Finally got all my paperwork together.

Just before I submit the paperwork and get my visa, one question.

After I enter Japan and establish my residency, can I leave again? I will be working in China and commuting back and forth between Canada, China & Japan with other countries thrown into the mix on occasion.

I have been informed that once I am issued a visa, I must activate the visa within 6 months (by entering Japan and registering) but no where does it say I have to STAY in Japan.