public final Vector3f getHalfExtents() {
        return halfExtents;
    }
Creates a cylinder shape around the given axis from the given halfextents
@param halfExtents the halfextents to use
@param axis (0=X,1=Y,2=Z)
jme3-jbullet/src/main/java/com/jme3/bullet/collision/shapes/CylinderCollisionShape.java