Object modeling involves identifying important objects (classes) within a system and defining their attributes, operations, and relationships. During object modeling, classes are identified based on system requirements and domain concepts. Key activities include class identification, defining class attributes and methods, and determining associations between classes. Object modeling results in a visual representation of classes and their relationships in class and other diagrams.
The document discusses advanced structural modeling concepts in object-oriented software engineering, including advanced classes, relationships, interfaces, types and roles, packages, and object diagrams. It defines these concepts and provides examples to illustrate their usage and relationships.
This document discusses classes and objects in object-oriented analysis and design. It defines objects as having state, behavior, and identity, with similar objects defined by common classes. Classes represent groups of objects with similar behavior and structures. The relationships between classes and objects are explored, including generalization, aggregation, and association. Identification of classes and objects in analysis is discussed through various approaches like use case analysis and CRC cards. The importance of proper classification and key abstractions and mechanisms are also covered.
The document discusses the key elements of the object model, including abstraction, encapsulation, modularity, and hierarchy. It explains that abstraction is one of the fundamental ways to cope with complexity in software design. Abstraction focuses on the essential characteristics of an object that distinguish it from other objects, from the perspective of the viewer. The object model provides a conceptual framework for object-oriented programming that is based on these elements.
Object modeling represents the static structure of objects and their relationships using object diagrams. An object diagram shows instances of classes, their attributes and values, and relationships between objects through links representing associations, generalizations, or aggregations. Object diagrams are useful for understanding object behavior and relationships in a system, as well as its static view and for forward and reverse engineering.
This slide give the basic introduction about UML diagram and it's types, and brief intro about Activity Diagram, use of activity diagram in object oriented programming language..
This document discusses design patterns, beginning with how they were introduced in architecture in the 1950s and became popularized by the "Gang of Four" researchers. It defines what patterns are and provides examples of different types of patterns (creational, structural, behavioral) along with common patterns in each category. The benefits of patterns are that they enable reuse, improve communication, and ease the transition to object-oriented development. Potential drawbacks are that patterns do not directly lead to code reuse and can be overused. Effective use requires applying patterns strategically rather than recasting all code as patterns.
This document provides an overview of object-oriented databases. It introduces object-oriented programming concepts like encapsulation, polymorphism and inheritance. It then discusses how object-oriented databases combine these concepts with database principles like ACID properties. Advantages include being integrated with programming languages and automatic method storage. Disadvantages include requiring object-oriented programming and high costs to convert data. The document also discusses the Object Query Language and provides an example query in OQL.
This document discusses class diagrams and object diagrams. Class diagrams model the static design of a system by describing classes and their attributes/methods. Object diagrams show instances of classes at a specific time by depicting objects and their relationships. Key differences are that class diagrams define types while object diagrams show state, and class diagrams are blueprints while object diagrams capture snapshots.
The document discusses advanced structural modeling concepts in object-oriented software engineering, including advanced classes, relationships, interfaces, types and roles, packages, and object diagrams. It defines these concepts and provides examples to illustrate their usage and relationships.
This document discusses classes and objects in object-oriented analysis and design. It defines objects as having state, behavior, and identity, with similar objects defined by common classes. Classes represent groups of objects with similar behavior and structures. The relationships between classes and objects are explored, including generalization, aggregation, and association. Identification of classes and objects in analysis is discussed through various approaches like use case analysis and CRC cards. The importance of proper classification and key abstractions and mechanisms are also covered.
The document discusses the key elements of the object model, including abstraction, encapsulation, modularity, and hierarchy. It explains that abstraction is one of the fundamental ways to cope with complexity in software design. Abstraction focuses on the essential characteristics of an object that distinguish it from other objects, from the perspective of the viewer. The object model provides a conceptual framework for object-oriented programming that is based on these elements.
Object modeling represents the static structure of objects and their relationships using object diagrams. An object diagram shows instances of classes, their attributes and values, and relationships between objects through links representing associations, generalizations, or aggregations. Object diagrams are useful for understanding object behavior and relationships in a system, as well as its static view and for forward and reverse engineering.
This slide give the basic introduction about UML diagram and it's types, and brief intro about Activity Diagram, use of activity diagram in object oriented programming language..
This document discusses design patterns, beginning with how they were introduced in architecture in the 1950s and became popularized by the "Gang of Four" researchers. It defines what patterns are and provides examples of different types of patterns (creational, structural, behavioral) along with common patterns in each category. The benefits of patterns are that they enable reuse, improve communication, and ease the transition to object-oriented development. Potential drawbacks are that patterns do not directly lead to code reuse and can be overused. Effective use requires applying patterns strategically rather than recasting all code as patterns.
This document provides an overview of object-oriented databases. It introduces object-oriented programming concepts like encapsulation, polymorphism and inheritance. It then discusses how object-oriented databases combine these concepts with database principles like ACID properties. Advantages include being integrated with programming languages and automatic method storage. Disadvantages include requiring object-oriented programming and high costs to convert data. The document also discusses the Object Query Language and provides an example query in OQL.
This document discusses class diagrams and object diagrams. Class diagrams model the static design of a system by describing classes and their attributes/methods. Object diagrams show instances of classes at a specific time by depicting objects and their relationships. Key differences are that class diagrams define types while object diagrams show state, and class diagrams are blueprints while object diagrams capture snapshots.
This document discusses ADO.NET, which is a data access technology that allows applications to connect to and manipulate data from various sources. It describes the core ADO.NET objects like Connection, Command, DataReader, DataAdapter, DataSet and DataTable. It also explains the differences between connected and disconnected data access models in ADO.NET, detailing the objects used in each approach and their advantages. Finally, it provides an overview of commonly used .NET data providers like SqlClient, OleDb and Odbc.
This document discusses several key concepts in object-oriented analysis and design (OOAD):
1. Traditional development methodologies are either algorithm-centric or data-centric, focusing on algorithms or data structure first.
2. Objects have attributes that describe their state and methods that define their behavior. An object represents a real-world entity like a car with attributes like color and methods like drive.
3. Object behavior is described through methods, which encapsulate what an object can do. Objects take responsibility for their own behavior.
The document discusses use case diagrams in UML modeling. It defines key components of use case diagrams including use cases, actors, the system boundary, and relationships like include, extend, and generalization. It provides examples of how to construct a use case diagram based on system functions and user goals. Specific use case diagram examples shown include an online ordering system and a vending machine.
This document discusses the object oriented data model (OODM). It defines the OODM and describes how it accommodates relationships like aggregation, generalization, and particularization. The OODM provides four types of data operations: defining schemas, creating databases, retrieving objects, and expanding objects. Key features of the OODM include object identity, abstraction, encapsulation, data hiding, inheritance, and classes. The document concludes that a prototype of the OODM has been implemented to model application domains and that menus can be created, accessed, and updated like data from the database schema in the OODM.
The objective is to explain how a software design may be represented as a set of interacting objects that manage their own state and operations and to introduce various models that describe an object-oriented design.
This document provides an overview of class diagrams in UML. It describes the key components of a class diagram including classes, attributes, operations, and relationships. A class represents a set of objects with common properties and behavior. It includes a name, attributes, and operations. Relationships between classes such as dependencies, generalizations, and associations are also depicted. The document provides examples of how to represent these components and relationships in a UML class diagram.
UML (Unified Modeling Language) is a diagramming language used for object-oriented programming. It can be used to describe the organization, execution, use, and deployment of a program. Design patterns describe common solutions to programming problems and always use UML diagrams. This document focuses on class diagrams, which show classes, interfaces, and their relationships. It provides examples of how to depict classes with variables and methods, and relationships between classes like inheritance.
UML component diagrams describe the structure of software systems by showing components, their interfaces, and dependencies between components. A component represents a modular part of a system that encapsulates its contents and exposes its functionality through interfaces. Component diagrams show the organization and dependencies of components through their interfaces and ports using elements like components, interfaces, ports, and connectors. They allow modeling large and complex software systems in a modular way.
CORBA and DCOM are specifications for distributed computing that allow objects to communicate across a network. CORBA uses an Object Request Broker (ORB) as middleware to locate and invoke remote objects transparently. It defines an Interface Definition Language (IDL) and supports location transparency. DCOM is Microsoft's version that extends COM to allow components to interact remotely. It uses proxies on the client side and stubs on the server side to marshal requests and responses.
This document provides an overview of object-oriented analysis and design. It defines key terms and concepts in object-oriented modeling like use cases, class diagrams, states, sequences. It describes developing requirements models using use cases and class diagrams. It also explains modeling object behavior through state and sequence diagrams and transitioning analysis models to design.
This document provides an overview of UML class diagrams, including their purpose and essential elements. A UML class diagram visually describes the structure of a system by showing classes, attributes, operations, and relationships. Key elements include classes, associations, generalization, dependencies, and notes. The document also provides examples and tips for creating UML class diagrams.
Type constructor concepts where the examples are clearly described and points are easy to understand. Every point is clearly connected once we go through ppts.
A class diagram shows the structure of a system through classes, attributes, operations, and relationships between classes. It includes classes and their properties like attributes and methods. It also shows relationships between classes like associations, aggregations, generalizations, and dependencies. The class diagram is a key tool in object-oriented analysis and design.
Structured Vs, Object Oriented Analysis and DesignMotaz Saad
This document discusses structured vs object-oriented analysis and design (SAD vs OOAD) for software development. It outlines the phases and modeling techniques used in SAD like data flow diagrams, decision tables, and entity relationship diagrams. It also outlines the phases and modeling techniques used in OOAD like use cases, class diagrams, sequence diagrams, and state machine diagrams. The document compares key differences between SAD and OOAD, discusses textbooks on software engineering and UML, and references papers on using UML in practice and evaluating the impact and costs/benefits of UML in software maintenance.
The document provides an overview of object-oriented concepts. It discusses that software development is increasingly relying on object-oriented paradigms due to benefits like improved modeling of real-world problems and reusability. Key concepts discussed include classes and objects, encapsulation, inheritance, polymorphism, and object composition. Various object-oriented methodologies like those proposed by Coad/Yourdon, Booch, Rumbaugh, and Jacobson are also summarized.
UML (Unified Modeling Language) is a standard modeling language used to specify, visualize, and document software systems. It uses graphical notations to model structural and behavioral aspects of a system. Common UML diagram types include use case diagrams, class diagrams, sequence diagrams, and state diagrams. Use case diagrams model user interactions, class diagrams show system entities and relationships, sequence diagrams visualize object interactions over time, and state diagrams depict object states and transitions. UML aims to simplify the complex process of software design through standardized modeling.
This document defines and explains the key elements of a sequence diagram:
- Sequence diagrams show the interactions between objects through messages over time.
- Objects are represented by vertical lifelines and may send/receive synchronous, asynchronous, reflexive, return, create, and destroy messages.
- Activation bars on lifelines indicate when an object is active.
- Time progresses downward on the diagram, showing the order of messages.
- Events mark specific points of interaction like sending and receiving messages.
This chapter discusses basic structural modeling in object oriented software engineering. It covers classes and relationships, common mechanisms, diagrams, and class diagrams, which are used to model the basic structure of a software system using objects and their interactions.
This document discusses key concepts in software design engineering including analysis models, design models, the programmer's approach versus best practices, purposes of design, quality guidelines, design principles, fundamental concepts like abstraction and architecture, and specific design concepts like patterns, modularity, and information hiding. It emphasizes that design is important for translating requirements into a quality software solution before implementation begins.
Object oriented concepts can be summarized in 3 sentences:
Objects have state, behavior, and identity. State represents the properties and values of an object, behavior is defined by the operations or methods that can be performed on an object, and identity uniquely distinguishes one object from all others. Key concepts in object orientation include abstraction, encapsulation, modularity, hierarchy, polymorphism, and life span of objects. These concepts help organize programs through the definition and use of classes and objects.
This document discusses ADO.NET, which is a data access technology that allows applications to connect to and manipulate data from various sources. It describes the core ADO.NET objects like Connection, Command, DataReader, DataAdapter, DataSet and DataTable. It also explains the differences between connected and disconnected data access models in ADO.NET, detailing the objects used in each approach and their advantages. Finally, it provides an overview of commonly used .NET data providers like SqlClient, OleDb and Odbc.
This document discusses several key concepts in object-oriented analysis and design (OOAD):
1. Traditional development methodologies are either algorithm-centric or data-centric, focusing on algorithms or data structure first.
2. Objects have attributes that describe their state and methods that define their behavior. An object represents a real-world entity like a car with attributes like color and methods like drive.
3. Object behavior is described through methods, which encapsulate what an object can do. Objects take responsibility for their own behavior.
The document discusses use case diagrams in UML modeling. It defines key components of use case diagrams including use cases, actors, the system boundary, and relationships like include, extend, and generalization. It provides examples of how to construct a use case diagram based on system functions and user goals. Specific use case diagram examples shown include an online ordering system and a vending machine.
This document discusses the object oriented data model (OODM). It defines the OODM and describes how it accommodates relationships like aggregation, generalization, and particularization. The OODM provides four types of data operations: defining schemas, creating databases, retrieving objects, and expanding objects. Key features of the OODM include object identity, abstraction, encapsulation, data hiding, inheritance, and classes. The document concludes that a prototype of the OODM has been implemented to model application domains and that menus can be created, accessed, and updated like data from the database schema in the OODM.
The objective is to explain how a software design may be represented as a set of interacting objects that manage their own state and operations and to introduce various models that describe an object-oriented design.
This document provides an overview of class diagrams in UML. It describes the key components of a class diagram including classes, attributes, operations, and relationships. A class represents a set of objects with common properties and behavior. It includes a name, attributes, and operations. Relationships between classes such as dependencies, generalizations, and associations are also depicted. The document provides examples of how to represent these components and relationships in a UML class diagram.
UML (Unified Modeling Language) is a diagramming language used for object-oriented programming. It can be used to describe the organization, execution, use, and deployment of a program. Design patterns describe common solutions to programming problems and always use UML diagrams. This document focuses on class diagrams, which show classes, interfaces, and their relationships. It provides examples of how to depict classes with variables and methods, and relationships between classes like inheritance.
UML component diagrams describe the structure of software systems by showing components, their interfaces, and dependencies between components. A component represents a modular part of a system that encapsulates its contents and exposes its functionality through interfaces. Component diagrams show the organization and dependencies of components through their interfaces and ports using elements like components, interfaces, ports, and connectors. They allow modeling large and complex software systems in a modular way.
CORBA and DCOM are specifications for distributed computing that allow objects to communicate across a network. CORBA uses an Object Request Broker (ORB) as middleware to locate and invoke remote objects transparently. It defines an Interface Definition Language (IDL) and supports location transparency. DCOM is Microsoft's version that extends COM to allow components to interact remotely. It uses proxies on the client side and stubs on the server side to marshal requests and responses.
This document provides an overview of object-oriented analysis and design. It defines key terms and concepts in object-oriented modeling like use cases, class diagrams, states, sequences. It describes developing requirements models using use cases and class diagrams. It also explains modeling object behavior through state and sequence diagrams and transitioning analysis models to design.
This document provides an overview of UML class diagrams, including their purpose and essential elements. A UML class diagram visually describes the structure of a system by showing classes, attributes, operations, and relationships. Key elements include classes, associations, generalization, dependencies, and notes. The document also provides examples and tips for creating UML class diagrams.
Type constructor concepts where the examples are clearly described and points are easy to understand. Every point is clearly connected once we go through ppts.
A class diagram shows the structure of a system through classes, attributes, operations, and relationships between classes. It includes classes and their properties like attributes and methods. It also shows relationships between classes like associations, aggregations, generalizations, and dependencies. The class diagram is a key tool in object-oriented analysis and design.
Structured Vs, Object Oriented Analysis and DesignMotaz Saad
This document discusses structured vs object-oriented analysis and design (SAD vs OOAD) for software development. It outlines the phases and modeling techniques used in SAD like data flow diagrams, decision tables, and entity relationship diagrams. It also outlines the phases and modeling techniques used in OOAD like use cases, class diagrams, sequence diagrams, and state machine diagrams. The document compares key differences between SAD and OOAD, discusses textbooks on software engineering and UML, and references papers on using UML in practice and evaluating the impact and costs/benefits of UML in software maintenance.
The document provides an overview of object-oriented concepts. It discusses that software development is increasingly relying on object-oriented paradigms due to benefits like improved modeling of real-world problems and reusability. Key concepts discussed include classes and objects, encapsulation, inheritance, polymorphism, and object composition. Various object-oriented methodologies like those proposed by Coad/Yourdon, Booch, Rumbaugh, and Jacobson are also summarized.
UML (Unified Modeling Language) is a standard modeling language used to specify, visualize, and document software systems. It uses graphical notations to model structural and behavioral aspects of a system. Common UML diagram types include use case diagrams, class diagrams, sequence diagrams, and state diagrams. Use case diagrams model user interactions, class diagrams show system entities and relationships, sequence diagrams visualize object interactions over time, and state diagrams depict object states and transitions. UML aims to simplify the complex process of software design through standardized modeling.
This document defines and explains the key elements of a sequence diagram:
- Sequence diagrams show the interactions between objects through messages over time.
- Objects are represented by vertical lifelines and may send/receive synchronous, asynchronous, reflexive, return, create, and destroy messages.
- Activation bars on lifelines indicate when an object is active.
- Time progresses downward on the diagram, showing the order of messages.
- Events mark specific points of interaction like sending and receiving messages.
This chapter discusses basic structural modeling in object oriented software engineering. It covers classes and relationships, common mechanisms, diagrams, and class diagrams, which are used to model the basic structure of a software system using objects and their interactions.
This document discusses key concepts in software design engineering including analysis models, design models, the programmer's approach versus best practices, purposes of design, quality guidelines, design principles, fundamental concepts like abstraction and architecture, and specific design concepts like patterns, modularity, and information hiding. It emphasizes that design is important for translating requirements into a quality software solution before implementation begins.
Object oriented concepts can be summarized in 3 sentences:
Objects have state, behavior, and identity. State represents the properties and values of an object, behavior is defined by the operations or methods that can be performed on an object, and identity uniquely distinguishes one object from all others. Key concepts in object orientation include abstraction, encapsulation, modularity, hierarchy, polymorphism, and life span of objects. These concepts help organize programs through the definition and use of classes and objects.
This document discusses software quality and metrics. It defines software quality as conformance to requirements, standards, and implicit expectations. It outlines ISO 9126 quality factors like functionality, reliability, usability, and maintainability. It describes five views of quality: transcendental, user, manufacturing, product, and value-based. It also discusses types of metrics like product, process, and project metrics. Product metrics measure characteristics like size, complexity, and quality level. The document provides guidelines for developing, collecting, analyzing, and interpreting software metrics.
The document provides an overview of architectural design in software engineering. It defines software architecture as the structure of components, relationships between them, and properties. The key steps in architectural design are creating data design, representing structure, analyzing styles, and elaborating chosen style. It emphasizes software components and their focus. Examples of architectural styles discussed include data flow, call-and-return, data-centered, and virtual machine.
Unit 7 performing user interface designPreeti Mishra
The document discusses user interface design principles and models. It provides three key principles for user interface design:
1. Place users in control of the interface and allow for flexible, interruptible, and customizable interaction.
2. Reduce users' memory load by minimizing what they need to remember, establishing defaults, and progressively disclosing information.
3. Make the interface consistent across screens, applications, and interaction models to maintain user expectations.
It also describes four models involved in interface design: the user profile model, design model, implementation model, and user's mental model. The role of designers is to reconcile differences across these models.
The document discusses component-based software engineering and defines a software component. A component is a modular building block defined by interfaces that can be independently deployed. Components are standardized, independent, composable, deployable, and documented. They communicate through interfaces and are designed to achieve reusability. The document outlines characteristics of components and discusses different views of components, including object-oriented, conventional, and process-related views. It also covers topics like component-level design principles, packaging, cohesion, and coupling.
software development, process model, requirement engineering, srs, structured...Ashok Mohanty
This document provides an overview of software engineering. It begins by discussing the emergence of software engineering as a discipline due to the "software crisis" of the 1970s. It then covers various software engineering processes and lifecycle models, including sequential models like waterfall and iterative models like prototyping and spiral. Requirements engineering methods like elicitation, analysis and specification are also summarized. Finally, it discusses the function-oriented and object-oriented approaches to software development.
Rumbaugh's Object Modeling Technique (OMT) is an object-oriented analysis and design methodology. It uses three main modeling approaches: object models, dynamic models, and functional models. The object model defines the structure of objects in the system through class diagrams. The dynamic model describes object behavior over time using state diagrams and event flow diagrams. The functional model represents system processes and data flow using data flow diagrams.
Architecture design in software engineeringPreeti Mishra
The document discusses software architectural design. It defines architecture as the structure of a system's components, their relationships, and properties. An architectural design model is transferable across different systems. The architecture enables analysis of design requirements and consideration of alternatives early in development. It represents the system in an intellectually graspable way. Common architectural styles structure systems and their components in different ways, such as data-centered, data flow, and call-and-return styles.
The document provides an overview of design patterns, including what they are, why they are used, how to apply them, examples of common patterns, and an example application to expense reporting. Design patterns solve common programming problems by describing core solutions that can be reused in different situations, with the intent of increasing code reuse and flexibility. The document discusses several fundamental design patterns including creational, structural, and behavioral patterns, provides UML diagrams to illustrate the relationships between pattern participants, and gives a detailed example of how patterns could be applied to validate expense reports against business policies.
This document discusses object-oriented modeling and design. It provides an overview of key concepts in object-oriented thinking like objects, classes, polymorphism, and inheritance. It also describes object-oriented methodology, including analysis, system design, object design, and implementation. Additionally, it discusses object modeling technique (OMT) and the unified modeling language (UML), including the four main views (use case view, design view, process view, and implementation view) used in UML architecture.
The document summarizes several common design patterns organized into categories - creational, structural, behavioral, architectural, concurrency, and cloud patterns. Each pattern includes an intent describing the problem it addresses and a use case example. The document provides an overview of key design patterns and their purposes without delving into detailed explanations of each pattern.
The document provides an overview of object-oriented analysis and design. It discusses key concepts in object-oriented modeling including objects, classes, inheritance, polymorphism, associations, aggregation, generalization, and state diagrams. It also describes object-oriented development processes involving modeling concepts, methodology, and three main models - object/class models, dynamic/state models, and functional/interaction models. The document is intended as an introduction to object-oriented analysis and design principles and techniques.
Object oriented analysis_and_design_v2.0Ganapathi M
This is the presentation I have been using to discuss OOAD concepts with the new joiners of the my company. Quick refresher, but will give the paradigm shift for the participants on how OOAD is different in theory & practice.
The document discusses key concepts in object-oriented analysis and design including objects, classes, attributes, operations, relationships, inheritance, and polymorphism. It also provides an overview of the software development life cycle (SDLC) including common process models like waterfall and iterative development. The unified process model is introduced as a iterative approach used in SDLC.
The document provides an overview of system development methodologies, with a focus on structured analysis and design versus object-oriented analysis and design. It discusses the analysis, design, and implementation phases of an object-oriented systems development life cycle. In the analysis phase, it describes how use case diagrams and class diagrams are used to model object-oriented analysis using the Unified Modeling Language. It also provides guidance on identifying domain classes from problem statements by looking for noun phrases and applying subject matter expertise.
This document provides an overview of object-oriented programming (OOP) concepts including objects, classes, encapsulation, inheritance, polymorphism, and abstraction. It explains that OOP allows decomposition of programs into objects that contain both data and functions. Classes act as blueprints for objects and define their properties and behaviors.
This document provides an overview of system modeling techniques for requirements engineering, including data flow diagrams (DFDs), entity-relationship modeling, and object-oriented modeling. It discusses the benefits of modeling, provides examples of each technique, and outlines a methodology for object-oriented analysis using a library system as a case study. The key steps are identifying core classes, modeling relationships between classes, defining attributes and operations, and identifying messages passed between objects. While object-oriented modeling is useful, the document notes it is better suited for design than pure analysis and other techniques like use cases may need to be combined.
Object oriented analysis emphasizes investigating the problem domain to identify relevant objects and their relationships. The key goals are to define relevant classes and their attributes, operations, relationships, and behaviors through iterative refinement. Various analysis methods take different approaches, but generally involve use case modeling, class modeling, and behavior modeling.
The 23 gof design patterns in java ,the summaryguestebd714
The document summarizes the Gang of Four (GoF) design patterns, which are divided into three main categories: creational patterns, structural patterns, and behavioral patterns. It provides a brief description of each design pattern, including the problem it addresses and examples of when it would be used. The summary focuses on the high-level purpose and organization of the document rather than detailing each individual pattern.
The 23 gof design patterns in java ,the summaryachraf_ing
The document summarizes several design patterns categorized as creational, behavioral, and structural patterns. The creational patterns (e.g. abstract factory, builder) describe ways to create objects while hiding the instantiation logic. The behavioral patterns (e.g. chain of responsibility, command) are concerned with communication between objects. The structural patterns (e.g. adapter, bridge) focus on relationships between entities and how they can be composed. For each pattern, the document briefly outlines its purpose and examples of when it may be used.
Object-oriented analysis and design is an evolutionary development method built upon past proven concepts. The document discusses object-oriented systems development processes including use case driven analysis, the Object Modeling Technique (OMT), class diagrams, relationships between classes, and object-oriented modeling. It provides examples of class diagrams showing classes, attributes, operations, and relationships. It also explains the four views of OMT - the object model, dynamic model, functional model, and how OMT separates modeling.
The document discusses several design patterns including Singleton, Factory, Chain of Responsibility, Adapter, Strategy, Composite, and Observer patterns. It provides descriptions of each pattern including their intent, participants, relationships between participants, and examples. The Singleton pattern ensures only one instance of a class is created while the Factory pattern abstracts object creation. Chain of Responsibility passes requests between handlers in a chain until one handles it. Adapter converts one interface to another while Strategy makes behaviors interchangeable. Composite represents part-whole hierarchies and Observer notifies dependents of state changes.
The document discusses the key elements of the object model, including abstraction, encapsulation, modularity, and hierarchy. It explains that abstraction is one of the fundamental ways to cope with complexity in software design. Abstraction focuses on the essential characteristics of an object that distinguish it from other objects, from the perspective of the viewer. The object model provides a conceptual framework for object-oriented programming that is based on these elements.
The document discusses abstraction, which is a fundamental concept of object-oriented design. Abstraction involves focusing on essential characteristics of an object that distinguish it from others, separating an object's interface from its implementation. There are different types of abstractions from most to least useful: entity, action, virtual machine, and coincidental. Other key concepts discussed include contracts, invariants, exceptions, static and dynamic properties, and passive vs. active objects.
The document discusses abstraction, which is a fundamental concept of object-oriented design. Abstraction involves focusing on an object's essential characteristics and behavior while hiding implementation details. There are different types of abstractions from most useful to least useful. Effective abstractions model real-world entities and provide well-defined interfaces through contracts, preconditions, and postconditions. Both static and dynamic properties of objects must be considered.
The document discusses abstraction, which is a fundamental concept of object-oriented design. Abstraction involves focusing on an object's essential characteristics and behavior while hiding implementation details. There are different types of abstractions from most useful to least useful. Effective abstractions model real-world entities and provide well-defined interfaces through contracts, preconditions, and postconditions. Both static and dynamic properties of objects must be considered.
The document discusses the key elements of the object model, including abstraction, encapsulation, modularity, and hierarchy. It explains that abstraction is one of the fundamental ways to cope with complexity in software design. Abstraction focuses on the essential characteristics of an object that distinguish it from other objects, from the perspective of the viewer. The object model provides a conceptual framework for object-oriented programming that is based on these elements.
UML (Unified Modeling Language) is a standard modeling language used to document and visualize the design of object-oriented software systems. It was developed in the 1990s to standardize the different object-oriented modeling notations that existed. UML is based on several influential object-oriented analysis and design methodologies. It includes diagrams for modeling a system's structural and behavioral elements, and has continued to evolve with refinements and expanded applicability. Use case diagrams are one type of UML diagram that are used to define system behaviors and goals from the perspective of different user types or external entities known as actors.
UML component diagrams describe software components and their dependencies. A component represents a modular and replaceable unit with well-defined interfaces. Component diagrams show the organization and dependencies between components using interfaces, dependencies, ports, and connectors. They can show both the external view of a component's interfaces as well as its internal structure by nesting other components or classes.
Activity diagrams show the flow and sequence of activities in a system by depicting actions, decisions, and parallel processes through graphical symbols like activities, transitions, decisions, and swimlanes. They are used to model workflows, use cases, and complex methods by defining activities, states, objects, responsibilities, and connections between elements. Guidelines are provided for creating activity diagrams, such as identifying the workflow objective, pre/post-conditions, activities, states, objects, responsibilities, and evaluating for concurrency.
Object diagrams represent a snapshot of a system at a particular moment, showing the concrete instances of classes and their relationships. They capture the static view of a system to show object behaviors and relationships from a practical perspective. Unlike class diagrams which show abstract representations, object diagrams depict real-world objects and their unlimited possible instances. They are used for forward and reverse engineering, modeling object relationships and interactions, and understanding system behavior.
Sequence diagrams show the interactions between objects over time by depicting object lifelines and messages exchanged. They emphasize the time ordering of messages. To create a sequence diagram, identify participating objects and messages, lay out object lifelines across the top, and draw messages between lifelines from top to bottom based on timing. Activation boxes on lifelines indicate when objects are active. Sequence diagrams help document and understand the logical flow of a system.
State chart diagrams define the different states an object can be in during its lifetime, and how it transitions between states in response to events. They are useful for modeling reactive systems by describing the flow of control from one state to another. The key elements are initial and final states, states represented by rectangles, and transitions between states indicated by arrows. State chart diagrams are used to model the dynamic behavior and lifetime of objects in a system and identify the events that trigger state changes.
This document provides an overview of use case diagrams and use cases. It defines what a use case is, including that it captures a user's interaction with a system to achieve a goal. It describes the key components of a use case diagram, including actors, use cases, and relationships between use cases like generalization, inclusion, and extension. An example use case diagram for a money withdrawal from an ATM is presented to illustrate these concepts. Guidelines for documenting use cases with descriptions of flows, exceptions, and other details are also provided.
Unit 8 discusses software testing concepts including definitions of testing, who performs testing, test characteristics, levels of testing, and testing approaches. Unit testing focuses on individual program units while integration testing combines units. System testing evaluates a complete integrated system. Testing strategies integrate testing into a planned series of steps from requirements to deployment. Verification ensures correct development while validation confirms the product meets user needs.
This document discusses requirements analysis and design. It covers the types and characteristics of requirements, as well as the tasks involved in requirements engineering including inception, elicitation, elaboration, negotiation, specification, validation, and management. It also discusses problems that commonly occur in requirements practices and solutions through proper requirements engineering. Additionally, it outlines goals and elements of analysis modeling, including flow-oriented, scenario-based, class-based, and behavioral modeling. Finally, it discusses the purpose and tasks of design engineering in translating requirements models into design models.
Design process interaction design basicsPreeti Mishra
This document provides an introduction to interaction design basics and terms. It discusses that interaction design involves creating technology-based interventions to achieve goals within constraints. The design process has several stages and is iterative. Interaction design starts with understanding users through methods like talking to and observing them. Scenarios are rich stories used throughout design to illustrate user interactions. Basic terms in interaction design include goals, constraints, trade-offs, and the design process. Usability and user-centered design are also discussed.
The document provides an overview of design process and factors that affect user experience in interface design. It discusses various principles and heuristics to support usability, including learnability, flexibility, and robustness. The document outlines principles that affect these factors, such as predictability, consistency and dialog initiative. It also discusses guidelines for improving usability through user testing and iterative design. The document emphasizes the importance of usability and provides several heuristics and guidelines to measure and improve usability in interface design.
Design process evaluating interactive_designsPreeti Mishra
The document discusses various methods for evaluating interactive systems, including expert analysis methods like heuristic evaluation and cognitive walkthrough, as well as user-based evaluation techniques like observational methods, query techniques, and physiological monitoring. It provides details on the process for each method and considerations for when each may be most appropriate. Evaluation aims to determine a system's usability, identify design issues, compare alternatives, and observe user effects. The criteria discussed include expert analysis, user-based, and model-based approaches.
Foundations understanding users and interactionsPreeti Mishra
This document discusses qualitative user research methods. It explains that qualitative research helps understand user behavior, which is too complex to understand solely through quantitative data. Qualitative research methods include interviews, observation, and persona creation. Personas are fictional user archetypes created from interview data to represent different types of users. They are useful for product design by providing empathy for users and guiding decisions. The document provides details on creating personas and using scenarios to represent how personas would interact with a product.
This document provides an introduction to human-computer interaction (HCI). It defines HCI as a discipline concerned with studying, designing, building, and implementing interactive computing systems for human use, with a focus on usability. The document outlines various perspectives in HCI including sociology, anthropology, ergonomics, psychology, and linguistics. It also defines HCI and lists 8 guidelines for creating good HCI, such as consistency, informative feedback, and reducing memory load. The importance of good interfaces is discussed, noting they can make or break a product's acceptance. Finally, some principles and theories of user-centered design are introduced.
This document discusses the Think Pair Share activity and principles of cohesion and coupling in software design. It provides definitions and examples of different types of coupling (data, stamp, control, etc.) and levels of cohesion (functional, sequential, communicational, etc.). The key goals are to minimize coupling between modules to reduce dependencies, and maximize cohesion so elements within a module are strongly related and focused on a single task. High cohesion and low coupling lead to components that are more independent, flexible, and maintainable.
Software testing techniques document discusses various software testing methods like unit testing, integration testing, system testing, white box testing, black box testing, performance testing, stress testing, and scalability testing. It provides definitions and characteristics of each method. Some key points made in the document include that unit testing tests individual classes, integration testing tests class interactions, system testing validates functionality, and performance testing evaluates how the system performs under varying loads.
The document discusses modeling different aspects of software systems using UML diagrams. It covers modeling events using state machines, the four types of events that can be modeled in UML (signals, calls, time, and state change), modeling logical database schemas using class diagrams, modeling source code using artifact diagrams, modeling executable releases using artifact diagrams to show deployment artifacts and relationships, and modeling physical databases by defining tables for classes while considering inheritance relationships.
This document provides an introduction to object-oriented concepts and methodologies. It defines key OO terms like abstraction, encapsulation, polymorphism, and more. It also discusses object-oriented modeling techniques and popular object-oriented methodologies like Booch, RDD, OMT, and OOSE. The document aims to equip readers with an understanding of fundamental OO principles and how they are applied in analysis, design, and implementation of object-oriented systems.
This document provides an overview of functional modeling and data flow diagrams. It discusses that functional modeling gives the process perspective of object-oriented analysis and defines the functions and data flows within a system. It then describes different types of functional models including functional flow block diagrams and data flow diagrams. It provides details on how to construct functional flow block diagrams including the use of function blocks, numbering, references, flow connections, direction and gates. It also notes some potential problems with functional modeling.
Advanced control scheme of doubly fed induction generator for wind turbine us...IJECEIAES
This paper describes a speed control device for generating electrical energy on an electricity network based on the doubly fed induction generator (DFIG) used for wind power conversion systems. At first, a double-fed induction generator model was constructed. A control law is formulated to govern the flow of energy between the stator of a DFIG and the energy network using three types of controllers: proportional integral (PI), sliding mode controller (SMC) and second order sliding mode controller (SOSMC). Their different results in terms of power reference tracking, reaction to unexpected speed fluctuations, sensitivity to perturbations, and resilience against machine parameter alterations are compared. MATLAB/Simulink was used to conduct the simulations for the preceding study. Multiple simulations have shown very satisfying results, and the investigations demonstrate the efficacy and power-enhancing capabilities of the suggested control system.
Redefining brain tumor segmentation: a cutting-edge convolutional neural netw...IJECEIAES
Medical image analysis has witnessed significant advancements with deep learning techniques. In the domain of brain tumor segmentation, the ability to
precisely delineate tumor boundaries from magnetic resonance imaging (MRI)
scans holds profound implications for diagnosis. This study presents an ensemble convolutional neural network (CNN) with transfer learning, integrating
the state-of-the-art Deeplabv3+ architecture with the ResNet18 backbone. The
model is rigorously trained and evaluated, exhibiting remarkable performance
metrics, including an impressive global accuracy of 99.286%, a high-class accuracy of 82.191%, a mean intersection over union (IoU) of 79.900%, a weighted
IoU of 98.620%, and a Boundary F1 (BF) score of 83.303%. Notably, a detailed comparative analysis with existing methods showcases the superiority of
our proposed model. These findings underscore the model’s competence in precise brain tumor localization, underscoring its potential to revolutionize medical
image analysis and enhance healthcare outcomes. This research paves the way
for future exploration and optimization of advanced CNN models in medical
imaging, emphasizing addressing false positives and resource efficiency.
Null Bangalore | Pentesters Approach to AWS IAMDivyanshu
#Abstract:
- Learn more about the real-world methods for auditing AWS IAM (Identity and Access Management) as a pentester. So let us proceed with a brief discussion of IAM as well as some typical misconfigurations and their potential exploits in order to reinforce the understanding of IAM security best practices.
- Gain actionable insights into AWS IAM policies and roles, using hands on approach.
#Prerequisites:
- Basic understanding of AWS services and architecture
- Familiarity with cloud security concepts
- Experience using the AWS Management Console or AWS CLI.
- For hands on lab create account on [killercoda.com](https://killercoda.com/cloudsecurity-scenario/)
# Scenario Covered:
- Basics of IAM in AWS
- Implementing IAM Policies with Least Privilege to Manage S3 Bucket
- Objective: Create an S3 bucket with least privilege IAM policy and validate access.
- Steps:
- Create S3 bucket.
- Attach least privilege policy to IAM user.
- Validate access.
- Exploiting IAM PassRole Misconfiguration
-Allows a user to pass a specific IAM role to an AWS service (ec2), typically used for service access delegation. Then exploit PassRole Misconfiguration granting unauthorized access to sensitive resources.
- Objective: Demonstrate how a PassRole misconfiguration can grant unauthorized access.
- Steps:
- Allow user to pass IAM role to EC2.
- Exploit misconfiguration for unauthorized access.
- Access sensitive resources.
- Exploiting IAM AssumeRole Misconfiguration with Overly Permissive Role
- An overly permissive IAM role configuration can lead to privilege escalation by creating a role with administrative privileges and allow a user to assume this role.
- Objective: Show how overly permissive IAM roles can lead to privilege escalation.
- Steps:
- Create role with administrative privileges.
- Allow user to assume the role.
- Perform administrative actions.
- Differentiation between PassRole vs AssumeRole
Try at [killercoda.com](https://killercoda.com/cloudsecurity-scenario/)
DEEP LEARNING FOR SMART GRID INTRUSION DETECTION: A HYBRID CNN-LSTM-BASED MODELijaia
As digital technology becomes more deeply embedded in power systems, protecting the communication
networks of Smart Grids (SG) has emerged as a critical concern. Distributed Network Protocol 3 (DNP3)
represents a multi-tiered application layer protocol extensively utilized in Supervisory Control and Data
Acquisition (SCADA)-based smart grids to facilitate real-time data gathering and control functionalities.
Robust Intrusion Detection Systems (IDS) are necessary for early threat detection and mitigation because
of the interconnection of these networks, which makes them vulnerable to a variety of cyberattacks. To
solve this issue, this paper develops a hybrid Deep Learning (DL) model specifically designed for intrusion
detection in smart grids. The proposed approach is a combination of the Convolutional Neural Network
(CNN) and the Long-Short-Term Memory algorithms (LSTM). We employed a recent intrusion detection
dataset (DNP3), which focuses on unauthorized commands and Denial of Service (DoS) cyberattacks, to
train and test our model. The results of our experiments show that our CNN-LSTM method is much better
at finding smart grid intrusions than other deep learning algorithms used for classification. In addition,
our proposed approach improves accuracy, precision, recall, and F1 score, achieving a high detection
accuracy rate of 99.50%.
Software Engineering and Project Management - Introduction, Modeling Concepts...Prakhyath Rai
Introduction, Modeling Concepts and Class Modeling: What is Object orientation? What is OO development? OO Themes; Evidence for usefulness of OO development; OO modeling history. Modeling
as Design technique: Modeling, abstraction, The Three models. Class Modeling: Object and Class Concept, Link and associations concepts, Generalization and Inheritance, A sample class model, Navigation of class models, and UML diagrams
Building the Analysis Models: Requirement Analysis, Analysis Model Approaches, Data modeling Concepts, Object Oriented Analysis, Scenario-Based Modeling, Flow-Oriented Modeling, class Based Modeling, Creating a Behavioral Model.
Generative AI Use cases applications solutions and implementation.pdfmahaffeycheryld
Generative AI solutions encompass a range of capabilities from content creation to complex problem-solving across industries. Implementing generative AI involves identifying specific business needs, developing tailored AI models using techniques like GANs and VAEs, and integrating these models into existing workflows. Data quality and continuous model refinement are crucial for effective implementation. Businesses must also consider ethical implications and ensure transparency in AI decision-making. Generative AI's implementation aims to enhance efficiency, creativity, and innovation by leveraging autonomous generation and sophisticated learning algorithms to meet diverse business challenges.
https://www.leewayhertz.com/generative-ai-use-cases-and-applications/
AI for Legal Research with applications, toolsmahaffeycheryld
AI applications in legal research include rapid document analysis, case law review, and statute interpretation. AI-powered tools can sift through vast legal databases to find relevant precedents and citations, enhancing research accuracy and speed. They assist in legal writing by drafting and proofreading documents. Predictive analytics help foresee case outcomes based on historical data, aiding in strategic decision-making. AI also automates routine tasks like contract review and due diligence, freeing up lawyers to focus on complex legal issues. These applications make legal research more efficient, cost-effective, and accessible.
Digital Twins Computer Networking Paper Presentation.pptxaryanpankaj78
A Digital Twin in computer networking is a virtual representation of a physical network, used to simulate, analyze, and optimize network performance and reliability. It leverages real-time data to enhance network management, predict issues, and improve decision-making processes.
Embedded machine learning-based road conditions and driving behavior monitoringIJECEIAES
Car accident rates have increased in recent years, resulting in losses in human lives, properties, and other financial costs. An embedded machine learning-based system is developed to address this critical issue. The system can monitor road conditions, detect driving patterns, and identify aggressive driving behaviors. The system is based on neural networks trained on a comprehensive dataset of driving events, driving styles, and road conditions. The system effectively detects potential risks and helps mitigate the frequency and impact of accidents. The primary goal is to ensure the safety of drivers and vehicles. Collecting data involved gathering information on three key road events: normal street and normal drive, speed bumps, circular yellow speed bumps, and three aggressive driving actions: sudden start, sudden stop, and sudden entry. The gathered data is processed and analyzed using a machine learning system designed for limited power and memory devices. The developed system resulted in 91.9% accuracy, 93.6% precision, and 92% recall. The achieved inference time on an Arduino Nano 33 BLE Sense with a 32-bit CPU running at 64 MHz is 34 ms and requires 2.6 kB peak RAM and 139.9 kB program flash memory, making it suitable for resource-constrained embedded systems.
Prediction of Electrical Energy Efficiency Using Information on Consumer's Ac...PriyankaKilaniya
Energy efficiency has been important since the latter part of the last century. The main object of this survey is to determine the energy efficiency knowledge among consumers. Two separate districts in Bangladesh are selected to conduct the survey on households and showrooms about the energy and seller also. The survey uses the data to find some regression equations from which it is easy to predict energy efficiency knowledge. The data is analyzed and calculated based on five important criteria. The initial target was to find some factors that help predict a person's energy efficiency knowledge. From the survey, it is found that the energy efficiency awareness among the people of our country is very low. Relationships between household energy use behaviors are estimated using a unique dataset of about 40 households and 20 showrooms in Bangladesh's Chapainawabganj and Bagerhat districts. Knowledge of energy consumption and energy efficiency technology options is found to be associated with household use of energy conservation practices. Household characteristics also influence household energy use behavior. Younger household cohorts are more likely to adopt energy-efficient technologies and energy conservation practices and place primary importance on energy saving for environmental reasons. Education also influences attitudes toward energy conservation in Bangladesh. Low-education households indicate they primarily save electricity for the environment while high-education households indicate they are motivated by environmental concerns.
Use PyCharm for remote debugging of WSL on a Windo cf5c162d672e4e58b4dde5d797...shadow0702a
This document serves as a comprehensive step-by-step guide on how to effectively use PyCharm for remote debugging of the Windows Subsystem for Linux (WSL) on a local Windows machine. It meticulously outlines several critical steps in the process, starting with the crucial task of enabling permissions, followed by the installation and configuration of WSL.
The guide then proceeds to explain how to set up the SSH service within the WSL environment, an integral part of the process. Alongside this, it also provides detailed instructions on how to modify the inbound rules of the Windows firewall to facilitate the process, ensuring that there are no connectivity issues that could potentially hinder the debugging process.
The document further emphasizes on the importance of checking the connection between the Windows and WSL environments, providing instructions on how to ensure that the connection is optimal and ready for remote debugging.
It also offers an in-depth guide on how to configure the WSL interpreter and files within the PyCharm environment. This is essential for ensuring that the debugging process is set up correctly and that the program can be run effectively within the WSL terminal.
Additionally, the document provides guidance on how to set up breakpoints for debugging, a fundamental aspect of the debugging process which allows the developer to stop the execution of their code at certain points and inspect their program at those stages.
Finally, the document concludes by providing a link to a reference blog. This blog offers additional information and guidance on configuring the remote Python interpreter in PyCharm, providing the reader with a well-rounded understanding of the process.
2. An overview of OOSE development
activities and their products
Requirements
elicitation
Analysis
System design
problem statement
functional
model
nonfunctional
requirements
analysis
object model
dynamic
model
class diagram
use case
diagram
statechart
diagram
sequence diagram
3. An Introduction to Object Modeling
– The approach of using object modeling
during systems analysis and design is
called object-oriented analysis.
• Object-oriented analysis (OOA) techniques
are used to
– (1) study existing objects to see if they can be reused or
adapted for new uses, and to
– (2) define new or modified objects that will be combined
with existing objects into a useful business computing
application.
4. Definition : Object Modeling
– The object-oriented approach is centered
around a technique referred to as object
modeling.
• Object modeling is a technique for identifying
objects within the systems environment, and the
relationships between those objects.
5. Why do we model
• Models help us to visualize a system as it is or as we want it
to be.
• Models permit us to specify the structure or behavior of a
system.
• Models give us a template that guides us in constructing a
system.
• Models document the decisions we have made.
6. System concepts for
Object Modeling
• Object and related concepts
– What is and isn’t an Object
– Attribute, state
– Behavior/ operations
– Roles- responsibilities
– Identity
– Life span
7. System concepts for
Object Modeling
• Objet Oriented Concepts:
– Abstraction
– Encapsulation
– Inheritance
– Modularity
– Polymorphism
8. Principles of Modeling
• The choice of what models to create has a profound
influence on how a problem is attacked and how a solution is
shaped.
• Every model may be expressed at different levels of
precision.
• The best models are connected to reality.
• No single model is sufficient. Every nontrivial system is
best approached through a small set of nearly independent
models.
9. Activities during Object Modeling
Main goal: Find the important abstractions
• Steps during object modeling
1. Class identification
– Based on the fundamental assumption that we can find abstractions
2. Find the attributes
3. Find the methods
4. Find the associations between classes
• Order of steps
• Goal: get the desired abstractions
• Order of steps secondary, only a heuristic
– What happens if we find the wrong abstractions?
• We iterate and revise the model
10. Class Identification
Class identification is crucial to object-
oriented modeling
– Helps to identify the important entities of a
system
• Basic assumptions:
1. We can find the classes for a new software
system (Forward Engineering)
2. We can identify the classes in an existing
system (Reverse Engineering)
• Why can we do this?
– Philosophy, science, experimental evidence.
11. Class Identification
• Approaches
– Application domain approach
• Ask application domain experts to identify relevant
abstractions
– Syntactic approach
• Start with use cases
• Analyze the text to identify the objects
• Extract participating objects from flow of events
– Design patterns approach
• Use reusable design patterns
– Component-based approach
• Identify existing solution classes.
12. Class identification is a
Hard Problem
• One problem: Definition of the system boundary:
– Which abstractions are outside, which abstractions are
inside the system boundary?
• Actors are outside the system
• Classes/Objects are inside the system.
• An other problem: Classes/Objects are not just
found by taking a picture of a scene or domain
– The application domain has to be analyzed
– Depending on the purpose of the system different
objects might be found
• How can we identify the purpose of a system?
• Scenarios and use cases => Functional model
13. There are different
types of Objects
• Entity Objects
– Represent the persistent information tracked
by the system (Application domain objects, also
called “Business objects”)
• Boundary Objects
– Represent the interaction between the user
and the system
• Control Objects
– Represent the control tasks performed by the
system.
15. Types of Relationships
• Objects contribute to the behavior of a system by
collaborating with one another.
• The relationship between any two objects encompasses
the assumptions that each makes about the other
• two kinds of object hierarchies are of particular
interest in object-oriented analysis and design, namely:
– Links
– Aggregation
– Simple relations
16. Types of Relationships
• Objects can work together in three different
types of relationships:
• Uses(links/ Association): An object can use
another to do some work (association).
• Composition: A complex object may be composed
of several parts (aggregation, containment).
• Simple(links): Two objects may depend on each
other but don’t interact directly (weak
association)
17. Links/ Uses/ Association
• Semantics The term link derives from Rumbaugh, who
defines it as a "physical or conceptual connection between
objects" .
• An object collaborates with other objects through its links
to these objects.
• Stated another way, a link denotes the specific association
through which one object (the client) applies the services
of another object (the supplier), or through which one
object may navigate to another.
• Message passing between two objects is typically
unidirectional, although it may occasionally
• be bidirectional.
18. Objects that Use Objects
(Links/ Uses)
• Whenever one object sends a message to another object
(even if object
• Doesn’t send messages back), a uses relationship is
established them.
• Ex: A SalesInvoice uses a Customer object
• Six different
19. Techniques For Implementing A Uses/
Links/ Association Relationship
Object 1 uses object 2
1. Object 2 as Arguments
2. Creating Your Own objects 2
3. Third Party object 2
4. Combining Constructors
5. Passing an Argument
6. Creating Objects On-The-Fly
20. As argument
• Option would be to pass the object2 as an argument to
the constructor of the object1
• Rule for Using Objects
• You should use an attribute when:
– The obj needs to be directed from several different methods, or
the obj stores persistent state info between method calls.
– The obj you are going to use is used repeatedly.
– The obj is very expensive or time consuming to construct, and you
will use the obj more than once.
21. Creating Your Own objects
• A second solution is to construct the object2 in the object1
class constructor.
22. Third Party object
• It assumes that a repository of Customers
(CustomerDB) keeps track of all Customer objects
23. Combining Constructors
• Give the object1 class two constructors and use a
no-argument constructor when you want to create
a new object1.
24. Passing an Argument
• Sometimes an object may have a very short and
transitory relationship with another object.
• You may need to use an object only during the execution
of a single method.
• In that case, you might choose to have the method take
as an argument an instance of the object it uses
25. This is appropriate when:
• The obj you are going to use will be used in a single method,
and the state of that obj doesn’t need to be retained
between calls.
• The obj you have to use carries with it some immediate state
info thatmust be renewed each time the method is called.
• The obj you’re using is easily constructed outside your class.
If,however, it’s easier for you (using class) to construct the
obj from scratch(because of some special knowledge), use
the objects on-the-fly technique.
26. This is appropriate when:
• If an identical obj is constructed over and over,
or it it’s very time-consuming to construct an obj
and you need to use it more than once,
• you should use a referential attribute to hold a
reference to the obj you’ll use, rather than pass it
as an argument or create it on-the-fly
27. Creating objects
on the fly
• A second way to get an object that will be used in only a
single method is to create it inside the method itself.
• This has the advantage that
– it makes the calling method easier, and that
– the code where the object is created inside the method is
inherently more maintainable.
• This technique is called for when the using object has
special knowledge that required to create the object that
it will use
28.
29. Roles
• As a participant in a link, an object may play one of three
roles:
– Actor An object that can operate upon other objects but is
never operated upon by other objects; in some contexts, the
terms active object and actor are
interchangeable
– Server An object that never operates upon other objects; it is
only operated upon by other objects
– Agent An object that can both operate upon other objects and
be operated upon by other objects; an agent is usually created to
do some work on behalf of an actor or another agent
30. Synchronization
• Synchronization Whenever one object passes a message to
another across a link, the two objects are said to be
synchronized.
• However, in the presence of multiple threads of control,
objects require more sophisticated message passing in
order to deal with the problems of mutual exclusion that
can occur in concurrent systems.
• As we described earlier, active objects embody their own
• thread of control, and so we expect their semantics to be
guaranteed in the presence of other active objects.
31. Approach to Synchronization
• we must choose one of three approaches to
synchronization:
• Sequential :The semantics of the passive object are
guaranteed only in the presence of a single active object at
a time.
• Guarded :The semantics of the passive object are
guaranteed in the presence of multiple threads of control,
but the active clients must collaborate to achieve mutual
exclusion.
• Synchronous: The semantics of the passive object are
guaranteed in the presence of multiple threads of control,
and the supplier guarantees mutual exclusion.
32. Aggregate
• Semantics Whereas links denote peer-to-peer or
client/supplier relationships, aggregation
• denotes a whole/part hierarchy, with the ability to navigate
from the whole (also called the aggregate) to its parts (also
known as its attributes). In this sense, aggregation is a
specialized kind of association.
33. Aggregation
• Aggregation may or may not denote physical containment.
For example, an airplane is
• composed of wings, engines, landing gear, and so on: this is
a case of physical containment.
• On the other hand, the relationship between a shareholder
and her shares is an aggregation
• relationship that does not require physical containment.
34. Aggregation
• There are clear trade-offs between links and aggregation.
Aggregation is sometimes better because it encapsulates
parts as secrets of the whole.
• Links are sometimes better because they permit looser
coupling among objects.
• Intelligent engineering decisions require careful weighing
of these two factors.
• By implication, an object that is an attribute of another
has a link to its aggregate. Across this link, the aggregate
may send messages to its parts.
35. Cardinality/ Multiplicity
• No of participants in a relationships is shown by its
cardinality value
• The Multiplicity of an association indicates with how many
objects the opposing class of an object can be
instantiated.
• When this number is variable, then the bandwidth - or
minimum and maximum - is indicated 3..7 .
• If the minimum is 0, this means that the relationship is
optional (the relationship is still there, only the number of
elements is 0).
• If the minimum is equal to the maximum, only one value is
written.
36. Association – example
• In a home theatre system,
– A TV object has an association with a
VCR object
• It may receive a signal from the VCR
– VCR may be associated with remote
• It may receive a signal (command) to
record
VCR TV
1
Connected to
1
Remote
1
commands
1
39. left right example
1 1 one-to-one person <-> weight
0..1 1
optional on one
side one-to-one
date of death <->
person
0..* or * 0..* or *
optional on both
sides many-to-
many
person <-> book
1 1..* one-to-many
Birth Place <->
person
one (1): Indicates that exactly one entity type instance exists at the
association end.
zero or one (0..1): Indicates that zero or one entity type instances exist
at the association end.
many (*): Indicates that zero, one, or more entity type instances exist at
the association end.
40. • A teacher teaches 1 to 3 courses
(subjects)
• Each course is taught by only one teacher.
• A student can take between 1 to 5 courses.
• A course can have 10 to 300 students.
Association – Multiplicity
Teacher Course
teaches 1..31
Students
takes
1..5
10..300
41. Try them
• 1. These relationships are read in the following way:
– An event has a seating plan.
– A seating plan is allocated to a venue.
• 2. A seating plan has unlimited capacity, but usually only
one seat.
• A seat belongs to one specific seating plan.
• Every seating plan belongs to one specific event.
• An event may contain an unlimited number of seating plans.
• The seating plan can also be assigned to another event
(Aggregation), but must in any case always have one event.
• The seat is part of a seating plan; this relationship can
never be changed (Composition).
46. Class
• A class is a set of objects that share a common structure
and a common behaviour.
• A single object is simply an instance of a class.
47. What isn't a class?
• An object is not a class, although, curiously
• class may be an object. Objects that share no common
structure and behaviour cannot be grouped in a class
because, by definition, they are unrelated except by their
general nature as objects.
48. Template for object creation:
Instantiated into objects
An abstract data type (ADT)
Examples: Employees, Books, etc.
Sometimes not intended to produce
instances:
Abstract classes
Class
49. UML Class Representation
• A class represents a set of objects having similar
attributes, operations, relationships and behavior.
Window
size: Size
visibility: boolean
display()
hide()
Class Name
Inline Attributes
Operations
A class can
implicitly
have a few
association
attributes
51. Terms and Concepts
• A class is a description of a set of objects that share
the same attributes, operations, relationships, and
semantics.
• Graphically, a class is rendered as a rectangle.
52. Class: Name
• Every class must have a name that distinguishes it from
other classes.
• A name is a textual string.
• That name alone is known as a simple name; a path name is
the class name prefixed by the name of the package in
which that class lives.
• A class may be drawn showing only its name
53. Class: Name
• A class name may be text consisting of any number of
letters, numbers, and certain punctuation marks (except
for marks such as the colon, which is used to separate a
class name and the name of its enclosing package)
• Typically, you capitalize the first letter of every word in a
class name, as in Customer or TemperatureSensor.
54. Attribute
• Attributes are related to the semantics of aggregation.
• An attribute is a named property of a class that describes
a range of values that instances of the property may hold.
A class may have any number of attributes or no attributes
at all.
• An attribute represents some property of the thing you
are modeling that is shared by all objects of that class.
• An attribute is therefore an abstraction of the kind of
data or state an object of the class might encompass.
• At a given moment, an object of a class will have specific
values for every one of its class's attributes.
• Graphically, attributes are listed in a compartment just
below the class name.
55. • An attribute name may be text, just like a class
name. In practice, an attribute name is
• a short noun or noun phrase that represents some
property of its enclosing class.
• Typically, you capitalize the first letter of every
word in an attribute name except the
• first letter, as in name or loadBearing.
56.
57. Operation
• An operation is the implementation of a service that can
be requested from any object of the class to affect
behavior.
• A class may have any number of operations or no
operations at all.
• Often (but not always), invoking an operation on an
object changes the object's data or state.
• Graphically, operations are listed in a compartment just
below the class attributes.
• Operations may be drawn showing only their names,
58.
59. Operation
• You can specify an operation by stating its signature,
covering the name, type, and default value of all
parameters and (in the case of functions) a return type,
60. Responsibility
• Responsibility is a contract or an obligation of a class.
When you create a class,
• At a more abstract level, these corresponding attributes
and operations are just the features by which the class's
responsibilities are carried out.
• Graphically, responsibilities can be drawn in a separate
compartment at the bottom of the class icon
62. Other Features
• Sometimes, however, you'll need to visualize or specify
other features, such as the visibility of individual
attributes and operations;
• language-specific features of an operation,
• such as whether it is polymorphic or constant; or even the
exceptions that objects of the class might produce or
handle.
• These and many other features can be expressed in the
UML, but they are treated as advanced concepts
63. Modeling Techniques
• Modeling vocabulary of system
• Modeling the Distribution of Responsibilities in a System
• Modeling Non-software Things
• Modeling Primitive Types
64. Hints and Tips
• When you model classes in the UML, remember that
every class should map to some tangible or conceptual
abstraction in the domain of the end user or the
implementer.
• A well-structured class Provides a crisp abstraction of
something drawn from the vocabulary of the problem
domain or the solution domain.
• Embodies a small, well-defined set of responsibilities and
carries them all out very well.
65. Hints and Tips
• Provides a clear separation of the abstraction's
specification and its implementation.
• Is understandable and simple yet extensible and
adaptable.
• Show only those properties of the class that are
important to understanding the abstraction in its
context.
• Organize long lists of attributes and operations
by grouping them according to their category.
• Show related classes in the same class diagrams.
66. Relationships
• Relationships provide a pathway for communication
between objects
• Sequence and/or collaboration diagrams are
examined to determine what links between objects
need to exist to accomplish the behavior -- if two
objects need to “talk” there must be a link between
them
68. Relationships: Defined
• An association is a bi-directional connection between
classes
– An association is shown as a line connecting the related classes
• An aggregation is a stronger form of relationship where the
relationship is between a whole and its parts
– An aggregation is shown as a line connecting the related classes with a diamond next
to the class representing the whole
• A dependency relationship is a weaker form of relationship
showing a relationship between a client and a supplier where
the client does not have semantic knowledge of the supplier.
– A dependency is shown as a dashed line pointing from the client to the supplier
69. Generalization
(Inheritance)
• A generalization is a relationship between a more
general and a more specific element
– Inheritance is the main property of generalization-
specialization relationships defined between a superclass
and its subclasses
– Common attributes, operations, and/or relationships are
shown at the highest applicable level in the hierarchy
• Realization is a relationship defined between a type
and its implementation classes
70. Relationships: Notation• Association
• Dependency
• Aggregation
• Generalization
• Realization
type Implementation
class
Sub
clas
s
Superclass
AggregatePart
SupplierClient name