Ejemplo n.º 1
0
  /**
   * Method to apply any restrictions to the created ResultSet.
   *
   * @param ps The PreparedStatement
   * @param query The query
   * @param applyTimeout Whether to apply the query timeout (if any) direct to the PreparedStatement
   * @throws SQLException Thrown when an error occurs applying the constraints
   */
  public static void prepareStatementForExecution(
      PreparedStatement ps, Query query, boolean applyTimeout) throws SQLException {
    NucleusContext nucleusCtx = query.getExecutionContext().getNucleusContext();
    RDBMSStoreManager storeMgr = (RDBMSStoreManager) query.getStoreManager();
    PersistenceConfiguration conf = nucleusCtx.getPersistenceConfiguration();

    if (applyTimeout) {
      Integer timeout = query.getDatastoreReadTimeoutMillis();
      if (timeout != null && timeout > 0) {
        ps.setQueryTimeout(timeout / 1000);
      }
    }

    // Apply any fetch size
    int fetchSize = 0;
    if (query.getFetchPlan().getFetchSize() > 0) {
      // FetchPlan has a size set so use that
      fetchSize = query.getFetchPlan().getFetchSize();
    }
    if (storeMgr.getDatastoreAdapter().supportsQueryFetchSize(fetchSize)) {
      ps.setFetchSize(fetchSize);
    }

    // Apply any fetch direction
    String fetchDir =
        conf.getStringProperty(RDBMSPropertyNames.PROPERTY_RDBMS_QUERY_FETCH_DIRECTION);
    Object fetchDirExt =
        query.getExtension(RDBMSPropertyNames.PROPERTY_RDBMS_QUERY_FETCH_DIRECTION);
    if (fetchDirExt != null) {
      fetchDir = (String) fetchDirExt;
      if (!fetchDir.equals("forward")
          && !fetchDir.equals("reverse")
          && !fetchDir.equals("unknown")) {
        throw new NucleusUserException(LOCALISER.msg("052512"));
      }
    }

    if (fetchDir.equals("reverse")) {
      ps.setFetchDirection(ResultSet.FETCH_REVERSE);
    } else if (fetchDir.equals("unknown")) {
      ps.setFetchDirection(ResultSet.FETCH_UNKNOWN);
    }

    // Add a limit on the number of rows to include the maximum we may need
    long toExclNo = query.getRangeToExcl();
    if (toExclNo != 0 && toExclNo != Long.MAX_VALUE) {
      if (toExclNo > Integer.MAX_VALUE) {
        // setMaxRows takes an int as input so limit to the correct range
        ps.setMaxRows(Integer.MAX_VALUE);
      } else {
        ps.setMaxRows((int) toExclNo);
      }
    }
  }