data-transfer-objects

One area of question for me about DTOs/BOs is about when to pass/return the DTOs and when to pass/return the BOs. My gut reaction tells me to always map NHibernate to the DTOs, not BOs, and always pass/return the DTOs. Then whenever I needed to perform business logic, I would convert my DTO into a BO. The way I would do this is that my BO would have a have a constructor that takes a parameter that is the type of my interface (that defines the required fields/properties) that both my DTO and BO implement as the only argument. Then I would be able to create my BO by passing it the DTO in the

I am using this cookbook recipe to add a data transformer in Symfon 2.1, but I am getting the following error, The option "em" does not exist. Known options are: "attr", "block_name",.... Is this still a valid way to send the entity manager over to the form type? $taskForm = $this->createForm(new TaskType(), $task, array( 'em' => $this->getDoctrine()->getEntityManager(), )); While I can't comment if that's the best way or not, I've always passed them to my task constructor as a hard dependency... Services services: my_bundle.form.type.task: class: Company\MyBundle\Form\Type\TaskType arguments:

I know DTO is a data transfer object and a BO is a business object. But, what does it actually mean? When should I choose one over the other? From, what I understand DTO is just used to transfer data and doesn't have business logic. Does this mean that a DTO doesn't have any method only properties(getter and setter)? But, it still has properties of a BO. Can someone please explain? Thanks. DTO is used to transfer data between layers/tiers. For such purpose it doesn't need any methos and sometimes it even should not have any methods - for example when DTO is exposed over web service. Business

I've been looking at a lot of WCF examples using EntityFramework and most of them seem to return some kind of POCO or DTO class to the client. I was wondering why this was since the default EntityObject includes the [DataContract] attributes and implements INotifyPropertyChanged . Is returning a DTO or POCO class better than an EntityObject (or vise versa)? And is there specific instances where it is better to use one return value over another? As a best practice, you should definitely have it return a DTO/POCO class that is explicitly designed as a data contract and has no persistence logic.

I am trying to implement user space usb driver using libusb1.0.9. I have lpc2148 blueboard(ARM7) with me..This board is loaded with opensource USB stack/firmware by Mr. Bertrik Sikken. Now my user space driver is trying read write with board. I am getting garbage data. I want to know about the flow of bulk tranfer. For any transfer/transaction is there kernel device driver involved?? and do we need usb gadget device driver also?? I am not able to understand that where the data gets copied. Important thing is that when I read/write interrupt gets generated and I can see correct data on LCD. Do