Case Study

Requirement and analysis disciplines through analysis of a simple case study, and to express the results through the relevant UML diagrams.

Vertical Storage Solutions (VSS) is a supplier of high bay pallet storage systems for warehouses. A high bay system is essentially a large shelving unit for storing pallets in a warehouse (Figure 1). Each set of shelves is separated from the next by a narrow aisle. Electrically operated cranes move along the aisles horizontally and up and down vertically in order to move pallets to shelf locations in the high bay system. Each crane can also move along the end of the shelving system so that it can move from aisle to aisle and to a loading area where pallets can be loaded onto and off the cranes. High bay systems are much higher than conventional pallet racking, which is designed to be accessible to fork-lift trucks. High bay systems often are built two or three storeys below ground level and may be several storeys high. The typical height of a high bay system may be 25 metres.

VSS has an existing software package that controls its high bay systems and wants to rewrite it. The existing system is written in C and uses C-ISAM files to store data.

The supplier of the C-ISAM libraries is discontinuing support, and VSS wants to move its system to a newer platform. The existing storage control system (SCS) interfaces to other warehouse management systems (WMS) through a series of text files that are transferred into a specific directory on the machine that runs the SCS.

VSS want to change this interface so that other WMS can send messages to the SCS using SOAP-based web services.

Tasks

Part A - Use Cases Perform a requirement analysis for the Case Study.

Express the results using the subsequent artefacts: A use case diagram for the functional requirements of the entire system, accompanied by: Short use case descriptions for all use cases. Select the most essential use case in the system, and give a full use case description for it. Produce an activity diagram that expresses the workflow for that use case.

Part B - System-wide and Non-functional Requirements

Give a system-wide (non-functional) requirement document that documents the architectural requirements the system must address.

Part C - Use Case Realization

Prepare a domain model for the Case Study. Express your model with a class diagram, showing any inheritance and compositional relationships. Create a use case realization showing the sequence of messages involved for the use case selected for the full description in Part A.

Express this use case realization in a communication diagrams. Use the GRASP concept of a Controller class to coordinate the use case.

Part D - Analysis Classes

Explain a summary analysis class diagram showing the attributes and methods required by problem domain classes involved in the use case realized in Part C.

Part E - Object Interactions

Create operation specifications for the two most complex methods contained in one of the nominated objects specified for the Case Study.

Part F - Object State

Prepare a state diagram for the object chosen for Part E. Nominated objects will be listed in the Case Study.