Checkout Flow in WCS- Step 2

Introduction
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Modifying the orderitem qty, selecting the shipping mode, deleting an existing cart-item are few of the instances which lead to invocation of the orderItemUpdateCmdImpl.
 
OrderItemUpdateCmdImpl again extends the OrderItemBaseCmdImpl command which contains the logic for update to the cart , commands called in the sequence-

1)DoInventoryActionCmd(Reserve Inventory)

2)AddOrderItemComponentsCmd

3)ResolveOrderItemPriceCmd

4)UpdateShippingAddressCmd

5)--ValidateTradingPaymentCmd

6)DoInventoryActionCmd(Check Inventory)

7)updateShipInfoCmdImpl

8)RaiseOrderEventCmdImpl

9)OrderCalculateCmd

10)ExtendedOrderItemProcessCmd

For all the updated items:

• ResolveOrderItemPriceCmd command is called to calculate the best suitable price and to update order total.
• doPrice parameter can be passed to ResolveOrderItemPriceCmd command to control whether the order items can skip pricing again
• UpdateShippingAddressCmd command is called to update shipping address
• Update shipping mode
• --ValidateTradingPaymentCmd coomand is called to validate the payment method is compatible with the trading agreement
• If doInventory = Y then DoInventoryActionCmd command is called to update the fulfillment centers and check for available inventory
• UpdateShipInfoCmd command is called to update the shipping instructions, shipping account number and shipping charge type
• RaiseOrderEventCmd command is called to raise ORDERITEM_CREATION_EVENT or ORDERITEM_UPDATE_EVENT
• If the flag calculateOrder is set:
• Call OrderCalculateCmd to do calculations based on the calUsageIds passed in
• ExtendOrderItemProcessCmd is called to execute any customization logic added