HexCodec { public static String toLowerHex(long v) { char[] data = RecyclableBuffers.parseBuffer(); writeHexLong(data, 0, v); return new String(data, 0, 16); } HexCodec(); static long lowerHexToUnsignedLong(CharSequence lowerHex); static long lowerHexToUnsignedLong(CharSequence value, int beginIndex); static long lenientLowerHexToUnsignedLong(CharSequence value, int beginIndex,
    int endIndex); static String toLowerHex(long v); static void writeHexLong(char[] data, int pos, long v);  }
@Test public void toLowerHex_minValue() { assertThat(toLowerHex(Long.MAX_VALUE)).isEqualTo("7fffffffffffffff"); }
@Test public void toLowerHex_midValue() { assertThat(toLowerHex(3405691582L)).isEqualTo("00000000cafebabe"); }
@Test public void toLowerHex_fixedLength() { assertThat(toLowerHex(0L)).isEqualTo("0000000000000000"); }