code: public ByteBuffer getValue(int index) throws IOException {
          if (index >= structure.valueSizes.size()) {
              throw new IOException("Index " + index + " is out of range.");
          }
          int length = structure.valueSizes.get(index);
          return ByteBuffer.wrap(value, structure.valueByteOffsets.get(index), length).asReadOnlyBuffer();
      }
docs: Returns the value belonging to the given field as read-only ByteBuffer
  
  @param index
  the index of the requested field
  @return the requested value
  @throws IOException