Such filters can be used for 輸出（する）ing a content.
Of course it's possible to 連合させる it with the service ImportFilter
if 輸入する functionality should be 利用できる at same 実施 too.
It's used to filter a 文書 at saving time.
The source 文書 should be already setted by using another interface
XExporter which is supported by this service too.
Tip:
If same 実施 供給するs the service ImportFilter too,
code must distinguish between filtering from a source 文書 (for 輸出（する）) or
filtering to a 的 文書 (for 輸入する). This can be 認めるd by saving
明言する／公表する of used interfaces XExporter or XImporter!
さもなければ it's not （疑いを）晴らす which 活動／戦闘 is 要求するd here.
support initialization of filter with its own configuration
A filter 反対する must be created by 全世界の service FilterFactory.
If filter supports this optional interface, he will be initialized by the factory 直接／まっすぐに
after 創造. The factory will pass follow （警察などへの）密告，告訴（状）s to this new instance:
first item will be a 始める，決める of configuration data of the filter
This 内部の filter 指名する can be used on service FilterFactory
to get その上の （警察などへの）密告，告訴（状）s about it (e.g. his 登録 for mime types or 拡張s etc.)
It's important that returned string is the "内部の 指名する" of the filter which must be
unambigous against all other 登録（する）d filter in 現在の instalation.
Attention!
Supported method setName() sould be ignored or 今後d to the FilterFactory.
It's not 許すd to 始める，決める it 直接／まっすぐに to the configuration. Because it depends
from real 実施 of the FilterFactory if it will be 許すd or not!
