code: public BookInfo[] getAvailableBooks()
              throws BitsoAPIException, BitsoPayloadException, BitsoServerException {
          String request = "/api/v3/available_books";
  
          String getResponse = sendGet(request);
          JSONArray payloadJSON = (JSONArray) getJSONPayload(getResponse);
          int totalElements = payloadJSON.length();
          BookInfo[] books = new BookInfo[totalElements];
          for (int i = 0; i < totalElements; i++) {
              books[i] = new BookInfo(payloadJSON.getJSONObject(i));
          }
          return books;
      }
docs: Public Functions