Metacat

  public static synchronized int getFreeDBConnectionNumber()

  /**

   * Method to decrease dbconnection pool size when all dbconnections are idle

   * If all connections are free and connection pool size greater than 

   * initial value, shrink connection pool size to intital value

   */

  public static synchronized void shrinkDBConnectionPoolSize()

  {

     int connectionPoolSize = 0; //store the number of dbconnection pool size

     int freeConnectionSize = 0; //store the number of free dbconnection in pool

     int difference = 0; // store the difference number between connection size

                         // and free connection

     DBConnection conn = null;

     connectionPoolSize = connectionPool.size();

     freeConnectionSize = getFreeDBConnectionNumber();

     MetaCatUtil.debugMessage("Connection pool size: " +connectionPoolSize, 20);

     MetaCatUtil.debugMessage("Free Connection number: "+freeConnectionSize,20);

     difference = connectionPoolSize - freeConnectionSize;

     //If all connections are free and connection pool size greater than 

     //initial value, shrink connection pool size to intital value

     if (difference == 0 && connectionPoolSize > INITIALCONNECTIONNUMBER)

     {

       //db connection having index from intialConnectionnumber - 1 to

       //connectionpoolsize -1 should be close and remove from pool

       for ( int i=INITIALCONNECTIONNUMBER -1; i<connectionPoolSize; i++)

       {

         //get the dbconnection from pool

         conn = (DBConnection) connectionPool.elementAt(i);

         //close conn

         try

         {

           conn.close();

         }//try

         catch (SQLException e)

         {

           MetaCatUtil.debugMessage("Couldn't close the DBConnection in" +

                         " DBConnectionPool.shrinkDBConnectionPoolSize: " +

                         e.getMessage(), 30);

         }//catch

         //remove it from pool

         connectionPool.remove(i);

       }//for

     }//if

  }//shrinkDBConnectionPoolSize