code: private void close(State state) {
          // ensure close happens once only to avoid race conditions
          if (state.closed.compareAndSet(false, true)) {
              Util.closeQuietly(state.ps);
              if (isCommit() || isRollback())
                  Util.closeQuietly(state.con);
              else
                  Util.closeQuietlyIfAutoCommit(state.con);
          }
      }
docs: Cancels a running PreparedStatement, closing it and the current
  Connection but only if auto commit mode.