code: public static byte[] combine(final Collection<byte[]> arrays) {
          int length = 0;
          for (final byte[] array : arrays) {
              length += array.length;
          }
          final byte[] joinedArray = new byte[length];
          
          int position = 0;
          for (final byte[] array : arrays) {
              System.arraycopy(array, 0, joinedArray, position, array.length);
              position += array.length;
          }
          return joinedArray;
      }
docs: Combines the specified arrays into a single array.
  
  @param arrays The arrays to combine.
  @return The combined arrays.