2.3 Robust Programs

2.3 Robust Programs

1. Defensive Design

   • Anticipation of program misuse
   • Ensure code is well-maintained
   • Reduce number of errors in code via testing
   • Testing Authentication- Confirmation of identity and increasing security
   • Contingencies are planned for
   • Input Sanitisation is removing unwanted characters before passing data through program
   • Input Validation is checking if data meets certain criteria before being passed into program
   • Protecting programs

2. Maintainability

   • Allows other programmers to understand the code's function
   • Comments- explain key features of program
   • Indentation to make program flow more visible

3. Errors

   • Syntax Errors are made when the compiler/interpreter doesn't understand data due to it not following the rules/grammar of programming language
   • Logic Errors are made when the compiler/interpreter runs but the program makes an unexpected error

4. Iterative Testing

   • Program will go through development multiple times in order to match the customer's wants. First cycle may only include main features whereas new cycle has adjustments to requirements.

5. Final testing

   • Program only goes through development cycle once.
   • All required features added at same time and is tested for initial requirements of customer
   • Customer will get what they asked for but not always what they want

6. Test Plan

   • Normal data is data the user is likely to input
   • Extreme data includes values at the limit of what the program should be able to handle
   • Erroneous data are inputs the program should never accept