Simple Octree implementation

Hello I need somebody that can implement an octree in java, node or any language besides ( c++, c, c#, etc).

The octree would represent 3d Space with objects moving around, I would need the octree to be able to add objects with a point and radius (for volume calculation) and posible collisions of objects.

The resulting code would be use to setup an api. Take that into consideration

Any question via chat please