code: @Test public void testAppendNumericBytes(){
    BitArray bits=new BitArray();
    Encoder.appendNumericBytes("1",bits);
    assertEquals(" ...X",bits.toString());
    bits=new BitArray();
    Encoder.appendNumericBytes("12",bits);
    assertEquals(" ...XX..",bits.toString());
    bits=new BitArray();
    Encoder.appendNumericBytes("123",bits);
    assertEquals(" ...XXXX. XX",bits.toString());
    bits=new BitArray();
    Encoder.appendNumericBytes("1234",bits);
    assertEquals(" ...XXXX. XX.X..",bits.toString());
    bits=new BitArray();
    Encoder.appendNumericBytes("",bits);
    assertEquals("",bits.toString());
  }
  