Different Programming Methodologies

[jimin-kiim]

• Unstructured Programming(1960)
• Procedural Programming(1970)
• Modular Programming(Structured Programming)
• Object Oriented Programming

[jimin-kiim]

Unstructured Programming

• consists of only one main program
  • all data are global data
• there's no function and program is the sequence of commands and statements indeed
  • goto statement is used

=> complex, tangled structure. => hard to understand and follow the codes => difficult to modify => costs heavily in the maintenance phase

[jimin-kiim]

Procedural Programming

• consists of a main program and the procedures
  • main program coordinates calls to the procedures and hands over appropriate data as parameters to them
  • functional decomposition
  • reduce repetition and more error-free than unstructured programming
  • top-down approach
  • divide and conquer method

[jimin-kiim]

Modular Programming

• consists of a main program and the modules
  • main program coordinates calls to the modules and hands over appropriate data as parameters to them

Module

• a group of procedures of a common functionality
• used through the interfaces
  • implementation is hidden
  • data are localized inside the modules ( if the data are used globally, if makes the modules dependent one another -> complex, hard to maintain )
• developed and understood independently

-> can improve maintainability

[jimin-kiim]

traditional structured programming methodologies are not sufficient for large software maintenance and reuse

OOP

• consists of objects
• a set of interacting objects
• doesn't consider the problem domain as just a flow of processings
• define objects related to the problem domain and regards these objects communicate information each other (through message passing)
  • structured programming treats data and operations independently even though they are related

    Object

  • a component of software
  • combination of data and operations
  • identity + attribute + behavior(method) + relationships with other objects
  • send message to each other ( interact, communicate information each other ) calling a method
  • an instance of a class

💡 good for developing large software

• increase
  • reusability
  • maintainability
  • understandability
  • productivity of programmer
  • quality of software