Java for SAP

Dear SAP people,

I am new in SAP and I will be taking some SAP modules (SAP Certifications).

I have noticed that Java is a good skill for some jobs.

So, my question is:

What Java Certification or Certifications would be the best match for me?

In addition, I am thinking of taking courses of HTML, JavaScript, CSS and PHP. is this a good idea? Or it is better if I get SAP courses?

My goal is become a SAP Consultant.

Thanks a lot for any comments and guidance.

Best regards,

Alex