inserting a footer into a pdf

[Vishnu]

Hi group

The question may sound too newbish,do excuse me

Iam a Livelink developer and not exactly familiar with Java.And i need
to implement the following functionality.

-> I have large number of pdf documents.I need to insert a small text
as footer into each page of the pdf documents.

Are there libraries which are available *free*,and which can do this
exact functionality?

(I checked out some libraries which actually enables you to create a
new pdf file.So i thought of implementing this by copying the whole
content of the old one into a new file and then inserting footer into
the new one.But then,wont i loose the original formatting information
if the original document doesnt contain any footers?And wont it
overwrite any original footers present?)

Thanks in advance for any pointers.

-Vishnu-