content: package com.cf.carpark.service.vzenith.cloud.util;
  
  import java.security.MessageDigest;
  import java.security.NoSuchAlgorithmException;
  import java.util.Base64;
  
  public class BinaryUtil {
    private static final char[] HEX_DIGITS = {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D',
      'E', 'F'};
  
    public static String toBase64String(byte[] binaryData) {
      return new String(Base64.getEncoder().encode(binaryData));
    }
  
    public static byte[] fromBase64String(String base64String) {
      return Base64.getDecoder().decode(base64String);
    }
  
    public static byte[] calculateMd5(byte[] binaryData) {
      MessageDigest messageDigest = null;
      try {
        messageDigest = MessageDigest.getInstance("MD5");
      } catch (NoSuchAlgorithmException e) {
        throw new RuntimeException("MD5 algorithm not found.");
      }
      messageDigest.update(binaryData);
      return messageDigest.digest();
    }
  
    public static String encodeMD5(byte[] binaryData) {
      byte[] md5Bytes = calculateMd5(binaryData);
      int len = md5Bytes.length;
      char buf[] = new char[len * 2];
      for (int i = 0; i < len; i++) {
        buf[i * 2] = HEX_DIGITS[(md5Bytes[i] >>> 4) & 0x0f];
        buf[i * 2 + 1] = HEX_DIGITS[md5Bytes[i] & 0x0f];
      }
      return new String(buf);
    }
  }
  