>To save or delete strings in a textfile which is on my HD is no
>problem but I have no clue how to do it with a text file
>that is on another server.
>Do I need to use a URL and save in into a read/write stream?
You need some assistance from the server. Ideally a Servlet that runs
on the server to do it for you when asked, that tries until the file
is not busy, copying to a new file then renaming.
see http://mindprod.com/fileio.html for how to do the fileio.

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Canadian Mind Products, Roedy Green.
Coaching, problem solving, economical contract programming.
See http://mindprod.com/jgloss/jgloss.html for The Java Glossary.