From https://bugs.eclipse.org/bugs/show_bug.cgi?id=204740 :
The Commons Net FTP Entry Parsers do not preserve trailing whitespace on file names. On systems like UNIX that support trailing whitespace, this results in some invalid entries being parsed.
The bug seems to be in Jakarta Commons Net UnixFTPEntryParser – in its REGEX,
the last field ("endtoken") is declared
which means any whitespace followed by at least one non-whitespace character.
Which is not the case in case of trailing whitespace.