This document provides an overview of object-oriented programming concepts in Java including objects, classes, inheritance, polymorphism, and exceptions. It discusses how objects interact and have state that can be changed by sending messages. A class defines the common attributes and behaviors of objects and serves as a blueprint for creating objects. Inheritance allows classes to extend existing classes, reusing and specializing their behavior and state. When errors occur, exceptions are thrown which launch a separate control flow to handle the error instead of crashing the program.
Introduction to OOPS : Problems in procedure oriented approach, Features of Object Oriented
Programming System, Object creation, Initializing the instance variable, Constructors.
This document discusses object-oriented programming concepts like abstraction, encapsulation, constructors, and destructors in C++. It defines abstraction as hiding unnecessary details from the user to simplify complexity. Encapsulation refers to binding data with the methods that operate on the data. Constructors are special member functions that are called automatically when an object is created to initialize it. Destructors are called when an object is destroyed to perform cleanup. The document also provides examples of implementing these concepts in C++ code.
This document discusses constructors and destructors in C++. It explains that constructors initialize objects when they are created and prevent data members from having garbage values, while destructors destroy objects before they go out of scope. The document covers parameterized and copy constructors, constructor overloading, default constructor arguments, and how constructors and destructors are automatically called by the compiler. It also discusses dynamically initializing data members using constructors with pointer arguments.
This document provides an overview of object-oriented programming concepts including abstraction, encapsulation, classes, objects, methods, constructors, inheritance, polymorphism, and interfaces. It explains that classes act as blueprints for objects, describing their data and behaviors. Objects are instances of classes that have state stored in attributes and behaviors defined by methods. Key features of OOP like inheritance, encapsulation, and polymorphism are discussed at a high level.
Programming II hiding, and replacing members, Serialization, Generics, Linq ExceptionType
enum You will implement this enum in Visual Studio. There are seven members: Assignment 4 -
Implementing a Banking Application Due: See course shell for due date and time Check with
you professor to see if you are permitted to work as a group. The members are self-explanatory.
AccountType enum You will implement this enum in Visual Studio. There are three members:
The application is by far the most complex system that you have attempted so far. It consists of
eleven classes, two structs, one interface and two enums coupled in varying degrees of tightness.
The Bank class is the main driver of the application. It has collection of Accounts and Person
that is initialize appropriately in the static constructor. You will implement the entire system in
Visual Studio. A short description of each type with their members is given below. You are
advised to implement each type in the order that they are described. No method should have a
Console. WriteLine() unless you are explicitly told to output something on the console. Each
type must be in separate files.
Assignment 4, Winter 2022 Assignment 4, Winter 2022 hiding, and replacing members,
Serialization, Generics, ling Uses - Inheritance, Interfaces, Exceptions, EventHandlers,
Collections Operator overloading, Utils class hiding, and replacing members, Serialization,
Generics, Ling [The implementation for this class is given in the appendix. Create a class called
UtIs and copy and 1. Time - this public class variable is of type Day Time. It adds a random
value to the internal field_time and then returns it. past the statements into the appropriate part of
the file] 2. Now - this public class variable is of type Day Time. It adds zero to the internal
field_time You will implement the Utils class in Visual Studio. This class is comprised of three
fields and and then returns it. provides two static properties. It simulates the passage of time.
Each time the Time property is Methods: accessed, it increases the internal field by a random
amount. It is used to time stamped all banking There are no explicitly defined methods. You do
not have to code this class. Just copy the code statements from the appendix of this A short
description of each dass member is given below: document. Properties: There are three
properties. 1. _time - this private class variable is of type DayTime that store the time of this
object. It is initialized (with argument 1_648_600_800 ) at declaration. It is mutated (changed)
whenever either of the properties is accessed. 2. random - this private class variable is of type
Random storing the time of this object. It is initialized (with argument 1_848_800_800) at
declaration. It is mutated (changed) whenever elther of the properties is accessed. 3.
ACCOUNT_TYPE - this private class variable is of type Dictionary. It serves as a lookup table
to match an account type with a particular prefix, It is i.
The document discusses arrays and functions in C programming. It covers:
1) Declaring, initializing, and using one-dimensional and multi-dimensional arrays. Operations like sorting, searching and matrix operations are demonstrated.
2) The basics of functions including defining functions with and without arguments and return values. Passing arrays as arguments to functions is also covered.
3) The anatomy of a function including declarations, definitions, and invocations is explained.
The Ring programming language version 1.5.2 book - Part 69 of 181Mahmoud Samir Fayed
This document provides an overview of scope rules and how Ring determines where to find variables in code. It discusses the three scopes - global, object, and local. When looking for a variable, Ring will first search the local scope, then the object scope, and finally the global scope. It also covers how Ring handles defining new variables versus using existing ones, potential conflicts between global and object variables, and some solutions to those conflicts.
The document discusses design patterns used in object-oriented programming. It describes common design patterns like factory method, singleton, observer, and adapter patterns. It also discusses principles for assigning responsibilities to objects like high cohesion and low coupling. The document provides examples of applying these patterns and principles to design software objects and systems.
Introduction to OOPS : Problems in procedure oriented approach, Features of Object Oriented
Programming System, Object creation, Initializing the instance variable, Constructors.
This document discusses object-oriented programming concepts like abstraction, encapsulation, constructors, and destructors in C++. It defines abstraction as hiding unnecessary details from the user to simplify complexity. Encapsulation refers to binding data with the methods that operate on the data. Constructors are special member functions that are called automatically when an object is created to initialize it. Destructors are called when an object is destroyed to perform cleanup. The document also provides examples of implementing these concepts in C++ code.
This document discusses constructors and destructors in C++. It explains that constructors initialize objects when they are created and prevent data members from having garbage values, while destructors destroy objects before they go out of scope. The document covers parameterized and copy constructors, constructor overloading, default constructor arguments, and how constructors and destructors are automatically called by the compiler. It also discusses dynamically initializing data members using constructors with pointer arguments.
This document provides an overview of object-oriented programming concepts including abstraction, encapsulation, classes, objects, methods, constructors, inheritance, polymorphism, and interfaces. It explains that classes act as blueprints for objects, describing their data and behaviors. Objects are instances of classes that have state stored in attributes and behaviors defined by methods. Key features of OOP like inheritance, encapsulation, and polymorphism are discussed at a high level.
Programming II hiding, and replacing members, Serialization, Generics, Linq ExceptionType
enum You will implement this enum in Visual Studio. There are seven members: Assignment 4 -
Implementing a Banking Application Due: See course shell for due date and time Check with
you professor to see if you are permitted to work as a group. The members are self-explanatory.
AccountType enum You will implement this enum in Visual Studio. There are three members:
The application is by far the most complex system that you have attempted so far. It consists of
eleven classes, two structs, one interface and two enums coupled in varying degrees of tightness.
The Bank class is the main driver of the application. It has collection of Accounts and Person
that is initialize appropriately in the static constructor. You will implement the entire system in
Visual Studio. A short description of each type with their members is given below. You are
advised to implement each type in the order that they are described. No method should have a
Console. WriteLine() unless you are explicitly told to output something on the console. Each
type must be in separate files.
Assignment 4, Winter 2022 Assignment 4, Winter 2022 hiding, and replacing members,
Serialization, Generics, ling Uses - Inheritance, Interfaces, Exceptions, EventHandlers,
Collections Operator overloading, Utils class hiding, and replacing members, Serialization,
Generics, Ling [The implementation for this class is given in the appendix. Create a class called
UtIs and copy and 1. Time - this public class variable is of type Day Time. It adds a random
value to the internal field_time and then returns it. past the statements into the appropriate part of
the file] 2. Now - this public class variable is of type Day Time. It adds zero to the internal
field_time You will implement the Utils class in Visual Studio. This class is comprised of three
fields and and then returns it. provides two static properties. It simulates the passage of time.
Each time the Time property is Methods: accessed, it increases the internal field by a random
amount. It is used to time stamped all banking There are no explicitly defined methods. You do
not have to code this class. Just copy the code statements from the appendix of this A short
description of each dass member is given below: document. Properties: There are three
properties. 1. _time - this private class variable is of type DayTime that store the time of this
object. It is initialized (with argument 1_648_600_800 ) at declaration. It is mutated (changed)
whenever either of the properties is accessed. 2. random - this private class variable is of type
Random storing the time of this object. It is initialized (with argument 1_848_800_800) at
declaration. It is mutated (changed) whenever elther of the properties is accessed. 3.
ACCOUNT_TYPE - this private class variable is of type Dictionary. It serves as a lookup table
to match an account type with a particular prefix, It is i.
The document discusses arrays and functions in C programming. It covers:
1) Declaring, initializing, and using one-dimensional and multi-dimensional arrays. Operations like sorting, searching and matrix operations are demonstrated.
2) The basics of functions including defining functions with and without arguments and return values. Passing arrays as arguments to functions is also covered.
3) The anatomy of a function including declarations, definitions, and invocations is explained.
The Ring programming language version 1.5.2 book - Part 69 of 181Mahmoud Samir Fayed
This document provides an overview of scope rules and how Ring determines where to find variables in code. It discusses the three scopes - global, object, and local. When looking for a variable, Ring will first search the local scope, then the object scope, and finally the global scope. It also covers how Ring handles defining new variables versus using existing ones, potential conflicts between global and object variables, and some solutions to those conflicts.
The document discusses design patterns used in object-oriented programming. It describes common design patterns like factory method, singleton, observer, and adapter patterns. It also discusses principles for assigning responsibilities to objects like high cohesion and low coupling. The document provides examples of applying these patterns and principles to design software objects and systems.
Programming approaches include procedural and object-oriented. The procedural approach breaks problems into smaller parts and solves each part separately. The object-oriented approach views problems as collections of real-world objects and their relationships.
Object-oriented programming terms include object, class, attribute, method, abstraction, inheritance, encapsulation, and polymorphism. Classes define common attributes and behaviors for objects. Inheritance allows classes to extend and generalize behaviors. Encapsulation hides unnecessary details from users. Polymorphism allows objects to behave differently in different contexts.
The document provides an introduction to design patterns developed by the Gang of Four (GoF). It discusses several common design patterns in JavaScript like the constructor pattern, module pattern, singleton pattern, observer pattern, mediator pattern, prototype pattern, command pattern, facade pattern, and mixin pattern. For each pattern, it explains the problem it addresses, provides an example implementation, and notes advantages and disadvantages of the pattern. The overall document serves as a high-level overview of fundamental design patterns and their usage in JavaScript applications.
The document discusses key concepts of classes and objects in C# including defining classes, adding variables and methods, member access modifiers, creating objects, constructors, static members, private constructors, and indexers. It defines classes as user defined data types that can encapsulate data as fields and functions as methods. Objects are instances of classes that allow data and methods to be accessed. Constructors initialize objects, while static members are associated with the class rather than individual objects.
This document discusses static data members in C++. It explains that a static data member is shared among all objects of a class and is defined with the static keyword. Only one variable is created in memory even if there are multiple class objects. It is visible only within the class and persists for the lifetime of the program. The document provides examples of declaring and defining static data members separately, and using a static member to assign unique roll numbers to student objects.
Understanding Large Social Networks | IRE Major Project | Team 57 Raj Patel
This document summarizes an undergraduate project to build a model that can efficiently represent nodes in large social networks as low-dimensional vectors. The project uses the LINE algorithm from the baseline paper as a starting point. Specifically, the project implements LINE's first-order and second-order proximity models in Torch and combines the learned embeddings, unlike the baseline paper which trains the models independently. The project aims to represent over 10,000 nodes from the BlogCatalog dataset within a scalable neural network model written in Lua using the Torch framework.
The document discusses static data members in C++. It explains that a static data member is shared among all objects of a class and is defined with the static keyword. Only one variable is created in memory even if there are multiple objects. It is visible only within the class and persists for the lifetime of the program. The document provides examples of declaring and defining static data members separately, and using them to assign unique roll numbers to student objects.
This document discusses objects and classes in object-oriented programming. It defines an object as a bundle of related state and behavior that models real-world entities. A class is a blueprint or prototype from which individual objects are created, and defines common properties and methods. The document provides examples of modeling real-world objects like a dog in code by defining their states as variables and behaviors as methods. It discusses the advantages of using classes like modularity, information hiding, and code reuse. Finally, it covers key concepts of declaring classes, creating objects using constructors, defining variables, and accessing object properties and methods.
This document summarizes features introduced in C# 2, including delegates, anonymous methods, and delegate variance. Delegates allow passing methods as arguments and are used for events. C# 2 simplified delegate instantiation and introduced anonymous methods, which define inline delegate code without a named method. Underneath, anonymous methods use compiler-generated classes to capture outer scope variables. Delegate variance allows compatibility between delegate types and instances if their return and parameter types are related through inheritance.
This document discusses object-oriented programming concepts in Java such as classes, objects, inheritance, encapsulation, and polymorphism. It provides examples of defining classes with variables, methods, and constructors. It also covers creating and initializing objects, accessing instance variables and methods, and the different ways to create objects like using the new keyword, factory methods, and anonymous objects. The document also discusses strings, arrays, and core Java class libraries.
This document discusses abstract data types and encapsulation. It explains that abstract data types define a set of objects, operations on those objects, and encapsulate them so the user cannot directly access the hidden data. Encapsulation through subprograms and type definitions is described. Different approaches to static and dynamic storage management like stacks, heaps, and garbage collection are also summarized.
The document provides definitions and explanations of various object-oriented programming concepts in Delphi such as classes, objects, visibility of class members, inheritance, abstract classes, interfaces, constructors, virtual functions, polymorphism, late binding, encapsulation, properties, exceptions handling, and runtime type information (RTTI). It discusses these concepts through questions and answers. Key points covered include the relationship between classes and objects, differences between visibility levels of class members, how inheritance allows the creation of subclasses, rules around abstract classes and methods, limitations of interfaces, how to define and overload constructors and functions, use of virtual functions and polymorphism, and how RTTI is used.
Unit testing allows developers to test individual modules of an application to check for functional correctness. In Xcode, a unit test target can be created for an existing project to write and run unit tests. Unit tests should be independent, fast, and isolated. Dependency injection techniques like constructor injection and property injection allow injecting mock objects to test asynchronous code. Test doubles like stubs and mocks can fake object interactions and behavior to isolate the code being tested.
The document discusses the benefits of object-oriented programming (OOP). It states that OOP offers several benefits to programmers and users, including greater productivity, higher quality software, and lower maintenance costs. It then lists 25 specific advantages of OOP such as code reusability through inheritance, modularity through pre-defined classes, data hiding for security, and easier mapping of real-world problems to code.
This document provides an overview of object-oriented programming concepts in Java including two programming paradigms, OOP principles like encapsulation, polymorphism, abstraction and inheritance. It discusses classes, objects, and reference variables in Java. Key points covered are how classes act as blueprints for objects, the difference between objects and reference variables, and how methods can be called on objects.
The document summarizes a student project to build a model that can efficiently represent nodes in large social networks as low-dimensional vectors. The model is based on the LINE algorithm presented in the baseline paper. The students implement both first-order and second-order proximity models in Torch, using the same node representations for both. Their model achieves F1 scores between 39-42% on the BlogCatalog dataset. The project took 5 weeks and challenges included understanding the baseline paper's mathematics and debugging neural networks in Lua.
Understanding Large Social Networks | IRE Major Project | Team 57 | LINERaj Patel
The document summarizes a student project to build a model that can efficiently represent nodes in large social networks as low-dimensional vectors. The model is based on the LINE paper, which learns embeddings by optimizing for first-order and second-order proximity. For their project, the students implemented the LINE approach in Torch, using the same node representations for both proximities and evaluating on the BlogCatalog dataset. Their model achieved F1 scores between 39-41% for node classification.
The document discusses key concepts of object-oriented programming using C++ including defining classes, encapsulation, static vs non-static members, and polymorphism. A class defines a category of objects by grouping related data and functions. Classes encapsulate data by hiding implementation details and exposing an interface. Static members are shared across all objects while non-static members are unique to each object instance. Polymorphism allows the same operation to behave differently based on the object type.
Colour Sensor Based Object Sorting RobotIRJET Journal
This document describes a color sensor based object sorting robot. The robot uses color sensors to detect the color of objects passing on a conveyor belt. Based on the detected color, a robotic arm then picks up the object and places it in the corresponding colored bin location. The system aims to automate the sorting of colored objects, reducing labor costs and improving efficiency compared to manual sorting. Key components include a microcontroller, DC motors to control the conveyor and robotic arm, and color sensors to identify the object color and guide the arm to the proper drop-off location. The system provides an automatic solution for sorting tasks in manufacturing facilities and other industries.
Colour sensor based object sorting robot @1000KV Technologies 90308448771000kv technologies
This document describes a color sensor based object sorting robot. The robot uses color sensors to detect the color of objects passing on a conveyor belt. Based on the detected color, a robotic arm then picks up the object and places it in the corresponding colored bin location. The system aims to automate the sorting of colored objects, reducing labor costs and improving efficiency compared to manual sorting. Key components include a microcontroller, DC motors to drive the conveyor and robotic arm, and color sensors to identify the object color and guide the arm to the proper drop-off location. The system provides an automatic solution for sorting tasks in manufacturing facilities and other industries.
Let's Integrate MuleSoft RPA, COMPOSER, APM with AWS IDP along with Slackshyamraj55
Discover the seamless integration of RPA (Robotic Process Automation), COMPOSER, and APM with AWS IDP enhanced with Slack notifications. Explore how these technologies converge to streamline workflows, optimize performance, and ensure secure access, all while leveraging the power of AWS IDP and real-time communication via Slack notifications.
Sudheer Mechineni, Head of Application Frameworks, Standard Chartered Bank
Discover how Standard Chartered Bank harnessed the power of Neo4j to transform complex data access challenges into a dynamic, scalable graph database solution. This keynote will cover their journey from initial adoption to deploying a fully automated, enterprise-grade causal cluster, highlighting key strategies for modelling organisational changes and ensuring robust disaster recovery. Learn how these innovations have not only enhanced Standard Chartered Bank’s data infrastructure but also positioned them as pioneers in the banking sector’s adoption of graph technology.
Programming approaches include procedural and object-oriented. The procedural approach breaks problems into smaller parts and solves each part separately. The object-oriented approach views problems as collections of real-world objects and their relationships.
Object-oriented programming terms include object, class, attribute, method, abstraction, inheritance, encapsulation, and polymorphism. Classes define common attributes and behaviors for objects. Inheritance allows classes to extend and generalize behaviors. Encapsulation hides unnecessary details from users. Polymorphism allows objects to behave differently in different contexts.
The document provides an introduction to design patterns developed by the Gang of Four (GoF). It discusses several common design patterns in JavaScript like the constructor pattern, module pattern, singleton pattern, observer pattern, mediator pattern, prototype pattern, command pattern, facade pattern, and mixin pattern. For each pattern, it explains the problem it addresses, provides an example implementation, and notes advantages and disadvantages of the pattern. The overall document serves as a high-level overview of fundamental design patterns and their usage in JavaScript applications.
The document discusses key concepts of classes and objects in C# including defining classes, adding variables and methods, member access modifiers, creating objects, constructors, static members, private constructors, and indexers. It defines classes as user defined data types that can encapsulate data as fields and functions as methods. Objects are instances of classes that allow data and methods to be accessed. Constructors initialize objects, while static members are associated with the class rather than individual objects.
This document discusses static data members in C++. It explains that a static data member is shared among all objects of a class and is defined with the static keyword. Only one variable is created in memory even if there are multiple class objects. It is visible only within the class and persists for the lifetime of the program. The document provides examples of declaring and defining static data members separately, and using a static member to assign unique roll numbers to student objects.
Understanding Large Social Networks | IRE Major Project | Team 57 Raj Patel
This document summarizes an undergraduate project to build a model that can efficiently represent nodes in large social networks as low-dimensional vectors. The project uses the LINE algorithm from the baseline paper as a starting point. Specifically, the project implements LINE's first-order and second-order proximity models in Torch and combines the learned embeddings, unlike the baseline paper which trains the models independently. The project aims to represent over 10,000 nodes from the BlogCatalog dataset within a scalable neural network model written in Lua using the Torch framework.
The document discusses static data members in C++. It explains that a static data member is shared among all objects of a class and is defined with the static keyword. Only one variable is created in memory even if there are multiple objects. It is visible only within the class and persists for the lifetime of the program. The document provides examples of declaring and defining static data members separately, and using them to assign unique roll numbers to student objects.
This document discusses objects and classes in object-oriented programming. It defines an object as a bundle of related state and behavior that models real-world entities. A class is a blueprint or prototype from which individual objects are created, and defines common properties and methods. The document provides examples of modeling real-world objects like a dog in code by defining their states as variables and behaviors as methods. It discusses the advantages of using classes like modularity, information hiding, and code reuse. Finally, it covers key concepts of declaring classes, creating objects using constructors, defining variables, and accessing object properties and methods.
This document summarizes features introduced in C# 2, including delegates, anonymous methods, and delegate variance. Delegates allow passing methods as arguments and are used for events. C# 2 simplified delegate instantiation and introduced anonymous methods, which define inline delegate code without a named method. Underneath, anonymous methods use compiler-generated classes to capture outer scope variables. Delegate variance allows compatibility between delegate types and instances if their return and parameter types are related through inheritance.
This document discusses object-oriented programming concepts in Java such as classes, objects, inheritance, encapsulation, and polymorphism. It provides examples of defining classes with variables, methods, and constructors. It also covers creating and initializing objects, accessing instance variables and methods, and the different ways to create objects like using the new keyword, factory methods, and anonymous objects. The document also discusses strings, arrays, and core Java class libraries.
This document discusses abstract data types and encapsulation. It explains that abstract data types define a set of objects, operations on those objects, and encapsulate them so the user cannot directly access the hidden data. Encapsulation through subprograms and type definitions is described. Different approaches to static and dynamic storage management like stacks, heaps, and garbage collection are also summarized.
The document provides definitions and explanations of various object-oriented programming concepts in Delphi such as classes, objects, visibility of class members, inheritance, abstract classes, interfaces, constructors, virtual functions, polymorphism, late binding, encapsulation, properties, exceptions handling, and runtime type information (RTTI). It discusses these concepts through questions and answers. Key points covered include the relationship between classes and objects, differences between visibility levels of class members, how inheritance allows the creation of subclasses, rules around abstract classes and methods, limitations of interfaces, how to define and overload constructors and functions, use of virtual functions and polymorphism, and how RTTI is used.
Unit testing allows developers to test individual modules of an application to check for functional correctness. In Xcode, a unit test target can be created for an existing project to write and run unit tests. Unit tests should be independent, fast, and isolated. Dependency injection techniques like constructor injection and property injection allow injecting mock objects to test asynchronous code. Test doubles like stubs and mocks can fake object interactions and behavior to isolate the code being tested.
The document discusses the benefits of object-oriented programming (OOP). It states that OOP offers several benefits to programmers and users, including greater productivity, higher quality software, and lower maintenance costs. It then lists 25 specific advantages of OOP such as code reusability through inheritance, modularity through pre-defined classes, data hiding for security, and easier mapping of real-world problems to code.
This document provides an overview of object-oriented programming concepts in Java including two programming paradigms, OOP principles like encapsulation, polymorphism, abstraction and inheritance. It discusses classes, objects, and reference variables in Java. Key points covered are how classes act as blueprints for objects, the difference between objects and reference variables, and how methods can be called on objects.
The document summarizes a student project to build a model that can efficiently represent nodes in large social networks as low-dimensional vectors. The model is based on the LINE algorithm presented in the baseline paper. The students implement both first-order and second-order proximity models in Torch, using the same node representations for both. Their model achieves F1 scores between 39-42% on the BlogCatalog dataset. The project took 5 weeks and challenges included understanding the baseline paper's mathematics and debugging neural networks in Lua.
Understanding Large Social Networks | IRE Major Project | Team 57 | LINERaj Patel
The document summarizes a student project to build a model that can efficiently represent nodes in large social networks as low-dimensional vectors. The model is based on the LINE paper, which learns embeddings by optimizing for first-order and second-order proximity. For their project, the students implemented the LINE approach in Torch, using the same node representations for both proximities and evaluating on the BlogCatalog dataset. Their model achieved F1 scores between 39-41% for node classification.
The document discusses key concepts of object-oriented programming using C++ including defining classes, encapsulation, static vs non-static members, and polymorphism. A class defines a category of objects by grouping related data and functions. Classes encapsulate data by hiding implementation details and exposing an interface. Static members are shared across all objects while non-static members are unique to each object instance. Polymorphism allows the same operation to behave differently based on the object type.
Colour Sensor Based Object Sorting RobotIRJET Journal
This document describes a color sensor based object sorting robot. The robot uses color sensors to detect the color of objects passing on a conveyor belt. Based on the detected color, a robotic arm then picks up the object and places it in the corresponding colored bin location. The system aims to automate the sorting of colored objects, reducing labor costs and improving efficiency compared to manual sorting. Key components include a microcontroller, DC motors to control the conveyor and robotic arm, and color sensors to identify the object color and guide the arm to the proper drop-off location. The system provides an automatic solution for sorting tasks in manufacturing facilities and other industries.
Colour sensor based object sorting robot @1000KV Technologies 90308448771000kv technologies
This document describes a color sensor based object sorting robot. The robot uses color sensors to detect the color of objects passing on a conveyor belt. Based on the detected color, a robotic arm then picks up the object and places it in the corresponding colored bin location. The system aims to automate the sorting of colored objects, reducing labor costs and improving efficiency compared to manual sorting. Key components include a microcontroller, DC motors to drive the conveyor and robotic arm, and color sensors to identify the object color and guide the arm to the proper drop-off location. The system provides an automatic solution for sorting tasks in manufacturing facilities and other industries.
Let's Integrate MuleSoft RPA, COMPOSER, APM with AWS IDP along with Slackshyamraj55
Discover the seamless integration of RPA (Robotic Process Automation), COMPOSER, and APM with AWS IDP enhanced with Slack notifications. Explore how these technologies converge to streamline workflows, optimize performance, and ensure secure access, all while leveraging the power of AWS IDP and real-time communication via Slack notifications.
Sudheer Mechineni, Head of Application Frameworks, Standard Chartered Bank
Discover how Standard Chartered Bank harnessed the power of Neo4j to transform complex data access challenges into a dynamic, scalable graph database solution. This keynote will cover their journey from initial adoption to deploying a fully automated, enterprise-grade causal cluster, highlighting key strategies for modelling organisational changes and ensuring robust disaster recovery. Learn how these innovations have not only enhanced Standard Chartered Bank’s data infrastructure but also positioned them as pioneers in the banking sector’s adoption of graph technology.
Full-RAG: A modern architecture for hyper-personalizationZilliz
Mike Del Balso, CEO & Co-Founder at Tecton, presents "Full RAG," a novel approach to AI recommendation systems, aiming to push beyond the limitations of traditional models through a deep integration of contextual insights and real-time data, leveraging the Retrieval-Augmented Generation architecture. This talk will outline Full RAG's potential to significantly enhance personalization, address engineering challenges such as data management and model training, and introduce data enrichment with reranking as a key solution. Attendees will gain crucial insights into the importance of hyperpersonalization in AI, the capabilities of Full RAG for advanced personalization, and strategies for managing complex data integrations for deploying cutting-edge AI solutions.
GraphSummit Singapore | The Future of Agility: Supercharging Digital Transfor...Neo4j
Leonard Jayamohan, Partner & Generative AI Lead, Deloitte
This keynote will reveal how Deloitte leverages Neo4j’s graph power for groundbreaking digital twin solutions, achieving a staggering 100x performance boost. Discover the essential role knowledge graphs play in successful generative AI implementations. Plus, get an exclusive look at an innovative Neo4j + Generative AI solution Deloitte is developing in-house.
Dr. Sean Tan, Head of Data Science, Changi Airport Group
Discover how Changi Airport Group (CAG) leverages graph technologies and generative AI to revolutionize their search capabilities. This session delves into the unique search needs of CAG’s diverse passengers and customers, showcasing how graph data structures enhance the accuracy and relevance of AI-generated search results, mitigating the risk of “hallucinations” and improving the overall customer journey.
HCL Notes and Domino License Cost Reduction in the World of DLAUpanagenda
Webinar Recording: https://www.panagenda.com/webinars/hcl-notes-and-domino-license-cost-reduction-in-the-world-of-dlau/
The introduction of DLAU and the CCB & CCX licensing model caused quite a stir in the HCL community. As a Notes and Domino customer, you may have faced challenges with unexpected user counts and license costs. You probably have questions on how this new licensing approach works and how to benefit from it. Most importantly, you likely have budget constraints and want to save money where possible. Don’t worry, we can help with all of this!
We’ll show you how to fix common misconfigurations that cause higher-than-expected user counts, and how to identify accounts which you can deactivate to save money. There are also frequent patterns that can cause unnecessary cost, like using a person document instead of a mail-in for shared mailboxes. We’ll provide examples and solutions for those as well. And naturally we’ll explain the new licensing model.
Join HCL Ambassador Marc Thomas in this webinar with a special guest appearance from Franz Walder. It will give you the tools and know-how to stay on top of what is going on with Domino licensing. You will be able lower your cost through an optimized configuration and keep it low going forward.
These topics will be covered
- Reducing license cost by finding and fixing misconfigurations and superfluous accounts
- How do CCB and CCX licenses really work?
- Understanding the DLAU tool and how to best utilize it
- Tips for common problem areas, like team mailboxes, functional/test users, etc
- Practical examples and best practices to implement right away
Observability Concepts EVERY Developer Should Know -- DeveloperWeek Europe.pdfPaige Cruz
Monitoring and observability aren’t traditionally found in software curriculums and many of us cobble this knowledge together from whatever vendor or ecosystem we were first introduced to and whatever is a part of your current company’s observability stack.
While the dev and ops silo continues to crumble….many organizations still relegate monitoring & observability as the purview of ops, infra and SRE teams. This is a mistake - achieving a highly observable system requires collaboration up and down the stack.
I, a former op, would like to extend an invitation to all application developers to join the observability party will share these foundational concepts to build on:
Unlock the Future of Search with MongoDB Atlas_ Vector Search Unleashed.pdfMalak Abu Hammad
Discover how MongoDB Atlas and vector search technology can revolutionize your application's search capabilities. This comprehensive presentation covers:
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For the full video of this presentation, please visit: https://www.edge-ai-vision.com/2024/06/building-and-scaling-ai-applications-with-the-nx-ai-manager-a-presentation-from-network-optix/
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2. Overview
● Basics of objects and classes
● Inheritance
● Polymorphism
● Abstract classes
● Interfaces
● Levels of access to class members
● The root Object class
● Generics
3. 1.1 Objects and Encapsulation
● Object-oriented language
Components that make up a Java application are
considered to be objects that interact with each
other.
4. 1.1.1 Objects
● Simulating a television on the computer.
Model the TV as an object.
● A TV is activated when it is powered on.
● The TV can be manipulated by changing its volume, the
channel it is tuned to, its brightness and contrast, etc.
● When it is powered off, the TV may retain its latest setting
for the next time it is switched on.
5. 1.1.1 Objects
● Programs may model non-physical objects as
well.
A graphical drawing package.
● Keeps track of all the figures the user draws on the
drawing pad, so it knows when, where, and how to
display these figures on the pad.
● Example: Rectangles.
An (x, y) location on the plane (i.e. The bottom-left corner of the
rectangle)
A width, w
A height, h.
6. 1.1.2 Lifetime, State and Messages
● Creation of a TV object.
TV objects will exist as long as the simulation runs.
The state of the TV may be changed by sending it
messages to switch channels, change volume, etc.
When a message is sent to the TV, it knows what to
do.
State of a TV object would comprise a set of
attributes, a variable with a certain value.
● Values of all the attributes together determine a current
state—if any one of these values is changed, the state is
changed.
7. 1.1.2 Lifetime, State and Messages
● The data and functions are therefore
encapsulated or enclosed within a single entity
that is the TV object.
The data are called fields, and the operations,
methods.
A Rectangle
● Fields
x and y coordinates, and its width and height values, w and h,
● Methods
drawing the Rectangle on the display, moving it, resizing it, and
so forth.
8. 1.1.3 Clients of an Object
● The sender of messages to an object is usually
referred to as the client of that object.
An object may have several clients that send
messages to it at different points in the lifetime of
the object.
9. 1.1.4 Separation of Interface from
Implementation
● The separation of interface from
implementation.
What an object is capable of doing is its behavior,
which is available to its clients via its methods, or
interface.
Exactly how this behavior is implemented by the
object is not known to its clients.
10. 1.2 Classes
● A class serves as a blueprint from which any
number of objects may be crated.
16. 1.2.1 State and Behavior
● The state TV is defined by its fields channel and
volume.
A TV can switchChannel, changeVolume, and
recallChannel.
switchChannel and changeVolume change the state of
the TV, recallChannel simply accesses the state.
MAX.VOLUME
Rectangle fields x, y, w, and h define the state of
any Rectangle.
Behavior defined by the methods moveTo, resize,
getX, getY, getWidth, and getHeight.
17. 1.2.2 Method Overloading
● Signature of a method name, and the number,
sequence, and type of its parameters.
The return type is not part of the signature.
The following have the same signature:
18. 1.2.2 Method Overloading
● In a class, no two methods can have the same
signature—if there are it does not compile the
program.
19. 1.2.2 Method Overloading
● The signatures of those methods are different,
since they have different types of arguments.
Contains method is overloaded.
20. 1.2.3 Object Creation, Constructors,
Garbage Collection
● The left-hand declares myTV to be a reference
of type TV.
● The right-hand side creates a TV object.
All objects must be created with new.
aTV does not refer to anything.
21. 1.2.3 Object Creation, Constructors,
Garbage Collection
● Creation occurs in two phases:
1. Allocating memory space for it, and initializes all its
fields to their default values.
2. The no-arg constructor (re)initializes its state as
required.
– A constructor:
● Has the same name as its class;
● Has no return value.
22. 1.2.3 Object Creation, Constructors,
Garbage Collection
● No-arg Constructor
A constructor that takes no parameters,.
The TV class has a no-arg constructor, which was
used to initialize a new TV object earlier.
The Rectangle class does not have a no-arg
constructor.
23. 1.2.3 Object Creation, Constructors,
Garbage Collection
● Parametered constructors
If TV objects need to be created with other initial
values for channel or volume, the parametered
constructor may be used instead:
24. 1.2.3 Object Creation, Constructors,
Garbage Collection
● Constructor code reuse
Calls the parametered constructor of the TV class.
Could have been:
Using this(...) reuses the code.
25. 1.2.3 Object Creation, Constructors,
Garbage Collection
● Explicit reference to current object.
This is a reference to the object on which the
constructor is invoke.
This is essential, the parameters channel and
volume would be indistinguishable from the fields of
the same names.
The parameters, hide the class fields of the same
name.
26. 1.2.3 Object Creation, Constructors,
Garbage Collection
● Compiler-supplied default constructor
Default constructor, no-arg construction with an
empty body.
Initializing the fields in the object to default initial
values based on their types.
Even when we create an object in class TV, which
does define constructors (i.e. There will not be a
default constructor supplied by the compiler).
27. 1.2.3 Object Creation, Constructors,
Garbage Collection
● Garbage collection
Memory space occupied by an object is reclaimed
by the garbage collector when the object is no
longer in use.
The first Rectangle object (10, 10) has no variable
referring to it.
● Not accessible any more, and is considered to be no
longer in use.
28. 1.2.3 Object Creation, Constructors,
Garbage Collection
● Garbage collector
Identifies that an object is not in use.
Determines the best time to reclaim the space used
by this object.
● Garbage collector is always silently running in the
background.
● Memory that is allocated when a new object is created, is
automatically garbage collected when it is no longer in
use.
29. 1.2.3 Object Creation, Constructors,
Garbage Collection
● C and C++
Two memory-related problems:
● The programmer “forgets” to free up space that had been
allocated earlier, but is no longer required (wasteful).
● The programmer tries to use memory that has been freed
up earlier, without realizing that it no longer belongs to
the program (dangerous).
31. 1.2.5 Static Fields and Methods
● Static fields
Switching the channel on tv1 has not affected the
channel setting on tv2 because their respective
channel fields are separate and different.
32. 1.2.5 Static Fields and Methods
● Static variables
Objects of a class may share a common resource.
This is a property of the class as a whole, not of
every object.
● MAX_VOLUME set a limit on the value of the volume
field.
● All TV objects will be able to share the MAX_VOLUME
resource.
● It may be accessed by using the class name instead of
an object name:
33. 1.2.5 Static Fields and Methods
Access via the class name is recommended
because it is then obvious that the field is static.
● Constants
final indicates that once a value is assigned to this
field, it may not subsequently change.
34. 1.2.5 Static Fields and Methods
● Static Methods
Utility methods applies to the class rather than any
particular object of that class.
● Invoked through the name of the class that contains it
and not through an object.
● All the methods the class Math are static, and so are its
fields.
36. 1.2.5 Static Fields and Methods
● Static methods can control the number of
instances of a class that may be created in an
application.
DrawingManager keeps track of all figures in a
drawing application, and does various other
managerial activities.
We only need one DrawingManager object in the
application.
37. 1.2.5 Static Fields and Methods
● The compiler will call an error because the
constructor is not visible outside the class.
Define a method that can deal out the one instance
of DrawingManager.
Must be static because it cannot be called on a
DrawingManager object.
39. 1.2.5 Static Fields and Methods
● All accesses are forced to be made through the
getInstance method, which correctly handles
the null case.
40. 1.2.5 Static Fields and Method
● Special static method main
main method is declared as static.
41. 1.2.6 Object References
● When an object is created using the new
construct, it is assigned space in memory.
Two distinct objects
One object that is reference by two names
42. 1.2.6 Object References
● Consider a method that takes some object as
parameter is called.
When objects are passed as a parameter to a
method, the parameter is a reference to the original
object and not a copy.
● Any changes to the object in the method will be reflected
in the object outside the method.
43. 1.3 Inheritance
● Notion of specialization that leads to reuse of
code is the basis of inheritance in object-
oriented programming.
44. 1.3.1 Superclass and Subclass
● B is a specialization of class A.
● A is inherited (and therefore reused) by class B.
● B is subclass.
● A is superclass.
45. 1.3.1 Superclass and Subclass
● Cars and motorcycles are both motorized
vehicles.
A car has four wheels instead of two, a steering
wheel instead of a steering bar, and so on.
Inheritance necessitates an is-A relationship
between the class that inherits and the class that is
inherited from.
Every Car is a MotorVehicle.
50. 1.3.1 Superclass and Subclass
● There are two methods in StereoTV, namely
checkSetBalance and setLeftRight, that simply
serve as helpers to the other methods of the
class (they are not declared public).
51. 1.3.2 Inherited and Specialized
Fields
When a class B is subclassed from A, it inherits all
the inheritable fields of A.
B can treat the inherited fields of A as its own.
52. 1.3.3 Constructors
● A superclass constructor is not inherited by its
subclass.
First handle the part inherited from the superclass,
if applicable, and then handle the specialization
part.
54. 1.3.5 Inherited and Specialized
Methods
● Inheritable methods of a class A are inherited
by its subclass B.
switchChannel, changeVolume, and recallChannel
of class TV are all inherited, and the code for each
reused, by StereoTV.
changeVolume; if it is inherited from TV, what is the
purpose of redoing it, and how can one prevent it
from conflicting with the inherited changeVolume?
55. 1.3.6 Method Overriding
● When the same functionality is provided and its
subclass, but the underlying implementations
are different, the subclass overrides the
superclass' implementation.
56. 1.3.6 Method Overriding
● Three kinds of methods a subclass may
implement:
A method that is special to the subclass.
A method that is inherited from the superclass.
A method that overrides an inherited method.
57. 1.4 THE Object CLASS
● When a class does not explicitly extend another
class, it implicitly extends the Object class.
● Every class in Java ultimately extends the
Object class.
58. 1.4.1 The equals Method
● equals method
Compares the object on which it is invoked with the
object referred to by the specified obj argument.
Returns true if these objects have equal value, and
false otherwise.
Assumes that an object is only equal to itself.
● equivalent to the == operator.
60. 1.4.1 The equals Method
● Default implementation of equals in the Object
class checks whether two objects are physically
the same.
● In the geometric sense, rectangles are equal if
their widths and heights are equal.
61. 1.4.1 The equals Method
● Overriding the equals method.
The if condition
● Check for null
● Check for correct instance.
Explicit cast to the type of the object.
The body evaluates to true or false.
Last statement (outside the if) returns false.
62. 1.4.2 The toString Method
● toString method
Used to print the value of an object to an output
stream.
Useful debugging tool
63. 1.4.2 The toString Method
● When a variable is sent as an argument to the
System.out.println() or System.out.print()
method, it automatically calls the toString
method.
64. 1.4.3 The clone Method
● clone Method
Makes a physical copy with the same state as the
source object.
Class must declare itself to implement an interface
called Cloneable, defined in java.lang.
66. 1.5 EXCEPTIONS
● We mistyped the number 10 as ‘‘1o’’.
● The program failed because an exception was
thrown at some point in the execution.
67. 1.5.1 Interpreting an Exception
Message
● The first line corresponds to the latest incident.
● The exception sequence is printed by the virtual
machine (VM), launched by the java command.
71. 1.5.2 Homegrown Error Handling
● ‘‘torpedo’’ approach
Detect the error as soon as it could have happened.
Print an error message
Exit the program right there.
● Any error will bring the program crashing down
right away without any hesitation.
73. 1.5.2 Homegrown Error Handling
● The burden of taking action on an error is on
the caller.
The caller has more contextual information, and is
able to handle problems more judiciously.
74. 1.5.2 Homegrown Error Handling
● Note that the answer 16! is smaller than for 15!
● 17! is a negative number.
● Those numbers are too large for an integer to
hold.
76. 1.5.2 Homegrown Error Handling
● Having a method’s return value mean either a
correct result or an error code is dangerous
because it confuses the issue and weakens the
link between the method and its caller.
● In the case of methods that do not return a
value, the approach to force error coding would
be more convoluted, and therefore more error-
prone.
77. 1.5.3 Throwing an Exception
● Java’s mechanism of using exceptions is a
uniform, well-engineered process that
separates normal execution from error
situations.
● An exception is an object.
At the point where an error is detected, an
exception object must be created and thrown
● This launches a separate control flow in the program that
is orchestrated by the virtual machine.
79. 1.5.3 Throwing an Exception
● As soon as an error is detected, an exception is
thrown.
● You need to choose an appropriate exception
object.
● The moment the exception is thrown, the
method from where it is thrown is exited
83. 1.5.4 Catching an Exception
● An exception that is thrown by a method can be
caught by the caller of the method.
● Must have a "try block"
Encapsulates a section to catch exceptions from.
It is followed by a catch block.
86. 1.5.4 Catching an Exception
● The entire try–catch combination is now inside
a while loop that will spin until a correct input is
entered and its factorial computed.
87. 1.5.4 Catching an Exception
● Try-Catch blocks can catch more than one
exception.
88. 1.5.4 Catching an Exception
● The order of the catches doesn't usually matter
if only one of the catches will apply at a time.
89. 1.5.4 Catching an Exception
● NumberFormatException is a subclass of
IllegalFormatException.
It will be matched against the first catch block, and
will never get to the second.
90. 1.5.5 Exception Class
● All exceptions are subclasses of the
java.lang.Exception class.
● Two basic constructors:
No-arg constructor.
A constructor with a single String argument that can
carry detailed messages.
Catching java.lang.Exceptions will catch any
exceptions thrown by a subclass.
92. 1.5.5 Exception Class
● printStackTrace() method.
Used by the virtual machine to print the entire
sequence of method calls up to the point where the
exception was thrown.
93. 1.6 INPUT AND OUTPUT
● The Java API has a wide variety of input-output
(IO) classes for many different requirements.
● java.util.Scanner class introduced in Java 1.5
can do much of the basic and most frequently
needed IO functions.
94. 1.6.1 Terminal-Driven IO
● Printing something to the terminal.
java.lang.System is a special class that contains a
(static) field called out.
It is of type java.io.PrintStream, and is called the
standard output stream.
95. 1.6.1 Terminal-Driven IO
● The simplest input method is to enter data via
the terminal.
● The System.in field is the standard input
stream, connected to the terminal by default.
● An input stream in Java can contain either text
data or binary data.
● We put an interpreter around System.in that can
parse the input as text.
java.util.Scanner
101. 1.6.2 File-Based IO
● Checked and unchecked exceptions.
All subclasses, immediate or otherwise, of
RuntimeException are called unchecked
exceptions, while all other exceptions are called
checked exceptions.
102. 1.6.2 File-Based IO
● When a method M gets a checked exception
back from a call to another method, then M
must either catch this checked exception or
throw it.
103. 1.6.2 File-Based IO
● Writing to a file.
Set up a File object.
Create a java.io.PrintWriter object with the file as
the target.
106. 1.6.4 Writing an Exception Class
● You can then define your own exception class.
107. 1.7.1 Java Packages
● The Java Application Programming Interface
(API).
A large collection of many hundreds of classes.
108. 1.7.1 Java Packages
● Refering to classes by their fully qualified
names.
The name of the class prefixed with the package to
which it belongs.
● e.g java.lang.String
● A Java class is automatically placed in an
anonymous, catch-all package, unless you
place it in a named package.
● java.lang is a special package.
No need to be fully qualified.
109. 1.7.1 Java Packages
● Using the import keyword, you can get around
fully qualifying class references.
● Using the ‘*’ is called wildcarding because it can
match anything that is a fit.
110. 1.7.2 Organizing Packages
● A package statement tells the compiler what
class goes into what package.
● The names we choose for our packages must
not conflict with the names of the java
packages.
111. 1.7.2 Organizing Packages
● Packages can be organized hierarchically.
● Create a folder for each package with the same
name as the package.
● Organize the Java source files for other classes
under their respective package folders.
112. 1.7.2 Organizing Packages
● When compiling a class that belongs to a
package by running javac from the command
line, you have to make sure that you are
positioned in the right folder.
113. 1.7.2 Organizing Packages
● Classes within the same package can refer to
each other without using fully qualified names.
Just like referring to java.lang classes.
● When an application gets large, you may need
to organize your subsystems into smaller
subsystems.
114. 1.7.3 Name Conflict Resolution
● You may have two classes with the same name
as long as their fully qualified names are
different.
● Example: Display
game.weapons.Display
game.actors.jedi.Display
game.scenarios.Display
● Confusion may arise if there is a conflict
between two classes with the same name.
115. 1.7.3 Name Conflict Resolution
● Example: structures.Stack
there is also a Stack class in the java.util package.
117. 1.4.1 Polymorphic Reference
● ref takes on a different “form” each time.
ref demonstrates polymorphic behavior.
● Polymorphism in the context of object-oriented
programming means that we can use a
reference of a superclass type to refer to an
object of that type, as well as any subclass
type, any number of levels down the class
inheritance hierarchy.
118. 1.4.1 Polymorphic Reference
● ClassB objects is-A ClassA object.
A reference of type ClassA should also be able to
refer to a ClassB object.
Every ClassC object is-A ClassA object; a reference
of type ClassA should also be able to refer to a
ClassC object.
120. 1.4.1 Polymorphic Reference
● We have no way of knowing until run time
whether the method will be invoked on a
StereoTV object.
changeVolume will be invoked on the appropriate
object at run time, depending on what tv refers to.
121. 1.4.2 Casting Up the Class
Hierarchy
● Java performs an implicit cast.
Casting up the class (inheritance) hierarchy.
123. 1.4.3 Casting Down the Class
Hierarchy
● Incorrect if tv were to refer to a TV object, since
TV does not define a setBalance method.
Correct if tv were indeed to refer to a StereoTV
object.
● The compiler is conservative about this, and flags the
statement as an error.
● Once “specialty” sets in, polymorphism is no longer
active.
124. 1.4.3 Casting Down the Class
Hierarchy
● If we know for sure that tv indeed refers to a
StereoTV object, cast down the class hierarchy.
If tv does refer to a TV object, the invocation of
setBalance will be rejected at run time.
125. 1.4.4 The Instanceof Operator
● instanceof operator determines the relationship
between a reference and the type of object to
which it refers at run time.
After the following:
● are all true
127. 1.5 Access Control
● Local variables of a method (including its
parameters) are visible only in the body of that
method.
Field and method of a class, as well as its
constructors, may be declared with one of the
following access control modifiers:
● Public
● Private
● Protected
If no access control modifier is specified, a package
level of accessibility is assumed.
128. 1.5.1 Public Access
● A public field or a method is accessible
anywhere the class is accessible.
The methods of class TV and class StereoTV are
declared public, and, since the respective classes
themselves are declared public, these methods are
accessible anywhere.
Except for the static fields, none of the fields of TV
or StereoTV are declared public.
● Since they have no access control modifiers, they are
accessible only within the same package.
129. 1.5.2 Package Access
● A field or method (or class) for which no access
control modifier is specified, is accessible, as
well as inheritable, by any class in its package.
If a class is not declared to belong to a specific
package, it is placed in a catch-all, unnamed
package, that is shared by all other classes for
which a package name is not specified.
There are two ways in which we can make classes
belong to the same package.
● Not name any package for either.
● Code a package name.
131. 1.5.3 Protected Access
● A protected field or method (or class) is
inherited by subclasses, is also accessible to
classes within the same package.
More access than package but less than public.
132. 1.5.4 Private Access
● A field or method declared private is only
accessible in the class itself.
133. 1.6 Abstract Classes
● A graphical geometry application, in which we
wanted to build objects for a variety of
geometric shapes such as line segments,
rectangles, circles, and so on.
Every such object, we wanted to be able to draw it,
scale it by a specified factor, translate it by a
specified amount and rotate it by a specified angle.
All geometric objects share these four common
operations, but exactly how it is implemented differs
from shape to shape.
136. 1.6 Abstract Classes
● Knowing that s1 (and s2) always refer to Shape
objects, it is always safe to invoke any of the
operations defined for Shape, and rely on the
fact that the actual object will take care of
drawing itself appropriately.
137. 1.6.1 Abstract Class Shape
● Shape itself is not real—it does not make sense
to create a Shape object.
Shape is an abstract class.
It declares certain operations that must be
supported by any subclass of Shape, but itself does
not implement any of them because it doesn't know
how to.
141. 1.6 Abstract Classes
● Declare with modifier abstract.
● If a class that is not declared abstract has an
abstract method, it would result in a compile-
time error.
● An abstract class may define fields that can be
inherited by its subclasses.
142. 1.6 Abstract Classes
● An abstract class may define one or more
constructors.
Objects, the constructor(s) is for the use of
subclasses—the constructor(s) may perform
initialization for the part that is inherited by
subclasses.
● An abstract class may define non-abstract
methods.
143. 1.6 Abstract Classes
● Each sub class of an abstract class may
override one or more of the abstract methods
inherited by it, with implementations that
effectively make those method non-abstract.
● A subclass of an abstract class need not
override all the inherited abstract method, with
implementations.
If the subclass does not provide an implementation
for at least one inherited abstract method, it
remains an abstract class.
144. 1.7 Interfaces
● Java provides a construct called interface that
may be used to define an explicit interface.
145. 1.7.1 The Java Interface Construct
● Interface is like an abstract class, in which none
of the methods are implemented and there are
no instance variables.
Any fields must be static.
146. 1.7.1 The Java Interface Construct
● Keyword class is replaced by the keyword
interface.
● All methods are implicitly public and abstract.
● Fields are implicitly public, static and final.
147. 1.7.2 Implementing an Interface
● A class may conform to an interface by
specifying that it implements that interface.
The class implements all the methods prescribed by
that interface, but is not restricted to only these
methods.
Any class that extends Rectangle will implicitly
implement ShapeInterface.
150. 1.7.4 The Need for Interfaces
● Terminal and Frame, model different types of
virtual windows, and a class called Manager
that is in charge of managing these windows.
Terminal class command-line interface to the
operating system.
151. 1.7.4 The Need for Interfaces
● Frame implements a work area with a menu7
bar, typically found in applications such as work
processors, drawing packages, etc.
152. 1.7.4 The Need for Interfaces
● Manager class manages graphic objects.
156. 1.7.4 The Need for Interfaces
● A class may implement more than one
interface.
157. 1.7.5 Extending Interfaces
● Like classes, interfaces may be extended.
Rdevice is an interface that specifies a computer
device that can read magnetic or optical media
such as a hard drive or a CD.
RWDevice is an interface specifies a computer
device that can not only read but also write to an
optical or magnetic device.
Since a read-write device is a read device and then
some, the specification of RWDevice extends that
of RDevice.
159. 1.8 The Object Class
● When a class is defined that does not explicitly
extend another class, it is implicitly assumed to
extend a class called Object, which is in the
package java.lang.
Every class in Java ultimately extends the Object
class.
There are two sets of methods in Object, general
utility methods, and those that support threads.
160. 1.9 Generics
● Many applications need to store collections of
objects.
It would be impractical to build one version for each
type of objects that needed to be stored using your
collection class.
Impossible to predict what types of objects would
possibly need to be sorted by the thousands of
applications that would potentially use your class.
One way to genericize your class would be to use
the catchall Object class.
162. 1.9 Generics
● Every reference in your class to any object in its
collection would use the Object type.
When an object is retrieved from the collection, the
application can convert it back to the particular type.
Work so long as the application does not need your
collection to apply any non Object type operations
when they are in the collection.
● i.e. Once it sends in a Shape to your collection, cannot
expect your collection to provide an operation that will
draw all shapes.
● Drawing operation is not defined in the Object class.
163. 1.9 Generics
● There is no way for the collection to tell whether
all objects in the collection are alike.
A generic class is said to be a template that can be
concretized to contain objects of any particular type
when the generic class itself is instantiated.
165. 1.9.1 Using java.util.ArrayList for
Collections
● The ArrayList is a generic array that can resize
itself automatically on demand.
When the sixth object is attempted to be added,
after exiting the for loop, the array list sees that it is
full to capacity.
The following actions are carried out:
166. 1.9.1 Using java.util.ArrayList for
Collections
● A new array of capacity 10 (double the previous
capacity of 5) is allocated.
● All items from the old array are copied to the
new.
● The new item to be added is appended to this
new array.
● The internal reference to the collection is
switched from the old array to the new array—
the old array is ready to be garbage collected.
167. 1.9.1 Using java.util.ArrayList for
Collections
● This process will be repeated if the array list is
full to capacity (all 10 locations are filled), and a
new item is asked to be added.
A new array of size 20.
ArrayList methods:
● add and remove items,
● get the current size,
● get an time at a given index,
● replace an item at a given index.
168. 1.9.2 The java.util.ArrayList
Interface
● Genericizing a class.
Define the class to accept a type parameter:
The type parameter is given a name (here the
name is E), which can then be referred everywhere
in the class where the type needs to be genericized.
This generic name is completely up to the class
implementor, although it is typically either E or T.
A constructor is defined:
169. 1.9.2 The java.util.ArrayList
Interface
● The object is created with the specific type
concretization of String, but the constructor
itself does not refer to the type parameter.
Methods int eh ArrayList class refer to the generic
type parameter in their header.
This method returns an object of generic type E.
170. 1.9.3 Implementing a Generic Class
● An array that stores its contents in sorted order.
All references to T in the SortedArray class are to
the one and the same T defined in the class header.
Items in our sorted array list are actually stored in
the ArrayList class.
172. 1.9.3 Implementing a Generic Class
● We can implement the constructors and the
indexOf methods by simply passing the buck to
the corresponding constructors and indexOf
method of the ArrayList class.
When a new item is added, it must be inserted in
the correct sorted position.
175. 1.9.4 Implementing a Generic
Interface
● When 7 is to be added to the sorted arry, it is
compared against array item, starting with the
first.
Each comparison needs to tell whether 7 is greater
than an array item or not.
178. 1.9.4 Implementing a Generic
Interface
● Define T to be not just any type, but a type that
provides a method to perform the less-than
comparison we need.
Use an interface that prescribes a less-than
comparison method, and a stipulate in our class
definition that T must be a type that implements this
interface.
179. 1.9.4 Implementing a Generic
Interface
● Example: Making integers conform to
MyComparable<T>.
Consider building a class that encapsulates an
integer value.
181. 1.9.4 Implementing a Generic
Interface
● The java language defines a generic interface
called Comparable<T> for this purpose.
Several of the Java language classes implement
this interface, including String and Integer.
184. 1.9.4 Implementing a Generic
Interface
● Every concrete instance of T must implement
the compareTo method, which will return a
value less than (or equal to) zero if the target
item (item) is less than (or equal to) the
parameter item (items.get(i)).
186. 1.9.5 Static Template Methods
● Sorter accepts either a sequence of integers, or
a sequence of strings, in any order, and prints
them out in sorted order.
188. 1.9.5 Static Template Methods
● Depending on whether the user wants to sort
integers or strings, the method sortIntegers or
sortStrings is called respectively;
192. 1.9.5 Static Template Methods
● A type name, T, is used without it having been
defined.
When we define the SortedArray class, we define
the type name T in the class header.
Sorter itself is not genericized as a whole, but we
need to genericize the single static method print.
In order to do this, we need to add a type definition
to the header.
193. 1.9.5 Static Template Methods
● We had defined the type parameter to
SortedArray as T extends Comparable<T>.
194. 1.9.5 Static Template Methods
● Static Template Method in Generic Class.
Suppose we want to define a static method in the
generic SortedArray<T> class that would take an
unsorted array, and return a sorted version of this
array in a SortedArray<T> object.
196. 1.9.5 Static Template Methods
● T defined here will not conflict with the T
defined in the header—they are separate,
independent T's.
197. Summary
● The two defining characteristics of object-
oriented programming are encapsulation and
inheritance.
● Encapsulation separaates interface from
implementation.
● Reusing an encapsulation means using an
object, time and again, as a component in other
objects.
198. Summary
● Inheritance makes it possible to build class
hierarchies that accurately model application
systems, and share code.
● A class is a blueprint for the creation of objects.
● An object once created is alive so long as there
is at least one reference to it.
● A message to an object leads to the invocation
of a method in that object.
199. Summary
● Two methods in a class with the same mane
but different signatures are said to be
overloaded.
● Overloaded methods provide similar
functionality in slightly different contexts.
● A method in a subclass that has the same
signature as a method is inherited from its
superclass is said to override the inherited
method.
200. Summary
● Polymorphism means a superclass reference
can refer to an object of any of its subclasses
along an inheritance hierarchy.
● The importance of polymorphism is that a
message that is sent via a superclass reference
can invoke the corresponding method in any of
its subclasses.
● Java defines four levels of access: private,
public, protected and package.
201. Summary
● Classes that are not related by inheritance can
be brought under the common umbrella of an
interface by a third class so that the latter may
apply one or more common operations to
objects of these classes.
● An interface may extend another interface.
● All classes in Java implicitly extend a root class
called Object.
202. Summary
● The Object class provides several methods that
have default implementations, equals.toString
and clone.
● A generic class is one that allows a choice of
client-defined types to concretize it.
● A generic class defines a parameter type in its
header.
203. Summary
● The parameter type defined in a generic class
header applies only to instance members; static
method, if generic, need to define a separate
local type parameter in the method header.
● An interface can be made generic, just like a
class.