1. Understanding Computers Ch. 131 Chapter 13 Program Development and Programming Languages

2. Understanding Computers Ch. 132 Overview This chapter covers: The program development life cycle (PDLC) Tools that can facilitate program development Programming languages

3. Understanding Computers Ch. 133 The Program Development Life Cycle (PDLC)

4. Understanding Computers Ch. 134 Problem Analysis Purpose: Review the specifications developed during system design and develop program specifications. Usually performed by systems analyst and programmer. Documentation: Program specifications (what is does, timetable, programming language to be used, etc.)

5. Understanding Computers Ch. 135 Program Design Purpose: To determine the algorithms to be used with the final program. Approaches to program design: Structured programming Structures the program Object-oriented programming (OOP) Groups program components Aspect-oriented programming (AOP) Re-uses program components

6. Understanding Computers Ch. 136 Program design tools: Structure charts Program flowcharts Pseudocode Data modeling Program Design, Cont’d.

9. Understanding Computers Ch. 139 Program Design, Cont’d. Control structures — patterns that control when and how the instructions in a computer program are performed. Sequence Selection (if-then-else, case) Repetition (do-while, do-until)

11. Understanding Computers Ch. 1311 Program Design, Cont’d. Good program design Be specific. One-entry-point, one-exit-point rule. No infinite loops or logic errors. Documentation: Design specifications (expressed using flowcharts, pseudocode, structure charts, data models, etc.).

13. Understanding Computers Ch. 1313 Program Coding Coding — the process of writing the actual programming steps using a programming language. Factors involved when choosing a programming language: Suitability Integration Standards Programmer availability Portability Development speed

14. Understanding Computers Ch. 1314 Program Coding, Cont’d. Coding standards — list of rules designed to standardize programming styles.

15. Understanding Computers Ch. 1315 Program Coding, Cont’d. Reusable code Data dictionary Translating coded programs into executable code Compilers Interpreters Assemblers Documentation: Documented, executable source code.

16. Understanding Computers Ch. 1316 Program Debugging and Testing Debugging—the process of making sure a program is free of errors. Preliminary debugging Syntax errors (typos, wrong syntax, etc.). Logic errors (wrong formulas, wrong relational operators, etc.). Dummy print statements can help locate errors.

18. Understanding Computers Ch. 1318 Program Debugging and Testing Testing Alpha testing (inside organization) Beta testing (outside testers) Documentation: Completed program package.

19. Understanding Computers Ch. 1319 Program Maintenance Program maintenance—the process of updating software so that it continues to be useful. Software updates Software revisions Made easier by good coding standards, data dictionaries, reusable code, etc. Documentation: Amended program package.

20. Understanding Computers Ch. 1320 Tools for Facilitating Program Development Application generators: Macro recorders Report and form generators Code generators Computer-aided software engineering (CASE) Software-asset management tools Rapid application development (RAD)

21. Understanding Computers Ch. 1321 Programming Languages Programming language—a set of rules used to write instructions to the computer. Categories of programming languages: Low-level languages (machine and assembly language). High-level languages (BASIC, COBOL, C++, etc.). Very-high-level (fourth-generation languages). Natural and visual languages.

22. Understanding Computers Ch. 1322 Popular Programming Languages FORTRAN—the oldest high-level programming language; designed for scientific and mathematical applications.

23. Understanding Computers Ch. 1323 Popular Programming Languages, Cont’d. COBOL—designed for business transaction processing.

24. Understanding Computers Ch. 1324 Popular Programming Languages, Cont’d. Pascal—designed to teach structured programming; useful for math and science applications.

25. Understanding Computers Ch. 1325 Popular Programming Languages, Cont’d. BASIC—an easy-to-learn beginner’s programming language. Visual Basic— an object-oriented, fourth-generation version of BASIC.

26. Understanding Computers Ch. 1326 Popular Programming Languages, Cont’d. C, C++, C#—versions of the highly efficient C programming language; C++ and C# are object- oriented.

27. Understanding Computers Ch. 1327 Popular Programming Languages, Cont’d. Java—object-oriented programming language commonly used for Web applications. Platform independence—Java programs can run on any platform that supports the Java Virtual Machine. Java applets—concise stand-alone Java applications ready to be inserted into Web pages. Class files Parameters

29. Understanding Computers Ch. 1329 Popular Programming Languages, Cont’d. Other high-level languages: Ada APL LISP Logo PL/1 Prolog RPG SmallTalk

30. Understanding Computers Ch. 1330 Summary The program development life cycle (PDLC) Good program design Basic control structures Coding, debugging, maintaining, and documenting programs Tools that facilitate the program development process Common programming languages