How do I read a file created by program X in Java?
John Zukowski There is no magic in Java that lets it automatically know how to read files created by other programs. Basically, find a definition of what the format is, then read the file in. It is your job to read in the file according to the format documentation you've found. You'll have to worry about things like endian order for numerics, character size, and versioning, as file formats tend to change between versions of the program.
Lots of times, other programs support exporting of data to a format that Java does support, usually through an ODBC driver.