Application Services
Definition
A compound object used to moderate communication of entity and external services with the user interface in the CAF Core architecture.
Use
You use application services to store the business logic of your project model. It is the most flexible of all services in that you can define the transactional behavior of the service and its usability in other applications.
You can use other entity and external services and their corresponding operations, input and output parameters and exception to map your model. As a result, you maintain the flexibility of being able to code for your specific application needs.
With application services, you can automatically provide enhanced infrastructure services like authorization, tracing, and transactional handling based on metadata information from the CAF service layer.
Structure
Application services represent the business logic and connect to the UI entity service world. Your main task is to map these services via different service operation types.
Operations
By using operation parameters from other services, you can enable CAF to generate the general scope for coding. You then have the option to specify the business process logic through specific Java coding.
You can use the following operation types:
● Custom
● Create
● Read
● Update
● Delete
● FindBy
These operations assist you, for example, in forwarding data from the UI to the entity service or vice versa. As a result, you see mainly coding which contains the mapping parameters of the entity and external services to the UI.
However, you can also create your own operations to create coding to execute different transformation or checks. By modeling operations, you can automatically generate code describing, for example, the number of arguments or operation return type. This is not possible with entity services.
For more information, see:
● Classification Application Service Operations for operations used in classification assignments.
● Service Operations for general information on the type of operations used in CAF Core.
● Service Mapping for a procedure and guidelines describing how to map parameters.
Core Services
In the table below, you can see a list of services you can use to model application services.
Name |
Description |
ClassificationApplicationService |
This service calls the entity service CategoryService and is used to create file structures. It makes a distinction between files and folders, therefore categories can be assigned to the entity service type and folders can be assigned to instances. As a result, you can filter objects, for example, in SAP NetWeaver BI. For more information, see Classification Application Service Operations. |
CurrencyConversion |
This service is used to execute currency conversions. It can only be used internally. |
DocContent |
You use this service to select a document, which is then stored in SAP KM. This service is used to load the document, whereas header information from the document is carried out with the entity service Document. |
UnitConversion |
You use this service to convert units of measurement, for example from centimeters to inches. It can only be used internally. |
Fore more information about the additional service types available in CAF, see Getting Involved → Working with Composite Application Services → Composite Application Services and Data Types.
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