Welcome again
What makes you think that C isn't a good language in terms of employment opportunities? Let's look at the
Tiobe index; notice that Java® is currently well in the lead and C is second. So there are likely to be lots of C jobs going. Things like operating systems and virtual machines and database programs are often written in C.
I am afraid that C is probably not a good foundation for learning Java®, no more than learning German would be for learning Italian. The two languages are completely unrelated, except that their syntax looks similar, and it is hazardous to think that similar syntax represents similar meaning or similar semantics, because they don't.
Does your C book cover things like this?
That code is actually incorrect, but it does show the sort of thing the C chappies like to write with very terse syntax and use of pointers. You have to learn that sort of pointer arithmetic before you can claim to have any serious knowledge of C.