Yes, learn japanese fast.
I am a german, moving to Japan in a few weeks to work there. In the past years I was there up to 6 times a year for business trip, and without knowing japanese, it will be very difficult.
My company sent me to a japanese teacher in Germany, she used a book names "Japanisch im Sauseschritt", it gives you a very fast introduction so that you can understand basics soon.
It teaches Katakana and Hiragana as well, so that you can read the menues and street signs
.
Have fun in Japan.
