not most FTP servers outside the United States employ the standard en_US date format orderings of MMM d yyyy and MMM d HH:mm 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.

Parameters: serverLanguageCode The value to set to the serverLanguageCode property.

setServerTimeZoneId

public void setServerTimeZoneId(String serverTimeZoneId)

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.

This should be one of the identifiers used by java.util.TimeZone to refer to time zones, for example, America/Chicago or Asia/Rangoon.

Parameters: serverTimeZoneId The serverTimeZoneId to set.

setShortMonthNames

public void setShortMonthNames(String shortMonthNames)

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.

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 "jan|feb|mar|apr|maí|jún|júl|ágú|sep|okt|nóv|des".

Parameters: shortMonthNames The value to set to the shortMonthNames property.