Category Archives: Week 1

Design Principles

The four fundamental ideas of Object-Oriented Programming are Encapsulation, Abstraction, Inheritance, and Polymorphism. OOP allows programmers to approach software development as if they were dealing with real-world objects. People in real life have the skills and expertise to do a variety of tasks. Objects in OOP feature fields for storing knowledge, state, and data, as well as the ability to perform a variety of operations. The basic terms we need to know before getting more into OOP are Object, Class, Method, and Instance.

Object – A class’s instance

Class – A model that describes an object’s functionality

Method – Changing the state of a class applies to all other instances of the class

Instance – Is similar to an object. The blueprint used to build the product is an instance of the class.

Let’s move on to the four fundamental ideas of Object-Oriented Programming:

Encapsulation

When objects are encapsulated inside a class, they each have a private state. Other objects can’t directly access this state, but they can only use a list of public functions to get at it. These functions allow the object to control its own state and no other class has access to it unless access is granted. As a developer, you must use the given ways to communicate with the object. The state of a class invoked by a method created a bond between the private state and public methods.

Abstraction

Abstraction is a continuation of encapsulation. To show just relevant information to an object, data is selected from a large pool. Abstraction is the technique used to get, remove, or select user data from a bigger pool. In the case of abstraction, you can use the same info gathered for a different app to power other programs with little or no coding changes.

Inheritance

Inheritance is the process through which one object gains access to all of the properties of another without actually changing anything about the original. For instance, a child gets personality qualities from both of their parents. Reusability is a significant benefit of inheritance. The existing class’s fields and methods can be reused. Inheritance might be single, multiple, multilevel, hierarchical and hybrid, in Java.

Polymorphism

Polymorphism makes it possible to utilize a class in the same way as its parent, which eliminates the possibility of confusion. As a result, each child sub-class retains its own functions and methods. Each of the child sub-classes should have unique variations.

In a conclusion, Object-Oriented Programming refers to programming languages that use objects. The goal is to implement real-world concepts, keep data and the functions that operate on it separate such that no other part of the code may access it, except for that function.

References:

https://info.keylimeinteractive.com/the-four-pillars-of-object-oriented-programming

https://www.geeksforgeeks.org/understanding-encapsulation-inheritance-polymorphism-abstraction-in-oops/

From the blog CS@worcester – Xhulja's Blogs by xmurati and used with permission of the author. All other rights reserved by the author.

REST Introduction

APIs play an integral role in the development of modern-day applications. Whether you are writing your API or integrating someone else’s, it is crucial to understand their functioning. There are many APIs, but the most common types are REST APIs that operate using HTTP and HTTPS. I chose to write about REST APIs because we will be working with them in this class. They are essential to understand for most development projects. The blog post “Best practices for REST API design” discusses the basics of a REST API, how they work, and development practices. The post also provides code examples using NodeJS with the ExpressJS library showing how the concept of a REST API is implemented.

According to the article, a REST API follows a set of standard design principles that allow users to quickly be able to work with the API. For example, a REST API should include method endpoints such as /GET /POST /PUT and /DELETE. These endpoints are used to send and receive data between the server and the client. The difference between the endpoints is the operations they perform. Sending a request to a GET endpoint will send the client data, a POST request will add data, and a DELETE request will remove data.

Although there are a set of rules a REST API must follow, there are many best practices left up to the developer that they should follow. For example, a REST API should send and receive data in JSON. JSON makes working with data simpler because it is in an easily transferable and structured format. The API should also run over HTTPS rather than HTTP to add an extra level of security between communication.

A REST API closely resembles the structure of a URL where each method is separated by a forward slash. To pass a parameter, a question mark is used followed by the variable name equal to a value. In order to be readable, the developer must name and structure the API paths wisely, based on the function an endpoint is responsible for. For example, a GET request to find a user by ID could look something like /user/findOne?id=120. In this example, the findOne method is prefaced by /user/, and we know the user id we are finding is 120. If the API replaced the word user for record, then the developer using the API would not know what type of data to receive in the request.

Finally, a REST API should be versioned, meaning the highest level path of the URL structure should be the API’s version number. Using the find user example, a versioned API would read /v1/user/findOne?id=120. If we made a change to our API, we could modify that in the v2 API without breaking the code written using the v1 API.

I will definitely use these tips while developing a REST API in the future. One of the most important guidelines I learned was to always send and receive data in JSON. In the past, I have made a REST endpoint return a single value such as a number. Without any context, the data from the API would be hard to understand. If the values were named in JSON then it would be easier to work with and manipulate.

Reference blog resource: stackoverflow.blog/2020/03/02/best-practices-for-rest-api-design

From the blog CS@Worcester – Jared's Development Blog by Jared Moore and used with permission of the author. All other rights reserved by the author.

Just A Refresher For OOP Concepts

Hello and welcome back to my blog! I had a really fun time during the first few weeks of the semester and I am looking forward to the rest of it. The first POGIL group activity we did caught me off guard since I did not remember what the terms abstraction, encapsulation, polymorphism, and inheritance meant. These concepts were taught in one of the earlier programming classes and I have done school projects and labs that involved these concepts in the past. But I don’t actually remember the terms or the clear cut definitions of them. Maybe part of the reason why I did not remember them is because we briefly went over those topics and we were also not forced to remember them since those classes were more about if you could write the code correctly. So that is why I decided to focus my blog around those four concepts. The in-class activity was a good refresher but I wanted to do research to fully have a firm understanding of them. Having a strong understanding of these concepts will help me later on in my computer science journey since these concepts are going to be seen over and over again in object orientated programming.

Let’s start with abstraction. Abstraction is basically hiding unnecessary details and leaving only the necessary and relevant details. Hiding unnecessary information is useful because, well, it is not needed to show that information to the user. An example in real life is your smart phone. All that’s important to the user is the screen and they do not need to know what processor or how much RAM the phone has.

Encapsulation is bundling data with the code that modifies the data and it can also prevent outside sources from accessing that data. In Java, encapsulation is used in classes where data can be declared as private and outside methods cannot access that data.

Polymorphism is the ability to take on many forms. In Java, that means you can perform one tank many ways. An example of that is calculating the area of a shape. You can use the same method area() to calculate the area of a triangle, octagon, or any other shape. There’s also overriding methods where the child class has the same method as the parent class.

Inheritance is gaining the properties of one class to another class. It’s like a parent-child relationship. In Java, a child class inherits all the methods and attributes from its parent class. The vehicle example is a really good one. Vehicle would be the parent class and car and truck would be the child classes. Both car and truck would share the same attributes from vehicle but also have their own attributes as well.