Uploading and Retrieving Excel file on Server and Client?

Hello everyone.
I am new to this Forum and new to Web System as well.
I have 2 questions regarding my current work. I will use Servlet and JSP on server side.
1:
The User needs to select a excel file from the local computer in the browser, then click the UPLOAD button to submit the request to the server. The server will copy the excel file from the client to the server, then update the database according to the records in the excel file.
How to achieve this? Do I use MultipartParser class? Can Servlet/JSP extract data easily from Excel files?
2:
The user needs to view the whole table data from a database on the client computer, in Excel.
How to do this? I use JDBC to extract all data from the database, then format the data in Html page on the server side?
How to let Excel show all the columns listed just like the real database?
Any suggestion is welcome. Thanks.

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Sun Certified Programmer for Java Platform