code: void abort() throws SQLException {
          if (mRegisteredLobs != null) {
              for (JDBCLob lob : mRegisteredLobs) {
                  lob.close();
              }
              mRegisteredLobs = null;
          }
  
          if (mIsNested) {
              if (mReady) {
                  if (mSavepoint != null) {
                      mConnection.rollback(mSavepoint);
                      mSavepoint = null;
                  }
                  mReady = false;
              }
  
              if (mOriginalLevel != LEVEL_NOT_CHANGED) {
                  if (mOriginalLevel == Connection.TRANSACTION_NONE) {
                      mConnection.setAutoCommit(true);
                  } else {
                      mConnection.setTransactionIsolation(mOriginalLevel);
                  }
              }
  
          } else {
              if (mReady) {
                  mConnection.rollback();
                  mReady = false;
              }
          }
      }
docs: Note: The caller should close the connection after aborting if
  shouldCloseConnection() returns true.