A business object is an entity within a multi-tiered software application that works in conjunction with the data access and business logic layers to transport data.[citation needed]
Business objects separate state from behaviour because they are communicated across the tiers in a multi-tiered system, while the real work of the application is done in the business tier and does not move across the tiers.
Function
[edit]Whereas a program may implement classes, which typically end in objects managing or executing behaviours, a business object usually does nothing itself but holds a set of instance variables or properties, also known as attributes, and associations with other business objects, weaving a map of objects representing the business relationships.
A domain model where business objects do not have behaviour is called an anemic domain model.
Examples
[edit]For example, a "Manager" would be a business object where its attributes can be "Name", "Second name", "Age", "Area", "Country" and it could hold a 1-n association with its employees (a collection of "Employee" instances).
Another example would be a concept like "Process" having "Identifier", "Name", "Start date", "End date" and "Kind" attributes and holding an association with the "Employee" (the responsible) that started it.
See also
[edit]- Active record pattern, design pattern that stores object data in memory in relational databases, with functions to insert, update, and delete records
- Business intelligence, a field within information technology that provides decision support and business-critical information based on data
- Data access object, design pattern that provides an interface to a type of database or other persistent mechanism, and offers data operations to application calls without exposing database details
- Data transfer object, design pattern where an object carries aggregated data between processes to reduce the number of calls
References
[edit]- Rockford Lhotka, Visual Basic 6.0 Business Objects, ISBN 1-86100-107-X
- Rockford Lhotka, Expert C# Business Objects, ISBN 1-59059-344-8
- Rockford Lhotka, Expert One-on-One Visual Basic .NET Business Objects, ISBN 1-59059-145-3
External links
[edit]- A definition of domain model by Martin Fowler
- Anemic Domain Model by Martin Fowler