I don't think there is an available API for that... Because I ever did that kind of accessing Excel file in an client-server Swing-based application... I use the old traditional technique that read the file by using java.io package and java.util.Tokenizer class to divide each token... Later save them to the database again...
It's easy to do that way...
But if we can find an API for processing such kind of documents, it'll be easier to apply...
Co-author of SCMAD Exam Guide, Author of JMADPlus
SCJP1.2, CCNA, SCWCD1.4, SCBCD1.3, SCMAD1.0, SCJA1.0, SCJP6.0