@Override
    public double getLength() {
        return length;
    }
Sets the translations, rotations, and/or scales.

@param times        the desired time for each keyframe,
                    or null to leave the times unchanged
@param translations the desired translation of the target for each
                    keyframe (same length as times)
                    or null to leave the translations unchanged
@param rotations    the desired rotation of the target for each keyframe
                    (same length as times)
                    or null to leave the rotations unchanged
@param scales       the desired scale of the target for each keyframe
                    (same length as times)
                    or null to leave the scales unchanged
jme3-core/src/main/java/com/jme3/anim/TransformTrack.java