If you want to read a dbf  file you can use javadbf at:
https://javadbf.dev.java.net/
If you want to create  DBF file  you can use StelsDBF:
www.jars.com/.../32689
If your mentioned convert task needs to be done once, or needs to be done on specific schedules, may be you prefer to use database specific tools, as an example I remember that SQLServer had some tools for converting data to DBF format. Mean while there are some other tools like DBArtisan www.embarcadero.com/products/dbartisan/index.html which does different kind of import of export. (So no java  code is needed)
There are some open source tools for import/export like Gaudi (www.memoriapersistente.pt/en/opensource/gaudi/).