Starting April 1 you'll earn AAdvantage EQMs/EQPs when you fly JAL and credit the flight to AAdvantage. Before April 1 you have to fly an AA-coded JAL flight (codeshare) to get AAdvantage EQMs/EQPs, and the AA flight number has to be on your boarding pass.

It's unclear how JAL miles will translate into AAdvantage EQMs/EQPs. I can explain how JAL does it, though. JAL only has EQPs (called FLY ON points) for JAL Mileage Bank members, and the number of FLY ON points you get is pretty complicated. For JMB you get 2 FLY ON points per mile for Japanese domestic flights, 1.5 FLY ON points per mile for Japan-China flights, and 1 FLY ON point per mile for everything else (including long distance international). There's a 25% class of service bonus for business class and 50% for first class. Discount economy fares earn only 70% of flight mileage. There is no minimum number of FLY ON points per flight: a short flight yields very few FLY ON points.