code: public static String hashSHA256asStringHex(String input, int salt) throws NoSuchAlgorithmException {
  		byte[] in = input.getBytes();
  		ByteBuffer bb = ByteBuffer.allocate(Integer.SIZE + in.length);
  		bb.putInt(salt);
  		bb.put(input.getBytes());
  		byte[] output = Hash.hashSHA256(bb.array());
  		StringBuilder sb = new StringBuilder("0x");
  		 for (byte b : output) {
  		    sb.append(hexDigit[(b >> 4) & 0x0f]);
  		    sb.append(hexDigit[b & 0x0f]);
  		 }
  		 return sb.toString();
  	}
docs: Convenience Function: Hash from String to String Hex representation
  
  @param input
  @return
  @throws NoSuchAlgorithmException