3.8« Business objects » and « business rules » modeling

« Business objects » are the « Business Rules » (BR) containers. BRs are a set of short and concise business rules. These rules are represented by operations in « Business Object » (BO) class inheriting from an entity class. Operations may come with an OCL (Object Constraint Language) description.

3.8.1BO modeling and applicable rules

Design items

Class, stands for an entity.

Operation.

Operation parameters and return type.

Applicable stereotypes list and modeling rules

• Ocl_sql

This operation describes a SQL request in OCL.

• Ocl_impl

This operation describes its implementation in OCL.

• formula

This operation describes its implementation in Java or .NET.

• setter

This operation is used to change an object or a data type value.

• getter

This operation is used to get back an object or a data type value.

• attach

Used to add an element to a list (association). The method has only one parameter of « List » or « business object » type. The return type must be void.

• detach

Used to remove an element from a list (association). The method has only one parameter of « List » or « business object » type. The return type must be void.

OCL use for business rules modeling

The OCL may be used to interact on various levels. « Business Rules » may also be used to define SQL specific requests.

OCL constraints list

Body, definition of a condition body executed in the BR.

Rules

• A « business object » must inherit from an entity.
• Every operation must be stereotyped.
• Every operation has a return type.
• A « setter » stereotyped method must have only one parameter, a « void » return type, and its name must start with ‘set’ followed by an uppercase letter.
• A « getter » stereotyped method shall not have any parameters, shall not have a « void » return, and its name must start with ‘get’ followed by an uppercase letter.
• A business object name must be the same as the entity it inherits from followed by the ‘BO’ suffix.
• A business object may only inherit from one entity at a time.

NULL parameter

The check_null stereotype is used to tell the application to automatically check whether a method parameter is null. If the concerned parameter is null, an ApplicationException is thrown. The Message exception can be specified into the « message » attribute.

Examples

• Ocl_sql

This operation describes a SQL request in OCL.

Figure 1 «ocl sql» Applied Stereotype example

Figure 2 «ocl sql» Constraint example

• Ocl_impl

This operation describes its implementation in OCL.

Figure 3 «ocl impl» Applied Stereotype example

Figure 4 «ocl impl» Constraint example

• formula

This operation describes its implementation in Java or .NET.

Figure 5 « formula » Tag example

• setter

This operation is used to change an object or a data type value.

Figure 6 «setter» Applied Stereotype example

• getter

This operation is used to return an object or a data type value.

Figure 7 «getter» Applied Stereotype example

• attach

Used to add an element to a list (association). The method must have only one parameter of « List » or « business object » type. The return type must be void.

Figure 8 «attach» Applied Stereotype example

• detach

Used to remove an element from a list (association). The method must have only one parameter of « List » or « business object » type. The return type must be void.

Figure 9 «detach» Applied Stereotype example

• checkNull

Throws an exception if the associated parameter is null

Figure 10 «check_null» Tag example