Repository Use Cases and CRUD Repository Use Cases

Repository Use Cases and CRUD

Repository Use Cases There are four main operations that are commonly performed on repositories, whether they are files or true databases: Create – create and add an item to the repository Read – view a repository item Update – edit a repository item Delete – remove a repository item These operations are collectively known as CRUD. ¨ ¨ In most applications, there will be at least one CRUD use case. For example, this semester’s project may include a CRUD use case for maintaining the repository of CS, IS, and GEP courses. You may also have other repositories that require maintenance. The following slides show a suggested way in which you can handle CRUD use cases in your SRS. CMSC 345, Version 1/11 2

Suggested Approach for Our Class n n n Have a top-level use called something like Maintain X Repository (e. g. , Maintain Accounts Repository) Write a corresponding specification for this use case. The use case should include viewing the repository as one of the steps in the Main Scenario. Draw a sub-use case diagram for Maintain X Repository that has three extensions for creating an item (e. g. , Create Account) in the X repository, ¨ editing an item in the X repository, and ¨ deleting an item from the X repository. ¨ n For our class, you do not need to have a specification for each of these three extended use cases. (In industry, these might need to be written. ) CMSC 345, Version 1/11 3

Top-level use case diagram with a CRUD use case system name 1 Use Case 1 Name 2 Use Case 2 Name 3 Maintain X Repository role name n Use Case n Name CMSC 345, Version 1/11 external system name CRUD use case 4

CRUD Use Case Specification Number 3 Name Maintain X Repository Summary User adds to, edits, or deletes from X repository Priority 5 Preconditions precondition Postconditions postcondition Primary Actor(s) role name Secondary Actor(s) external system name Trigger User chooses to maintain X repository Main Scenario Step Extensions Open Issues CMSC 345, Version 1/11 Action 1 System displays repository 2 User performs repository operation 3 System updates repository Step Branching Action 2 a Use Case 3 a: Create Y 2 b Use Case 3 b: Edit Y 2 c Use Case 3 c: Delete Y open issue 5

CRUD Sub-Use Case Diagram 3 c Delete Y 3 Maintain X Repository role name 3 b Edit Y 3 a Create Y “Y” is one of the items in the “X” repository CMSC 345, Version 1/11 external system name All dependencies are extend unless stereotyped otherwise. 6