I've recently become an OCP Java Programmer and I'm wondering if it's worth going for one (or more) of the certifications which have this as a prerequisite.
If there are any good self study books that can be recommended that would be helpful too.
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I am about to take the OCJP exam myself in a few weeks. As you said, this is the prerequisite for all the other exams. The OCJP exam pretty much tests your knowledge of the APIs and language features and doesn't really exercise your programming skills. Secondly, you need to think about what stream your interested in. The certification programme splits into various paths: mobile, web, enterprise etc. So I'd have a think about which stream you are interested in.
If you are just looking for something to enhance your CV for a job then the OCJP may well be enough.
Well done in gettting your OCJP!
I'm about to take the OCPJP certification next Wednesday.
If I pass, I'd think about going for SCWCD, or whatever Oracle calls it these days.
This one seems to cover the most promising aspect of Java development, web development.
(I quoted Jon Skeet's answer to this one because he's like Chuck Norris on the exchange sites and I thought the answer was better than the accepted one...)
You can also find this question answered many times on Stack Overflow. I would encourage you to go to each of the links and read the others responses. I only included the top responses.