Yes it is possible, using the SWDIO and SWDCLK pads. I programmed one to operate with MySensors using a black magic probe, but the J-Link also supports SWD programming. The tricky part is connecting to the pads. I just soldered on some wires -- not a very elegant solution, but it worked. You can get a reasonably priced J-Link EDU from Adafruit: https://www.adafruit.com/product/3571