I used a mock tests from https://enthuware.com/java-certification-mock-exams/oracle-certified-associate/ocajp-1z0-808 for preparation. It costs 10$ but it worth it. More on reddit.com

You have to make the best decision you believe is right for you, but I don't put much weight into a programming certificate. I prefer programmers build their portfolios via sites like GitHub and answer questions on sites like this or Stackoverflow. Once you come to an interview, I always give a simple programming project and a few programming scenarios-type questions. I do things like look at people's Github code and see how structured things are and if they have some kind of logical flow. I also try to see if they are active on Stackoverflow. They don't have to ask or answer questions, but I do look to see if they answer or ask questions. I am happy if they say they don't answer or ask many questions, but they use the site to find answers when needed. More on reddit.com

No idea if it will help your hiring prospects. But, the disciplined study of a series of segments of Java required for the certification will help you be a better programmer. I'm OCAJP 7 certified. More on reddit.com

Most Java certifications scream "I'm insecure about my skills" in a lot of hiring departments, and offer dubious value. I wouldn't.

That being said the EE cert used to be a good idea. Now...not so much.

Learning the shit it covers isn't a bad idea though.

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