public static String toHexStringWithPrefix(BigInteger value) {
        return HEX_PREFIX + value.toString(16);
    }
@Test
    public void testToHexStringWithPrefix() {
        assertEquals(Numeric.toHexStringWithPrefix(BigInteger.TEN), ("0xa"));
        assertEquals(Numeric.toHexStringWithPrefix(BigInteger.valueOf(1024)), ("0x400"));
        assertEquals(Numeric.toHexStringWithPrefix(BigInteger.valueOf(65)), ("0x41"));
        assertEquals(Numeric.toHexStringWithPrefix(BigInteger.valueOf(0)), ("0x0"));
    }