002_a_pemrograman berorientasi object

8/7/2019 002_A_Pemrograman Berorientasi Object

1/26

Pemrograman Berorientasi

Object

Introduction to class and object

ImanLHakim, 2011


2/26

Objectives

Tujuan Instruksional Khusus (TIK)

Mahasiswa mampu mengerti dan memahami konsep

dasar dari Pemrograman Berorientasi Objek yaitu

Abstraksi, Encapsulasi, Modularity dan Hierarki. Pokok Bahasan

Konseptual Objek Model

Sub Pokok Bahasan Konseptual Objek Model (Abstraksi dan Encapsulasi)

Konseptual Objek Model (Modularitas,Hierarki)


3/26


4/26

Programmings Abstraction

1. Procedure-oriented Algorithms

2. Object-oriented Classes and objects

3. Logic-oriented Goals, often expressed in a predicate

calculus

4. Rule-oriented Ifthen rules

5. Constraint-oriented Invariant relationships


5/26

Four major elements of O-O

Model without any one of these elements is not

object-oriented.

Abstraction

Encapsulation

Modularity

Hierarchy


6/26

Three minor elements of the object

model

Each of these elements is a useful, but not

essential, part of the object model

Typing

Concurrency

Persistence


7/26

Abstraction

Abstraction focuses on the essential

characteristics of some object,

relative to the perspective of the

viewer

Entity abstraction An object that represents a useful

model of a problem domain or

solution domain entity

Action abstraction

An object that provides a

generalized set of

operations, all of which perform the

same

kind of function

Virtual machine

abstraction

An object that groups operations

that are all

used by some superior level ofcontrol, or

operations that all use some junior-

level set

of operations

Coincidental

abstraction

An object that packages a set of

operations

that have no relation to each other


8/26

Encapsulation

Encapsulation hides the

details of the

implementation of an

object

Encapsulation is the process of

compartmentalizing the elements of anabstraction that constitute its structure and

behavior; encapsulation serves to separate the

contractual interface of an abstraction and its

implementation


9/26

Modularity

Modularity packages abstractions into discrete units.

Modularity is the property of a system that has

been decomposed into a set of

cohesive and loosely coupled modules


10/26

Hierarchy

Hierarchy is a ranking or orderingof abstractions.


11/26

Typing

Typing is the enforcement of the class of anobject, such that objects of different

types may not be interchanged, or at the

most, they may be interchanged only in

very restricted ways.

Function.prototype.StName = function () {

var st;st = this.toString();

return st;

}

String StName (){

String st;

st = this.toString()return st

}

String StName (){

Object st;

st = this.toString()

return (String) st

}

String StName (){

int st;

st = this.toString()

return st

}


12/26

Concurrency

Concurrency allows different objects to act at

the same time


13/26

Persistence

Persistence saves the state and class of an

object across time or space


14/26

Object ?

An object is an entity that has state, behavior, and identity. The

structure and behavior of similar objects are defined in their common

class. The terms instance and object are interchangeable.

The state of an object

encompasses all of the (usually

static) properties of the object

plus the current (usually dynamic)

values of each of these properties.

Behavior is how an object acts andreacts, in terms of its state changes

and message passing.

Identity is that property of an

object which distinguishes it from

all other objects


15/26

Relationships among Objects

Links, physical or conceptual connection between objects

Aggregation, denotes a whole/part hierarchy, with theability to navigate from the whole (also called theaggregate) to its parts

Aggregation is sometimes better because it encapsulates partsas secrets of the whole. Links are

sometimes better because they permit looser coupling amongobjects


16/26

Class

A class is a set of objects that share a common structure, common behavior, and

common semantics


17/26

Class: Interface vs Implementation

A Class may has Interface and Implementation

The interface of a class provides its outside view and therefore emphasizes the

abstraction while hiding its structure and the secrets of its behavior.

The implementation of a class primarily consists of the implementation of all

of the operations defined in the interface of the class.

// Student.cpp

// Implementation of the Class Student

#include "Student.h"

Student::Student(){

}

Student::~Student(){

}

boolean Student::cheating(char* bookTitle){

return NULL;

}

void Student::cheating(){

}

// Student.h

// Interface of the Class Student

class Student

{

public:

int age;

char* name;Student();

virtual ~Student();

boolean cheating(char* bookTitle);

private:

void cheating();

};


18/26

Class Relationships

Association

Inheritance (is a) Single Inheritance

Polymorphism

Multiple Inheritance

Aggregation (part of) containment by

value.

containment byreference.(composition)


19/26

Language Feature vs Concepts

C++class TempControl

{

public:

Heater m_Heater;

Termometer *m_Termometer;

};

Javapublic class TempControl {

public Heater m_Heater;

public Termometer m_Termometer;

}

No Differences in Java


20/26

Sample relationship in microsoft COM

Model Use for

Inheritance Exposing the managed object

as the outer object.

Aggregation Enabling the outer object to

expose another object's

implementation of an interface

without modification.

Containment Enabling the outer object tomodify the behavior of the

inner object.
http://msdn.microsoft.com/en-us/library/k3k086s0(VS.71).aspxhttp://msdn.microsoft.com/en-us/library/k3k086s0(VS.71).aspxhttp://msdn.microsoft.com/en-us/library/k3k086s0(VS.71).aspxhttp://msdn.microsoft.com/en-us/library/k3k086s0(VS.71).aspxhttp://msdn.microsoft.com/en-us/library/k3k086s0(VS.71).aspxhttp://msdn.microsoft.com/en-us/library/k3k086s0(VS.71).aspx


21/26

On Building Quality Classes and

Objects Coupling,

the measure of the strength of association established by a connection fromone module to another.

Strong coupling complicates a system since a module is harder to understand,change, or correct by itself if it is highly interrelated with other modules

Cohesion Cohesion measures the degree of connectivity among the elements of a single

module (and for object-oriented design, a single class or object)

Sufficiency the class or module captures enough characteristics of the abstraction to

permit meaningful and efficient interaction.

Completeness the interface of the class or module captures all of the meaningful

characteristics of the abstraction

Primitiveness Very Simple, basic


22/26

Classification

Classical categorization ( common property)

Conceptual clustering (meet concept)

Prototype theory


23/26

Candidates of class

Shlaer and Mellor

Tangible things: Cars, telemetry data, pressure

sensors

Roles: Mother, teacher, politician

Events: Landing, interrupt, request

Interactions: Loan, meeting, intersection


24/26

Candidates of class

Ross

People: Humans who carry out some function

Places : Areas set aside for people or things

Things : Physical objects, or groups of objects, that are Tangible

Organizations: Formally organized collections of people, resources,facilities, and capabilities having a defined mission, whose existenceis largely independent of individuals

Concepts: Principles or ideas not tangible per se; used to organizeor keep track of business activities and/or communications

Events: Things that happen, usually to something else at a

given date and time, or as steps in an ordered sequence


25/26

Coad Yourdon

StructureIs a and part of relationships

Other systems External systems with which the applicationinteracts

Devices Devices with which the application interacts Events remembered A historical event that must be

recorded

Roles played The different roles users play in interactingwith theapplication

Locations Physical locations, offices, and sites important tothe application

Organizational units Groups to which users belong


26/26

Bibliography

Booch, G., Maksimchuk, R. A., Engle, M. W.,

Young, B. J., Conallen, J., & Houston, K. A.

(2007). Object-Oriented Analysis and Design

with Applications (Third ed.). Massachusetts:Addison-Wesley.

002_a_pemrograman berorientasi object

Documents