The Brucea javanica comes originally from Java, and much of the surrounding area.
It has been used in Chinese medicine for centuries for treating things like Malaria and parasites, as well as other. There has been limited studies that show it may work, but not enough to really tell.
Medicinal or not, it does make a nice landscape bush, as seen in the San Francisco Botanical Garden of Golden Gate Park 9 June 2022.