BitcoinUtil { public static String convertByteArrayToHexString(byte[] byteArray) { return DatatypeConverter.printHexBinary(byteArray); } private  BitcoinUtil(); static long convertSignedIntToUnsigned(int signedInt); static byte[] convertIntToByteArray(int intToConvert); static byte[] convertLongToByteArray(long longToConvert); static byte[] convertBigIntegerToByteArray(BigInteger bigIntegerToConvert,int exactArraySize); static byte[] convertVarIntByteBufferToByteArray(ByteBuffer byteBuffer); static long convertVarIntByteBufferToLong(ByteBuffer byteBuffer); static BigInteger getVarIntBI(byte[] varInt); static long getVarInt(byte[] varInt); static byte getVarIntSize(byte firstByteVarInt); static long getSize(byte[] byteSize); static byte[] reverseByteArray(byte[] inputByteArray); static byte[] convertHexStringToByteArray(String hexString); static String convertByteArrayToHexString(byte[] byteArray); static Date convertIntToDate(int dateInt); static boolean compareMagics(byte[] magic1,byte[] magic2); static byte[] getTransactionHash(BitcoinTransaction transaction); static byte[] getTransactionHashSegwit(BitcoinTransaction transaction);  }
@Test public void convertByteArrayToHexString() { byte[] hexByteArray = new byte[]{0x01,(byte)0xFF,0x02}; String resultString = BitcoinUtil.convertByteArrayToHexString(hexByteArray); String expectedString = "01FF02"; assertEquals( expectedString, resultString,"Byte array {0x01,0xFF,0x02} is equivalent to Hex String \""+expectedString+"\""); }