A single system contains a large number of objects. A user can upload multiple attachments so the two classes are connected. This could further be defined using. ) Class diagrams are the main building blocks of every object-oriented method. In the previous modules you were introduced to object-oriented analysis and design, object-oriented modeling, and design principles. In this situation, using a sequence diagram, the polymorphic invocations are modeled by multiples scenarios controlled by the guard conditions. 2. In object-oriented programming, encapsulation is achieved through the use of objects. Mustang is an object of type Car. Berikut ini adalah komponen-komponennya: Komponen atas. View in full-text. organizational units. Abstraction. Abstract Operations. An aggregation describes a group of objects and how you interact with them. Create your first document, whether you import it, start from scratch, or use one of our templates. Study with Quizlet and memorize flashcards containing terms like Object modeling requires many types of diagrams, creating which by hand is very time consuming and tedious, so systems analysts rely on _____ to speed up the process. Object. In UML, multiplicity of aggregation and composition relationships can be specified, (similar to association relationship. The fields have not been added to the diagram yet. Sequence, Class and the Component Diagrams offered by UML and the Rational Rose Tool. A Brief Introduction to UMLAbstract. Engineering Practices for Building Quality Software: University of Minnesota. An animal as a single person as its owner. Class Diagrams and Encapsulation In a UML class diagram: public members can be preceded by + private members are preceded by - protected members are preceded by # 18 Die - numFaces: int - upValue : int + getUpValue() : int + getNumFaces() : int + roll() : void PairOfDice -die1: Die -die2: Die + getDie1() : Die + getDie2() : DieThe class diagram is the heart of UML. 4. Middle section – This section contains the attributes and supporting information about the. Edit this Template. Class. The UML Class diagram is a graphical notation that is used to construct and visualise object oriented systems. UML Diagram - Class. You can set properties and use keywords to create variations of these relationships. b. This project required Java codes and UML class diagram (including all the classes that are in the design) and it must be demonstrating Object Oriented Programming features: encapsulation, inheritance, polymorphism, abstract classes, interfaces. A picture is worth a thousand words, this idiom absolutely fits describing UML. A diagram is a partial representation of the model. Create professional UML diagrams to visualize complex systems. Le livre "UML 2 - de l'apprentissage à la pratique". It refers to the bundling of data with the methods that operate on that data. Essential elements of A UML class diagram 5. "In software engineering, a class diagram in the Unified Modeling Language (UML) is a type of static structure diagram that describes the structure of a system by showing the system's classes, their attributes, operations (or methods), and the relationships among objects. Therefore choice a is correct. Implement the given UML class diagrams using Java Console Application. Component diagrams are essentially class diagrams that focus on a. If we remove the book class, the whole Page class will be destroyed. A class diagram is a diagram used in designing and modeling software to describe classes and their relationships. Security Patterns Ronald Wassermann and Betty H. In UML,. Encapsulation is a fundamental concept in object-oriented programming (OOP) that refers to the bundling of data and the methods that operate on that data within a single unit. Konsep encapsulation menyebabkan sebuah konsep OOP yang bernama “Abstraction” atau “Data Hiding”. A Class in UML diagram is a blueprint used to create an object or set of objects. In summary, here are 10 of our most popular uml diagram courses. The four principles of object-oriented programming are encapsulation, abstraction, inheritance, and polymorphism. Class:. Now, in the final module of the course, given a description of new functionality. (Composition) 2. UML class is a classifier which describes a set of objects that share the same features, constraints, semantics (meaning). Encapsulation: The grouping of related concepts into one item, such as a class or component: Information hiding:. And notice, the class diagram is the only strict UML diagram, that can be converted to code and back. A UML relationship is a type of model element that adds semantics to a model by defining the structure and behavior between model elements. One of the more popular types in UML is the class diagram. We would like to show you a description here but the site won’t allow us. 1. Encapsulation: Encapsulation is hiding the details of an object from other objects. Le livre chez Amazon. So far we’ve been looking at what a class is and how it enables the key benefits of the object-oriented approach of system development: abstraction and encapsulation. Scanner; public class PersonnelDirectory { public static void main (String [] args) { Personnel per = new Personnel (); totalObjects total = new totalObjects (); Scanner scan. Study with Quizlet and memorize flashcards containing terms like 1. Class diagram adalah salah satu model dalam unified modelng language (UML) yang paling populer dan mudah dibuat. Directed Association. For example, a design class is a refinement of an analysis class. It is the technique of making the fields in a class private and providing access to the fields via public methods. It's time to get your hands dirty by drawing a Class Diagram of your own. The problem is that nothing is foreseen in UML to define such generic types. Encapsulation diagrams D. My question is about an "edge case" of the UML class diagram. The actor is a player. Abstraction has ______ types. b) False. Published on 2020-10-12. It also uses term completely encapsulated without appropriate explanation. So it might work fine on very simple diagrams but cause many issues on large ones. An aggregation is a special type of association in which objects are assembled or configured together to create a more complex object. Each method takes one additional parameter: an instance of the wrapper class. diagrams, and 720. For example, we treat duck as an animal and not just as a duck. a, information hiding) is closely related to abstraction. The class diagrams. AbstractFactory: Declares an interface for operations that create abstract product objects. Open the Model tab in the Element context tab group and check the Abstract checkbox in the Modifiers group. Namun, pada Class diagram desain modelnya dibagi menjadi 2 bagian. Custom methods are designed for a specific class. Class Diagram provides an overview of the target system by describing the objects and classes inside the system and the relationships between them. Example: class Car { - make: String - model: String - year: int + drive (): void + stop (): void } For this problem you are to join the following classes into a hierarchy (use the UML diagrams from Module 2 to get started): Player - Super Class Archer - Subclass Barbarian - Subclass Cleric - Subclass Rogue - Subclass Warlock - Subclass If the parent class has the same attributes as the sub class then you can remove those attributes from the subclass. Encapsulation adalah sebuah konsep Object Oriented Programming digunakan untuk membungkus data dan fungsi, untuk menjaga tetap terjaga agar tidak adanya penyalahgunaan. English: A class diagram is a type of static structure diagram in the Unified Modeling Language (UML), that describes the structure of a system by showing the system's classes, their attributes, and the relationships between the classes. Answer: a. a. - UML NOTATION OF LOCATION 2D - GIVEN GAMEDISPLAY CLASS JAVA CODE. Although many languages use terms such. Bizim bu yazımızda bahsedeceğimiz Class Diagram, Structure Diagram altında bulunmakta. Teachers give this quiz to your class. Aşağıda UML diyagramlarının kategorilerini görebiliyoruz. Aşağıda UML diyagramlarının kategorilerini görebiliyoruz. For our example, let's consider a basic e-commerce application with the following classes: Customer, Order, and Product. Phases. In class-based programming, the factory method pattern is a creational pattern that uses factory methods to deal with the problem of creating objects without having to specify the exact class of the object that will be created. In this situation, using a sequence diagram, the polymorphic invocations are modeled by multiples scenarios controlled by the guard conditions. UML Diagrams • UML stands for the Unified Modeling Language • UML diagrams show relationships among classes and objects • A UML class diagram consists of one or more classes, each with sections for the class name, attributes (data), and operations (methods) • Lines between classes represent associations Encapsulation is the separation of how a class is used from how its data is represented Abstraction is the related idea of hiding the details of how a class is implemented from its users Examples of these concepts will be given through an application that performs matrix algebra. 3 of 7. There are seven structure diagrams in UML 2. ISBN: 9781337569330. It is a standard which is mainly used for creating object-oriented, meaningful documentation models for any software system present in the real world. Renaming the list class would be a hint for the diagram reader. Follow the steps below: Open a blank document or a template. In this tutorial we use only a subset of UML; here, we introduce a UML class. whiteboard sketches, In a class diagram, each class. Trust me. The player rolls the dice. UML Component diagrams are used in modeling the physical aspects of object-oriented systems that are used for visualizing, specifying, and documenting component-based systems and also for constructing executable systems through forward and reverse engineering. Therefore, it is a fundamental component of UML. Inheritance is one of the key concepts of the OOP in which we can inherit the public properties and methods of the base class into the derived class. They can be split into two groups of similar classes. e. g. system is presented from a static structural point of view, i. The three major principles of OOP are; Encapsulation – this is concerned with hiding the implementation details and only exposing the methods. 2. Abstraction word is used for hiding data if our aim is to show our client a out side view. encapsulation. A class consists of its objects, and also it may inherit from other classes. The name is read in the same manner as for binary associations, described in the previous section. Data of an object is hidden from the rest of the system and available only through the services of the class. Goals of UML. 5. Pengertian Class Diagram ( Konsep) Class Diagram adalah salah satu jenis diagram yang paling berguna di UML, hal ini karena dapat dengan jelas memetakan struktur sistem tertentu dengan memodelkan kelas, atribut, operasi serta hubungan antar objek. Encapsulation adalah sebuah teknik untuk. Dynamic addressing b. In addition to the ability to perform the desired command, an Action may have an associated icon, keyboard shortcut, tooltip text, and so on. Website administration. It is a template to create various objects and implement their behavior in the system. e. Class diagram. The book represents an introduction to software modelling using UML as a modelling language. a. In diagram given below, we can see that aggregation is represented by an edge with a diamond end pointing towards superclass. The former is perfect at an early design stage. In particular, I have loads (about 30) classes that implement an interface. Generalization, Specialization, and Inheritance. Software engineering is a discipline utilizing Unified Modelling Language (UML) diagrams, which are accepted as a standard to depict object-oriented design models. FARID AZIS, M. Um dos tipos mais populares na UML é o diagrama de classes. An abstract class is intended to be used by other classifiers (e. Inheritance. Method: ReSECDI includes our customized design for extracting UML class diagram elements based on image processing technologies. Whiteboard Learn how to combine free-form brainstorming with diagram blueprints all while collaborating with your team. A class diagram is a UML diagram type that describes a system by visualizing the different types of objects within a system and the kinds of static relationships that exist among them. You can easily edit this template using Creately's class diagrams tool. 4. User input form b. In UML (Unified Modeling Language), “Class,” “Node,” and “Component” are three different elements used to represent various aspects of a system or software application. Association, aggregation, and inheritance relationships 3. 1. Class diagrams are most useful in illustrating relationships between classes and interfaces. UML diagrams of this category represent an entire system or a substructure. - Selection from Learning UML 2. Encapsulation - Hiding and/or restricting access to certain parts of a system, while exposing the necessary interfaces. In this section we introduce the UML class diagrams for modeling object-oriented software systems and various types of relations among the classes. Programming languages such as Java use encapsulation in the form of classes. Create a State base class that replicates the methods of the state machine interface. UML Class Diagrams: The Analysis Model A class diagram shows the existence of classes and their relationships in the logical view of a system UML modeling elements in class diagrams 1. Class Diagram is a UML diagram where you can visualize those classes, along with their attributes, operations and the inter-relationship. Class diagrams depict a static view of the model, or part of the model, describing what attributes and behavior it has rather than detailing the methods for achieving operations. Class diagrams, for example, consist of nodes that represent classes and interfaces and links that represent relationships among classes. You can add abstraction relationships to a model in several diagrams, including use-case, class, and component diagrams. A class diagram consists of a group of classes and interfaces reflecting important entities of the business domain of the system being modeled, and the relationships between these classes and interfaces. into four types of UML diagrams. I'm new to design patterns and UML class diagrams but from my understanding, the association relationship relates one object with another object; the aggregation relationship is a special kind of association that allows "a part" to belong to more than one "whole" (e. Factory Method lets a class defer instantiation to subclasses (Design Patterns: Elements of Reusable Object-Oriented Software). All these information can be output into HTML//PDF//MS Word formats. 2. Use Creately’s easy online diagram editor to edit this diagram, collaborate with others and export results to multiple. Encapsulation in OOPs is the concept of binding fields (object state) and methods (behavior) together as a single unit. Encapsulation: The attributes (instance variables) of the Bicycle class, such as gears, cost, weight, and color, are declared as private. > B C ---> B D. difference in both is just the View Point. The UML lollipop notation provides a compact description of an interface in a class diagram depicting a component type. Since a class consists of data. B) Use case diagram. Multiplicity and navigation indicators 4. Class diagrams, for example, consist of nodes that. Query Optimization | There is a fundamental. The improved hough transform (Duan et al. Address Date -number:int -day:int -month:int -city:string -year:int -country:String +convert Month ():String Book Publisher -author:String -title:String -pubDate:Date. The first represents the name of the class as defined in Java. In an abstraction relationship, one model element, the client, is more refined or detailed than the other, the supplier. Building class diagrams is not a quick and easy thing for people (especially non-programmers) to get started doing. UML serves a great way of. Network+ Guide to Networks (MindTap Course List) Computer Engineering. Think about encapsulation, side effects, the Law of Demeter. Classes are at the heart of any object-oriented system; therefore, it follows that the most popular UML diagram is the class diagram. For example, a Car class can extend (inherit from) a Vehicle class; a Cat class can extend an Animal class, etc. This way, you could mix qualifier and quantifier: @startuml class class1 class class2 class1 [Qualifier] "1" -- class2 @enduml. Class diagram yang pertama merupakan. •UML is a diagramming tool for describing and documenting object oriented applications •Programming language independent •Used for modelling an application before its engineered •Twelve different diagrams in all, with many complex details •Generally though only two of these are used regularly •Class diagrams •Sequence diagrams 16 Structural UML Diagrams – Class Diagram – The most widely use UML diagram is the class diagram. Class Diagram Example. They are usually used to explore domain concepts, understand software requirements and describe. UML class diagrams • UML class diagram: a picture of –the classes in an OO system –their fields and methods –connections between the classes • that interact or inherit from each other • Notrepresented in a UML class diagram: –details of how the classes interact with each other –algorithmic details; how a particular behavior is. * The Free edition supports free usage of Visual Paradigm Online for non-commercial use only. It is quite simple to create a class diagram from scratch. Use class abstraction and encapsulation concepts to modify the implementation of Square class, so the new class implementation would. i want to model this scenario in class diagram and then implement it in code. A class is a key construct in many object-oriented languages. 0 pada bulan Januari 1997. Encapsulation (a. Implementation defines the components assembled together to make a complete physical system. this is a scenario in book store. Encapsulation [classic] Use Creately’s easy online diagram editor to edit this diagram, collaborate with others and export results to multiple image formats. An object is a real-world entity. Encapsulation is one of the fundamentals of OOP (object-oriented programming). A. convertMonth() – converts the numeric input. Encapsulation Inheritance Polymorphism Abstraction ; 3. Implement the given UML class diagrams using Java Console Application. The class diagram is. The Main class uses FileIO, Login, Shop, and Pikachu. Encapsulation – Data in objects is private. ABCMeta and implements the abstract method write(). UML Association; Naming Relationships; Naming Roles; Relationships and Encapsulation; Relationships and Multiplicity; Association in Java and C++ compared; Aggregation vs. Composition. Class Diagrams and Encapsulation In a UML class diagram: public members can be preceded by + private members are preceded by - protected members are preceded by. The message parameters, as well as the type of data, may be included on the class diagram. 4. In this. Upload media. Now. The UML diagrams are made for business users, developers, ordinary people, or anyone who is looking forward to understand the system, such that the system can be software or non-software. A model should. A UML _____ is a structural diagram that can be used to visually model the classes of a computer program, including data members and functions. Use case diagram c. On the next slide, note the three computers on a conveyer belt in a manufacturing plant: The three computers represent objects, and the specifications document represents a class. UML diagrams are closely associated with object-oriented analysis and. Popular among software engineers to document software architecture, class diagrams are a type of structure diagram because they describe what must be present in the system being modeled. There are two types of methods: standard and custom. La version éditée est pratiquement deux fois plus volumineuse que la version en ligne ; des séances de travaux dirigés et de travaux pratiques accompagnées de corrigés complets et détaillés ; une présentation bien plus agréable sous la forme d'un vrai livre. The class diagram depicts a static view of an application. Support code generation. The UML diagram is the superclass of the ER diagram. UML is used in modeling complex object oriented software systems and thus the language is thorough. The C++ concepts defines constraints on the types associated with a template class:. The simple idea is that any class has public and private elements. Class A/an __________ is a code blueprint for creating an object that is composed of data members and functions that operate on those data members. Class diagrams depict a static view of the model, or part of the model, describing what attributes and behavior it has rather than detailing the methods for achieving operations. Practice. These. Class diagrams are most useful in illustrating relationships between classes and interfaces. Abstraction. com With encapsulation, the fields in a class can be hidden from other classes, and the methods in a class can be modified or improved without changing the way that other classes use them. It. This is the UML Class diagram. The Unified Modeling Language (UML) can help you model systems in various ways. UML Class Diagrams Weeks 8-9, UML Class and Encapsulation; Java Class and Encapsulation; UML Utility Class; Java Utility Class; Parameterized Class in UML;. Follow the steps below: Open a blank document or a template. You don’t need an expensive tool for this. In UML (Unified Modeling Language), “Class,” “Node,” and “Component” are three different elements used to represent various aspects of a system or software application. Implicitly, an instantiated object of the Circle class will have attributes x_position, y_position and radius and a method display(). So it might work fine on very simple diagrams but cause many issues on large ones. Java Encapsulation is a way of hiding the implementation details of a class from outside access and only exposing a. Encapsulation - Data in objects is private. Nice example. Encapsulation word is used for hiding data if our aim is to prevent client seeing inside view of our logic. 2. Person class has attributes name, birthDate, gender and homeAddress. Figure 3 is the Use Case Diagram for the actions that the Users (Seller, Purchaser) can perform in an auction. (1) Select the Fortran source code (2) Select the location to save the output. In OOP programming, a class is a blueprint for creating objects. " -Wikipedia. The main purpose of encapsulation is to; Reduce software development complexity – by hiding the implementation details and only exposing the. Explanation: Encapsulation is the object-oriented principle that specifies that an objects data should be guarded from inappropriate access. Classes and interfaces in UML show architecture and features of the designed system. Sequence diagrams E. 1 Basic UML class diagram symbols and notations. The dice game described by Craig Larman in Applying UML and Patterns begins with a use case: Play a Game. Cheng⁄ Software Engineering and Network Systems Laboratory Department of Computer Science and EngineeringUML component diagrams show the relationships between individual system components through a static conceptual visualization. Role of Data Analysis in Orgs (DAT-205) 86 Documents. You would then define concepts exactly like classes, define the constraints using the UML constraints, and use the concepts in UML class templates. The following diagram shows a parent class generalizing a child class. Each class represents a distinct entity or concept in your software system. Similarly we treat dog and cat also as animals. We may assume that in UML 2. First, about the syntax we propose to have: @startuml class class1 class class2 class1 [Qualifier] -- class2 @enduml. This model is NOT a UML diagram however. Class diagram atau diagram kelas merupakan suatu diagram yang digunakan untuk menampilkan kelas-kelas berupa pake-paket untuk memenuhi salah satu kebutuhan paket yang akan digunakan nantinya. This interface is implemented in two classes. Name represents full name and could be combined from title, first. Encapsulation is used to hide the values or state of a structured data object inside a class, preventing unauthorized parties’ direct access to them. Mekanisme ini membungkus seluruh. polymorphism. It helps to understand the entities in the real world and how they interact with each other. It is used with classes, packages, generalizations, element import, package import. The. 2 a declaring class and a class in its namespace may be shown connected by a line, with an "anchor" icon on the end connected to a declaring class (namespace). ISBN: 9781337569330. Shop has Items and Food, and Pikachu has Pictures and Money. But you could as well consider to. Encapsulation, in object oriented programming methodology, prevents access to implementation details. The function call is resolved at runtime, depending on the actual type of the object. Object Diagram. Right-click on the class and choose Modifiers/Abstract from the context menu. 2. Diagram UML . Even if we remove the Classroom class, the Students class does not need to destroy, which means we can use Student class independently. UML is used in modeling complex object oriented software systems and thus the language is thorough. UML, viết tắt của Unified Modeling Language, là ngôn ngữ mô hình hóa thống nhất gồm các ký hiệu đồ họa được sử dụng để xây dựng và trực quan hóa các hệ thống hướng. This week’s class about object oriented programming is very useful for our IA development. For each member (an attribute or a method), there is an access modifier, such as public or private, to control which classes have access to it. Generalization - Indicates that one class is a. The composition relationship is represented by a straight line with a black diamond at one end. Software protection and licensing UML use. Start a UML diagram in Lucidchart in minutes. Select Model | Add | Use Case in Menu Bar or Add |. In Assignment Part 2 OO Programming, you will work individually to implement the design in code, which you will. I want to install/enable the NetBeans plugin for creating and viewing UML diagrams, as seen here. and it shows how inheritance forms a hierarchy of related classes. Discuss: Do you think the data field (side) should. Solution for Question2: Create the class encapsulation of student course of given UML diagram: Course - courseName : String -instructor : Instructor -textBook :…UML diagrams can show the structure of a system and its components like classes, packages, and objects. UML 2. Select Use Case in Toolbox. Address Date -number:int -day:int -month:int -year:int -city:string -country:string +convertMonth ():String. Draw Now. 1. The Class Model in the UML is the main artifact produced to represent the logical structure of a software system. (Composition) 2. Bank ATM UML use case diagrams examples. In software engineering, a class diagram in the Unified Modeling Language (UML) is a type of static structure diagram that describes the structure of a system by showing the system's classes, their attributes, operations (or methods), and the relationships among objects. In this case, he pushes encapsulation to the excess but the idea is right. encapsulation: In general, encapsulation is the inclusion of one thing within another thing so that the included thing is not apparent. UML class diagrams show the classes of the system, their inter-relationships, and the operations and attributes of the classes. A single class diagram describes a specific aspect of the system and the collection of class diagrams represents the whole system. Use Lucidchart’s UML shape library to access industry-standard UML shapes. Encapsulation is a key concept in object-oriented programming (OOP), where everything revolves around objects. We would like to show you a description here but the site won’t allow us. utilizing the standardized UML diagram format. Linear addressing, _____ describes how instances of one class relate to instances of another class. This set of Software Engineering Multiple Choice Questions & Answers (MCQs) focuses on “Unified Modelling Language”. Classes are shown as boxes with three sections – the top for the name of the class, the middle for the attributes, and the bottom for the operations. 456). Aggregation relationship is represented by a straight line with an empty diamond at one end. UML Class Diagrams Weeks 8-9, UML Class and Encapsulation Java Class and Encapsulation UML Utility Class Java Utility Class Parameterized Class in UML. Active class is used in a class diagram to represent the concurrency of the system. Each of these elements has a specific purpose and is used in different contexts within a UML diagram. Stated simply, the top class in an inheritance hierarchy represents a general "thing," and lower classes are more specific. Abstract and Figures. The first part is a functional model, which. Now, age cannot be negative. Collaborate in real-time by sharing a link to your design. whiteboard sketches, In a class diagram, each class appears as a(n) _____, with the class name at the. a. To create an Use Case (model element only) by Menu: 1. Encapsulation Object Diagrams Advanced Class Diagram Concepts De nitions Kinds of Encapsulation There are two kinds of encapsulation: aggregation and composition. It is a fundamental building block of UML. Which statement invokes drive ()? mustang. In UML, it can exist between two or more classes. How do I represent or show encapsulation when modelling a UML class diagram? Inheritance is modelled using the arrows and an abstract class is shown by having the class name in italics or between the following arrows as shown, << Animals >> but what do you do for encapsulation? See full list on stackify. Inheritance. Class Diagram adalah diagram yang menunjukan class-class yang ada dari sebuah sistem dan hubungannya secara logika. kinds of static relationships that exist among them. UML provides class diagram, object diagram to support this. The ER diagram is the pictorial representation of the objects and their relationships. Figure 1 presents a class diagram that models a banking system. The “Library Management System” is superclass that consists of various. A Social Media Class Diagram is a UML (Unified Modeling Language) entity-relationship model, that visualizes the thought process of building a application or system. The internal structure of a collaboration as comprised by roles and. Class diagrams. A class is a template or blueprint that defines the properties and behaviors of a set of objects. This can be achieved with the use of access modifiers, Getters,. Both logical and physical modelling aspects can be included. UML diagramming notes. And the complex, excessively long explanations in Wikipedia sometimes double the confusion. Machine Problem/Problem Exercise 1. Encapsulation in Java is a fundamental concept in object-oriented programming (OOP) that refers to the bundling of data and methods that operate on that data within a single unit, which is called a class in Java. La version éditée est pratiquement deux fois plus volumineuse que la version en ligne ; des séances de travaux dirigés et de travaux pratiques accompagnées de corrigés complets et détaillés ; une présentation bien plus agréable sous la forme d'un vrai livre. Chapter 4. 2. , 2010) can detect lines with the polar coordinate function, which might be useful for UML relationship detection. ', and so on. 4 specification provides no definition of encapsulation. Class diagrams are most often used in the elaboration and construction phase of software projects. Expert Answer. Hence, the same elements as used in Design are also used to support this. Atribut, yaitu variabel-variabel yang dimiliki suatu kelas. Discuss: Do you think the data field (side) should be declared private (hidden)?.