Japan police certificate

Hi everyone!
I'm working in Japan from 2012 - 2015
I overstay in Japan 1 month,after i finished the contract with my company and then i go to immigration center and talk to them: "i want to go back my country" affter 15 days i can go to my country, now i want to take the police certificate in Japan for apply PR in Germany. Now i worry when i overstay in Japan that is criminal record or no? Sorry because my English not good, thanks a lot!.

Depend how you left Japan.
You left voluntarily than you are recorded as overstay but you left on your own.
In Japan (many other countries also) overstay is treated as a crime.

You can just apply a certificate and see what you will receive.

How can you know ? Can you show me some website? I would like to check that information. Thanks a lot.

Call or visit Japanese embassy where you live now.

This is the HP of The Tokyo Metropolitan Police Department (TMPD).
https://www.keishicho.metro.tokyo.jp/multilingual/english/finding_serv...
(Even if living overseas, you can apply to public agencies of Japan such as the local Japanese embassy or consulate in the country where you live.)

Thanks a lot!