What are Business Objects and what is Business Logic?

Question

When reading, I keep seeing references to what they call Business Objects. I\'ve looked up on Wikipedia and such but I keep not getting what a Business Ob

Answer 1

In traditional 3 tier programming you have three logical layers or tiers. You have a presentation layer which is the User Interface, the bottom layer would be the database layer. The middle layer would be the business objects layer. As pointed out above the business objects should be abstracted in that the site might not be about business at all. It is a layer of abstraction that makes it easier to make changes to the presentation layer or to switch to a different data source.

If your user interface level has no or very little code behind it. It makes it easier for designers to work with programmers. The designers can change the look and feel of the site without the programmers having to do a substantial rewrite of the code that makes that site work. With the business objects layer you do the heavy listing of the site. You make calls into the database layer without the business object knowing whether your database layer is in XML or relational database. And the business object layer then would update a response to the UI layer. Typically the example used is for a bank transaction. In the user interface a client enters the amount he would like to transfer from his savings account to his checking account.

The business object layer will contain the business rules for the bank . That means it will check the balance of the users savings account and make sure the amount to transfer does not exceed the balance of the account. The business layer will contain the classes that actually calculate the new balances for both the savings account and the checking account and it will alert the database layer to update the database.