They use a Gas Chromotography type test, that they have to send into the lab for (a piss test). It is more accurate than the "dip test" sticks some places use (another piss test). Also, in DEP and throughout the rest of you navy career the drug tests will be observed, so I hope you aren't shy peeing in front of someone. Also, if you are thinking about using "the whizzinator" or "sneaky pete" or one of those other fake wieners, it is highly doubtful you will succeed. Especially at bootcamp. My piss test at boot camp consisted of about 6 or 7 us in a row and we had to drop our pants to our knees and lift our shirts above our nipples and stand there like that until they told us to pee, which was about 20 seconds later. I remember one kid couldn't piss and they made him shuffle over to the toliet with his pants down and sit there holding his shirt past his nipples till he could go.
As for follicle tests... no, that is too expensive. Spinal taps are illegal. Blood tests no... I know the saliva test has been gaining popularity in the civilian world, but if they do switch to that it has even less of a detection period.
For detection times visit
www.erowid.org. Keep in mind times may vary and there are ways to marginally speed up the excretion from the body. Do some research. But yeah... you'll only get urine tests. If you do accidentally use while your in report as soon as possible because then it is a medical problem rather than a legal problem.