Not sure if it's just my naivity (stupidity or whatever) but I am having a bit of a drama reading the database file provided.
I attempted to browse through it using a text editor so I could get an idea of the format. However wordpad and notepad fails to recognise a lot of the characters - particularly in the header. I had similar problems when I tried viewing it in vi on linux. (e.g. first line of header looks something like this:
Is this normal? Will it make more sense when a java program reads the bytes in? Do I need to change the character encoding or something... or do I have a corrupted file?
In your instructions, you should have a section describing the data file format. Where it uses the terminology: 4 byte numeric, for example, that is where the file contains binary data and not ASCII text. You have to choose classes from the java io packages which have the appropriate methods available to read from and write to the file in binary format.
In fact, if you read the data file format section in detail it possibly tells you what classes use the the format.