Reading and writing xls file to and from database(postgresql) using java

Question

I want to read an MS-Excel file and feed the data to the database(postgreSQL) and I wish to read the data from the database and write it to the MS-Excel file using java.

I've tried for poi api but here is no direct way to transfer the xls contents to database(postgreSQL), also I know about xlsql but the problem is that it can be used with Mysql dialect and HDSQL!