Germany surrendered in May 1945, before the Trinity test. But in the earlier planning stages, were any German targets considered before the surrender? Also, was there any preference given to German vs Japanese targets?
There were no serious German targets considered. Even very early on, the attention was on Japan for a variety of reasons. This does not mean that, if the timing had been different, that they wouldn't have used it in the European theatre (even though that would have created a lot of logistical difficulties, since they didn't have B-29s deployed there). But from a planning perspective, they never really did make any assumptions that Germany would be a target, and by the time they started doing really concrete targeting choices (e.g., looking at question of actual use), they already were projecting that Germany would be out of the picture before the bombs were ready.
For more discussion and documents, see what I have written here.