I've taken the train (Pramex) from Jogyakarta to Solo, spent a few days at the Alila (which is amazing value as Cat 1; I thought I wrote a review, but can't find it). Note that the Pramex departs from an ugly station building on the other side of the tracks. Additionally, in Solo, we stopped at a ground-level platform, which necessitated climbing down from the train. Super cheap (8000rp IIRC), on time, and far safer than car travel in Indonesia, but not something I'd want to do with a lot of luggage or if elderly/mobility impaired.