Software Development Approaches Structured Approach Formal Stages of

Software Development Approaches Structured Approach

Formal Stages of the Structured Approach • • • Define the problem Plan the solution Build the solution Check the solution Modify the solution

Software Life Cycle Modify the solution Define the problem Plan the solution Check the solution Build the solution Marrickville High School 3

Waterfall Model Define the problem Plan the solution Each stage “flows” on to the next stage Build the solution Check the solution Modify the solution

Defining the Problem • Systems analyst and management • The problem must be fully understood before a solution can be developed • Identification of inputs, outputs and processes • A requirements definition is developed

Planning the Solution (1) • Identification of a suitable development approach • Design of appropriate algorithms • Modularisation • Determination of appropriate data structures • Design of test data and expected output

Planning the Solution (2) • Desk check of the algorithms • Identification of existing code that can be used

Building the Solution • Coding of the solution in an appropriate language • Testing of the solution using test data • • • Documentation of the solution, including Algorithms Tutorials Test data and expected output Data dictionary

Checking the Solution • Testing the completed solution using test data • Testing performance under real conditions • Users test the solution & identify problems • Evaluation of the completed solution • Compared with the original requirements definition

Modifying the Solution • All software products have a life span. They need to be upgraded to: • Include new functionality • Improve existing functionality • Maintenance programmers perform upgrades • Changes must be fully documented