Forem: bagavath ravichandran

very good narration vasu

bagavath ravichandran — Thu, 08 May 2025 14:36:08 +0000

Vasudevan Tamilarasan

May 2 '25

Interface & Class

#java #classes #programming #beginners

Comments 2

3 min read

What are key words in java?

bagavath ravichandran — Thu, 03 Apr 2025 15:55:37 +0000

Keywords in Java are reserved words that have a predefined meaning in the language and cannot be used as variable names, method names, or identifiers.These keywords help define the syntax and structure of Java programs.

Here i'm presenting commonly used few keywords in java,

public (Access Modifier)

public is an access modifier that makes the method or class accessible from anywhere

If a method or class is public, it can be used by other classes, even if they are in different packages.

static (Modifier)

The static keyword means that a method or variable belongs to the class itself rather than to any specific instance of the class.

In the case of main, it means the method can be called without creating an object of the class.

void (Return Type)

void is a return type that specifies that a method does not return any value.

Since the main method is the entry point of the program, it doesn't return anything, so its return type is void.

class (Class Declaration)

class is a keyword used to define a class which is a blueprint for creating objects

main (Method Name)

main is the entry point of every Java application.

The JVM (Java Virtual Machine) calls the main method to start the execution of the program.

String[ ] args (Command-Line Arguments)

String[ ] args is an array of String values that store command-line arguments passed to the program when it's executed.

Example: If you run java MyClass hello world, args[0] = "hello" and args[1] = "world".

Static & Non-static methods in java .

bagavath ravichandran — Wed, 02 Apr 2025 16:36:03 +0000

Today i learned about what are the methods in java,

What is method in java?

 A method in Java is a set of instructions that can be called 
 for execution using the method name.

PicCourtesy-ScientechEasy

There are mainly two methods in java,
1.Pre-defined methods
2.user-defined methods

1.Predefined Methods:

These are methods that are already available and part of the Java class library. Examples include System.out.println() for printing to the console and Math.sqrt() for calculating square roots.

2.User-defined Methods:

These are methods that you, as the programmer create to perform specific tasks within your program. You define these methods within classes and use them to encapsulate functionality and improve code reusability.

In user-defined methods there are two types in it,

1.Static method
A static method is one that belongs to a class instead of an instance of a class and this method can be called without an instance or the object of the class.

2.Non-static method
non-static methods are methods that are associated with an instance of a class.

My mock interview experience

bagavath ravichandran — Mon, 31 Mar 2025 03:29:18 +0000

Today at my training institute the faculties arranged a mock interview for the students to get to know about the experience and the process of the interview.
At morning i arrived at the institute and made myself calm and chill by doing nothing and a little meditation, and i didn't rehearse the topic i learned and before the mock the training director arranged a group discussion session for 10 minutes and our group talked about the impcat of AI in our day to day life and i talked around a minute only and i learned new things from my fellow colleagues who talked in the session and training director gave a guidance speech about how to talk in a GD and the tips were very useful.
And then i went to get interviewed and the interviewer started to ask the questions and i answered it but i got nervous , after the session the interviewer gave some tips to overcome the weakness that's really helpfull and the session got over.
At the end of the day i gain new things and experiences.

PostgreSQL basics & clauses.

bagavath ravichandran — Wed, 26 Mar 2025 03:56:49 +0000

SQL:Structured query language
It is programming language for storing and processing information in a relational database.
PostgreSQL:PostgreSQL (often called Postgres) is a free, open-source database management system and one of the type of SQL that stores and manages data in tables. It's known for its reliability, flexibility, and performance and can handle large amounts of data.
CLAUSE
A clause in PostgreSQL is like a piece of a sentence in a SQL query. It helps tell the database what to do with the data. Think of it as giving step-by-step instructions.

Clauses are building blocks of SQL queries and help define operations such as filtering, sorting, grouping, and joining data.

-- FILTERING: Get employees older than 30
SELECT * FROM employees WHERE age > 30;

-- SORTING: Get employees sorted by salary (highest first)
SELECT * FROM employees ORDER BY salary DESC;

-- GROUPING: Count employees in each department
SELECT department, COUNT(*) FROM employees GROUP BY department;

-- JOINING: Get employees with their department names
SELECT employees.name, departments.name 
FROM employees 
JOIN departments ON employees.department_id = departments.id;

API & network topics

bagavath ravichandran — Mon, 17 Mar 2025 15:26:18 +0000

Today i learned about fetch API in javascript and other network protocols.

what is API?

     Application Programming Interface(API)  are a type of 
  software interface that enables applications to exchange 
  data,features, and functionality.

Types of APIs

Public APIs: Open APIs that are available to any business or developer.
Partner APIs: Only available to authorized businesses and developers.
Private APIs: Only accessible by one private enterprise.
Composite APIs: An aggregate of multiple APIs. (E.g.E-commerce checkout: Purchasing an item on Amazon involves multiple steps (adding to cart, checkout, payment) that are handled by a composite API in a single transaction.)

URI VS URL

uniform resource identifiers (URIs) and uniform resource
locators (URLs) aren't the same. A URI can be a name, a
location, or both, while a URL specifies just the location of
a resource.

FETCH (fetch is a concept or function) Fetch API is a specific JavaScript interface used to make HTTP requests to access data from APIs or other network resources.

The fetching process,

REST API

REST stands for Representational State Transfer and API stands for Application Program Interface. REST is a software architectural style that defines the set of rules to be used for creating web services.
It allows requesting systems to access and manipulate web
resources by using a uniform and predefined set of rules.

http headers

HTTP headers contain metadata in key-value pairs that are sent along with HTTP requests and responses. They can be used to define caching behavior, facilitate authentication, and manage session state.
https status code

HTTP status codes are three-digit codes that indicate the
outcome of an API request. They are included in the API's
response to the API client.

Javascript methods

bagavath ravichandran — Wed, 12 Mar 2025 12:29:36 +0000

Here are the methods i learned today,

1.appendchild()
This method adds a node to the end of the list of children of
a specified parent node

   E.g: 
       <script>             
        const document.createElement("h1")
        element.innertext="Hello"
        document.body.appendchild(element)
       </script>
  In here the appendchild will create a element with h1 tag 
  with the output as "Hello".

  In writing in script we can  directly create a element in the
  body from javascript.

2.append()

    This method inserts a set of Node objects or strings after 
    the last child of the document.

3.Difference b/w appendchild() and append()

 append() is used to add HTML content or an element to the end 
 of an existing element while appendChild() is used to add a 
 new node element as a child to an existing node.

My first website cloning project

bagavath ravichandran — Wed, 05 Mar 2025 12:40:04 +0000

the website is not correctly portrayed in this picture.

here's the code you can deploy

This project i had done using html & css only.

I've worked on this project for 2 days .As a beginner i felt frustrated on my work , some time i just froze on a particular code for almost 2 hours and i didn't gave up on my effort , I searhed on online for some properties and implemneted on this project and i got the output of this website.

The first thing how i able to finish my project is my
continuous practice . only with continuous
practice you can achieve and master anything.

CSS PROPERTIES

bagavath ravichandran — Thu, 27 Feb 2025 17:06:19 +0000

1.Flexbox:

 Flexbox is a layout method for arranging items in rows or 
 columns.
 The CSS Flexbox Layout should be used for one-dimensional 
 layout, with rows OR columns.

2.class selector

 The CSS .class selector selects elements with a specific class 
 attribute value.

 The **element.class** selector selects the specified elements 
 with the specified class attribute value.

3.Element selector.

 The element selector selects HTML elements based on the 
 element name.

p {
text-align: center;
color: red;
}

 Here, all <p> elements on the page will be center-aligned, 
 with a red text color:

4.Box-shadow property

 The CSS box-shadow property is used to apply one or more 
 shadows to an element.

 div {
     box-shadow: 10px 10px;
 }

5.Border-radius property.

 The border-radius property defines the radius of the element's 
 corners.it allows you to add rounded corners to elements.

 #example {
    border: 2px solid red;
    border-radius: 25px;
 }

TAGS IN HTML -1

bagavath ravichandran — Wed, 26 Feb 2025 15:43:47 +0000

These are the tags in HTMl

1.<!DOCTYPE html>

  The declaration is not an HTML tag. It is an "information" to 
  the browser about what document type to expect.

2.html

   This tag represents the root of an HTML document.The <html> 
   tag is the container for all other HTML elements (except for 
   the <!DOCTYPE> tag).

3.head

 The <head> element is a container for metadata (data about 
 data) and is placed between the <html> tag and the <body> tag.

4.body

 The <body> element contains all the contents of an HTML 
 document, such as headings, paragraphs, images, hyperlinks, 
 tables, lists, etc.

5.Heading tag.

 The <h1> to <h6> tags are used to define HTML headings.

6.Paragraph tag.

 The <p> tag defines a paragraph.Browsers automatically add a 
 single blank line before and after each <p> element.

7.Link tag.

 The <link> tag defines the relationship between the current 
 document and an external resource.
 E.g:
   <head>
   <link rel="stylesheet" href="styles.css">
   </head>

8.Footer tag.

 The <footer> tag defines a footer for a document or section.
 A <footer> element typically contains:

      - authorship information
      - copyright information
      - contact information
      - sitemap
      - back to top links
      - related documents

9.Input tag.

 The <input> tag specifies an input field where the user can 
 enter data.

 E.g:
    - <input type="button">
    - <input type="url">

10.Anchor tag .

 The <a> tag defines a hyperlink, which is used to link from 
 one page to another.

 The most important attribute of the <a> element is the href 
 attribute, which indicates the link's destination.
E.g:
 <a href="https://www.google.com">Visit google.com!</a>

FRONT END DEVELOPMENT-1

bagavath ravichandran — Tue, 25 Feb 2025 16:53:27 +0000

The front end development involves creating the visual and interactive aspects of a website or web application that users interact with directly . it focus on user interface(UI)&user experience(UX).

Front end relies on three technologies,

 1.HTML
 2.CSS
 3.JAVASCRIPT

1.HTML
HYPER TEXT MARKUP LANGUAGE(HTML)The backbone of any website, used to structure content on the wesite.

2.CSS
Cascading Style Sheets(CSS) Used to style and design the website, including layout, colors, fonts, and animations.

3.JAVASCRIPT
JavaScript is a programming language that makes websites interactive and dynamic.JavaScript runs in the browser on the user's device. It works alongside HTML (structure) and CSS (styling) to create a complete website.

APPS BUILD USING JAVA

bagavath ravichandran — Mon, 24 Feb 2025 08:20:01 +0000

The 10 apps that are build using java ,

 1.Uber
     A leading ride-sharing application that connects drivers 
  and passengers. Its backend services are developed using Java 
  to handle high volumes of data and transactions efficiently.

 2.Jenkins
        Jenkins, an open-source automation server, is primarily 
  written in Java and is widely used for continuous integration 
  and continuous delivery (CI/CD) in software development.

 3.Minecraft 
       A popular sandbox game that allows players to build and 
  explore virtual worlds. Its original version was developed 
  using Java. 

 4.Spotify
         A music streaming service that employs Java in its 
  backend to manage user data and streaming services 
  effectively.

 5.Netflix
        Netflix extensively utilizes Java in its technology 
  stack to build and maintain its streaming platform.

 6.Twitter
       Twitter's architecture has evolved significantly to meet 
  the demands of its growing user base. Initially built using 
  Ruby on Rails, Twitter transitioned to Java and Scala to 
  enhance performance and scalability. This shift allowed 
  Twitter to handle higher request rates and improve system 
  reliability

 7.Android Operating system
               The world's most widely used mobile operating 
   system, Android, is primarily built using Java. This enables 
   developers to create a vast array of mobile applications. 


 8.NASA WorldWind
               NASA WorldWind is an open-source 3D virtual 
  globe SDK developed by NASA's Learning Technologies project. 
  It enables developers to create cross-platform geospatial 
  applications in Java, providing access to a vast array of 
  satellite imagery, terrain data, and other geospatial        
  information.

 9.Citibank
          Citibank employs Java extensively across its 
  technology infrastructure to develop and maintain various 
  financial applications and services. The bank's technology 
  stack includes Java, among other languages and tools, to 
  support its global operations. 

 10.Walmart
       Walmart extensively utilizes Java in its technology 
  infrastructure to develop and maintain various applications 
  and services. The company employs Java for building scalable, 
  high-performance systems that support its global retail 
  operations.