Foreigners giving birth in Japan

If a foreign woman gives birth while visiting Japan, will that child automatically be a Japanese citizen or a citizen of that woman's country of citizenship?

What about children born to American military stationed in Japan? Will they be Japanese or American citizens?

Not enough information, really, but I'll make a few assumptions.

If you are not married to a Japanese, then having a baby in Japan does not automatically give Japanese citizenship to the baby.
If you are married to a Japanese, then it is automatic.

Japan doesn't recognize the location (i.e., country) where one is born, so even being born on a US military base in Japan would not be sufficient to grant Japanese citizenship unless one parent is Japanese.

Japan does not use jus soli and instead operates on jus sanguinis

In the case of children born to American military personnel (or any other American citizen) in Japan, the child's birth should be registered through the American Embassy, which will cause to be issued a document titled something like "Consular Report of Birth of American Citizen Abroad". This document serves as a de facto birth certificate. Citizens born overseas do not receive birth certificates in the usual sense, as they are documents issued by the Bureau of Vital Statistics (or equivalent) in individual states. Not having been born in a U.S. state, no such certificate can be issued. In short: Hang onto the certificate; it is the child's birth certificate (in all but name).

Okay, I understand. Thank you guys.