Simple wrapper function which connects to a database system, performs a given function on the database, and closes the database connection.

gistfile1.txt

  /**
   * This method calls the given function.
   * <p>
   * This method can be used to do something within the database without thinking about opening and closing a database connection.
   * <p>
   * First it opens a database connection, if none is open.
   * Then it calls the given function.
   * Finally it closes the database connection, if one is open.
   * <p>
   * If an exception is thrown within the given function, this method re-throws it.
   * <br>
   * If opening or closing the database connection causes an exception, then that exception is thrown, unless
   * the given function has thrown one, then the exception of the given function is re-thrown.
   *
   * @param $function
   * @throws Exception
   * @throws Ambigous <NULL, Exception>
   */
  protected function doInDB( $function )
  {
    /**
     * Stores the exception thrown in the given function,
     * so that it can be re-thrown.
     */
    $exceptionInFunction = NULL;

    try
    {
      $this->connect();

      try
      {
        $function( $this );
      }
      catch ( Exception $x2 )
      {
        $exceptionInFunction = $x2;
      }

      $this->close();
      if ( !is_null( $exceptionInFunction ) )
      {
        throw $exceptionInFunction;
      }
    }
    catch ( Exception $x1 )
    {
    	$this->close();
      if ( is_null( $exceptionInFunction ) )
      {
        throw $x1;
      }
      else
      {
        throw $exceptionInFunction;
      }
    }
  }