When an order is saved in the database or the status of an order is changed (i.e. through the callback of a payment gateway), KonaKart instantiates a class defined by the property ORDER_INTEGRATION_CLASS. If this property isn't set, the class that is instantiated is com.konakart.bl.OrderIntegrationMgr. If you write a custom class it must implement the interface com.konakart.bl.OrderIntegrationMgrInterface which contains some methods:

    /**
     * Called just after an order has been saved. The order details are passed to the method so that
     * all the information should be available in order to integrate with external systems.
     * 
     * @param order
     */
    public void saveOrder(OrderIf order);

    /**
     * Called just before an order has been saved. This method gives the opportunity to modify any
     * detail of the order before it is saved. If null is returned, then no action is taken. If a
     * non null Order is returned, then this is the order that will be saved.
     * 
     * @param order
     * @return Returns an order object which will be saved
     */
    public OrderIf beforeSaveOrder(OrderIf order);

    /**
     * Called just after an order status change
     * 
     * @param orderId
     * @param currentStatus
     * @param newStatus
     */
    public void changeOrderStatus(int orderId, int currentStatus, int newStatus);

    /**
     * This method allows you to introduce a proprietary algorithm for creating the order number for
     * an order just before the order is saved. It is called by the saveOrder() method.
     * The value returned by this method populates the orderNumber attribute of the
     * order when it is saved.
     * If a null value is returned, then the order number of the order is left unchanged.
     * If an exception is thrown, the exception will be also thrown by the saveOrder() method and
     * the order will not be saved.
     * 
     * @param order
     * @return Return the order number for the new order
     * @throws Exception
     */
    public String createOrderNumber(OrderIf order) throws Exception;

    /**
     * This method allows you to generate a tracking number for an order just before the order is
     * saved. It is called by the saveOrder() method. The value returned by this method
     * populates the trackingNumber attribute of the order when it is saved.
     * If a null value is returned, then the tracking number of the order is left unchanged.
     * If an exception is thrown, the exception will be also thrown by the saveOrder() method and
     * the order will not be saved.
     * 
     * @param order
     * @return Return the tracking number for the new order
     * @throws Exception
     */
    public String createTrackingNumber(OrderIf order) throws Exception;

    /**
     * Called just before a subscription is inserted. This method gives the opportunity to modify
     * any detail of the subscription before it is inserted. If null is returned, then no action is
     * taken. If a non null subscription is returned, then this is the subscription that will be
     * saved.
     * 
     * @param subscription
     * @return Returns a Subscription
     * @throws Exception 
     */
    public SubscriptionIf beforeInsertSubscription(SubscriptionIf subscription) throws Exception;

    and more........

The state of an order may be changed manually through the Admin App. In this case KonaKart instantiates a class defined by the property ADMIN_ORDER_INTEGRATION_CLASS. If this property isn't set, the class that is instantiated is com.konakartadmin.bl.AdminOrderIntegrationMgr. If you write a custom class it must implement the interface com.konakartadmin.bl.AdminOrderIntegrationMgrInterface which contains the method:

    /**
     * Called just after an order status change
     * 
     * @param orderId
     *            Id of the order
     * @param currentStatus
     *            Current state of the order
     * @param newStatus
     *            New state of the order
     */
    public void changeOrderStatus(int orderId, int currentStatus, int newStatus);

    /**
     * This method may be customized in order to implement an algorithm that creates an RMA code for
     * the order. The Administration Application will use the returned value (if not null) to
     * automatically populate the RMA code entry field.
     * 
     * @param orderId
     *            Id of the order
     * @return Returns an RMA Code
     */
    public String getRMACode(int orderId);
    

This mechanism is a useful generic way to interface KonaKart to external systems since the custom classes could write data to a database, call a web service or write data to a file etc.

The ORDER_INTEGRATION_CLASS and ADMIN_ORDER_INTEGRATION_CLASS properties can be edited in the Configuration>>Stock and Orders section of the Admin App.