There are pros and cons to both. The 1Z0-809 is older but there is more study material available. 1Z0-816 is more recent but you'll have to assemble your own study material.
If you want to showcase what you can do, try to write as much code as you can and build projects. The certificates will be a nice plus but I believe that showing nice projects can also be a big contributing factor.
Oracle Certified Professional Java SE 8
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Building a Better World in your Backyard by Paul Wheaton and Shawn Klassen-Koop