private static byte expectedNorm(final DefaultSimilarity sim,final int length,final float boost){
  return (byte)sim.encodeNormValue(boost / ((float)Math.sqrt(length)));
}

private static byte expectedNorm ( final DefaultSimilarity sim , final int length , final float boost ) { return ( byte ) sim . encodeNormValue ( boost / ( ( float ) Math . sqrt ( length ) ) ) ; }
given a length , and boost returns the expected encoded norm
