How do object oriented design and structure design differ?

Answer 1

Object Oriented programming is a superset of structured programming. Structured programming is as follows:

--Program start

var

var

var

function { ... }

function { ... }

function { ... }

main { ... }

--- Program End

You have units of code, which operate on variables, and are called in reference to those variables, to follow a structure acting on those variables.

Object oriented is as follows:

--- Program Start

object {

var

var

function { ... }

function { ... }

function { ... }

}

var

var

function { ... }

main { ... }

--- Program end

Variables can be objects, which have their own data and functions. Think like C and structures, except structures can have functions "in them" which operate specificly on their own data. Thus, instead of referencing a function (a block of code) and telling it to operate on a variableq you reference an object and tell it to perform an operation, most often on itself, specific to itself, using its own data. Instead of creating units of data to pass to functions which operate on them, you create objects and have them perform operations [on themselves].

Functions attached to objects don't need a specific name; rather than task_struct_sort_children(task) and acl_rules_struct_sort_children(task), you can have task and acl_rules with task->sort_children() and acl_rules->sort_children(), which have completely different specific function but the same logical function, and operate on the specific instance of the object.

structured oriented programming and object oriented programming have some features of similarities, but the distinction between the two is that the former relies to the GOTO statements thus the developer has a tendency to confuse while the latter is subgrouped from objects, classes, methods and hierarchies.

Answer 2

Structured programming tells the program what to do, step by step. For example:

Receive two numbers from input;

add them;

output them;

Object oriented programming creates several objects (like a button on the screen, a file, or a text box, etc..) that have properties, events and methods. Properties are values that the object can have. For example, the width, height, and the caption of the button would all be properties of a button.

An event is something that happens to an object, like being clicked, moved, or having text entered into it. A method is like a function, it is something that the object does when a certain event happens to it. For example, when a button is clicked, it executes a method which will change the text in a text box. This is an example of an event triggering a method that will change the text box's properties.

Instead of having a list of instructions, like structured programming, object oriented programming begins the program by waiting for an event to happen. This event can be a mouse click, the user scrolling down, or even the On Load event, which happens right when the program starts. When an event happens, the program will execute the method that corresponds to the event, and then will wait for more events to happen, until the program is ended. For example, when you load Microsoft Word, it will not do anything until you type in text or press a button. It will just wait for an event to happen. Object oriented programming is useful when you cannot predict what the user will do, or in what order. Instead of assuming that the user will trigger this event, and then will trigger that event, you can make use object oriented programming to make a program that will be ready for whatever the user does.

Answer 3

Object oriented software development methodlogy is not as complex as structure development. It is very easy to debug the object oriented code as comparative.Object oriented methodology focuses on the representing the problem using several real world object and their behaviour. BUt structured programming uses the program in a logical structured in hierarchy ( top to buttom process). It is reliable to use the object oriented methodology because it can be maintain ,resuse and extend as comparative to that of structured programmng.

Object oriented methodology uses several concepts such as encapsulation, inheritance , polymorphsm and message passing but structured used sequence selection and iteration.

so.it is better to use OOSD method to develop any software rather than SSD (structure software development ) to reduce the complexity.

Thank you ..

Answer 4

Structured Analysis

In Structured Analysis, the focus is only on process and procedures.

Modeling techniques used in it are DFD(Data Flow Diagram), Flowcharts etc.

This approach is old and is not preferred

Object Oriented AnalysisWhereas in Object Oriented Analysis, the focus is more on capturing the real world objects in the current scenario that are of importance to the system. [2] It stresses more on data structure and less on procedural structure. Without actually identifying objects, what are you going to interact with, and whose state will you change. In this approach, objects are identified, their relationships among each other, possible states that each object can be in, and finally how all objects collaborate with each other to achieve a broader system goal are identified.

Modeling techniques used in it are UML(Unified modeling Language), that can present both structural and behavioural/procedural aspect of the system. UML includes Class Diagram, State Diagram, Use case diagram, Sequence Diagram, etc.

Using this approach keeps your system more maintainable and reusable, and is a common choice nowadays

by msmzathir@gmail.com

Answer 5

• structured design is an older technique that organizes the program as an upside down tree of subroutines. subroutines at each level call subroutines at lower levels to perform their function. the subroutines at the lowest level have such simple functions to do they do it internally without calling other subroutines. the single subroutine at the top coordinated the operation of the whole program.
• object oriented design is a newer technique that organizes the program around independent intercommunicating objects. These objects are effectively individual programs themselves, often performing some major sub-function of the system. they intercommunicate by calling subroutines in each other (usually called methods). traditional object oriented programming coding standards completely forbid the use of global variables, allowing variables to only be global in the scope of one object.

Answer 6

they are not both used at the same time...

Answer 7

Process Oriented : Program is organised around methods.

Object Oriented : Program is organised around data.