Data data = new Data(buffer, 0, 31, true);
assertEquals(31, data.written());
assertEquals(31, data.readable());
assertEquals(4, data.debug_GetBuffer().length);
assertEquals(0, data.debug_GetRead());
assertEquals(31, data.debug_GetWrite());
assertEquals(RT.EOF, data.debug_GetMark());
BigInteger value = data.read(31, false);