@Override
    public void read(JmeImporter im) throws IOException {
        super.read(im);
        InputCapsule capsule = im.getCapsule(this);
        radius = capsule.readFloat("radius", 0.5f);
        createShape();
    }
creates a SphereCollisionShape with the given radius

@param radius the desired radius (in unscaled units)
jme3-jbullet/src/main/java/com/jme3/bullet/collision/shapes/SphereCollisionShape.java