Class SQLConnectionManager

Method Details

• getConnection

  public static Connection getConnection() throws SQLException

  Gets a new connection to the default database given in the SmartClient configuration file. The server.properties configuration file is located in the isomorphicConfig directory of the SmartClient installation, and contains the connection parameters for the database given by the sql.defaultDatabase property.

  This method returns a fresh connection to the database - either borrowed from the pool if connection pooling is switched on, or a completely new connection if pooling is off, or there are no free connections in the pool. The connection returned is not the same connection as that used to implement auto-managed transactions (see DSRequest.shouldJoinTransaction()), which leads to two considerations

  • Connections obtained by this method are not managed by framework code, so your application code must call free(Connection) to return the connection. Failure to do so will result in a connection leak
  • If you use a connection obtained by this method in the middle of a transactional update bear in mind that it will not have visibility of rows inserted or changed on the transactional connection. Also, be careful not to introduce deadlocks if running updates on a separate connection in the middle of a transactional update, especially if the same tables are involved

  If you instead want access to the database connection used by the framework for automatically managed transactions, see DataSource.getTransactionObject(com.isomorphic.datasource.DSRequest), and also this Showcase example: Transactional User Operations. Note that you should not call free() on the connection returned by this method - it is managed by the framework.

  Returns:

  a java.sql.Connection session with the default database

  Throws:

  SQLException

  See Also:

  • free(Connection conn)

• getConnection

  public static Connection getConnection(String serverName) throws SQLException

  Gets a new connection to the database given in the SmartClient configuration file by the parameter database name. The server.properties configuration file is located in the isomorphicConfig directory of the SmartClient installation, and contains the connection parameters for the database given by name.

  Note that the same caveats apply to this method as apply to the no-parameter version getConnection()

  Parameters:

  serverName - the name of the database as given in the configuration file

  Returns:

  a java.sql.Connection session with the database

  Throws:

  SQLException

  See Also:

  • free(Connection conn)

• free

  public static void free(Connection conn) throws SQLException

  Frees a connection previously obtained via SQLConnectionManager. Note that you are responsible for freeing any connections you borrow from the SQLConnectionManager; if you neglect to do so, you will cause connection leaks.

  Parameters:

  conn - The Connection object to free

  Throws:

  SQLException

  See Also:

  • getConnection()