DEV Community: Bharadwaj

HTML - A Brief Introduction

Bharadwaj — Wed, 09 Jul 2025 13:25:04 +0000

HTML

HyperText Markup Language is a basic language to create and structure webpages. Like a skeleton of human body, HTML supports a website.

HTML focuses on defining the layout and presenting the content.

Let us understand each word in HTML.

What is HyperText?

This refers to the system that connect web pages to each other within the same website / across websites.

What is Markup?

Markup in this context refers to the use of tags to define the elements within a webpage. Tags (<, />) will determine how the text should be displayed. For example, header, paragraph, image, list, make a text bigger/smaller etc. can be defined through tags

Is HTML a programming language?

HTML is NOT a programming language. It is only a mark up language. There are no programming concepts like variable, loops and computational algorithms are involved in writing a HTML code.

Let us create a simple webpage

Type below code in a notepad and save as .html

<html>
<body>
<p1>

This is my first HTML page.

</p1>
</body>
</html>

Notice that the file has changed to a browser icon. Try opening the file and it opens in a browser with text "This is my first HTML page."

Java Architecture

Bharadwaj — Sat, 05 Jul 2025 16:46:53 +0000

Java Architecture:

Java architecture enables Java programs to be written once and run anywhere (WORA), providing platform independence, security, and efficient execution.

Java's Architecture is a collection of below components:

Java Development Kit (JDK)
JDK is the software development environment that offers tools and libraries required for developing Java applications. This contains the JRE and JVM required to write, compile and debug Java code. The Development tools under the JDK include a Java Compiler and Java Interpreter.

Java Runtime Environment (JRE)
JRE provides the libraries, Java Virtual Machine, and other components to run applications written in Java. It is essentially the JVM plus standard libraries and runtime files. JRE is included within the JDK but can also be downloaded separately for running Java programs.

Java Virtual Machine (JVM)
JVM is abstract virtual machine that executes Java bytecode. It converts bytecode into platform-specific machine code, enabling the same Java program to run on any device with a compatible JVM. It manages runtime memory areas and provides a secure execution environment.

Object Oriented Programming (OOP)

Bharadwaj — Mon, 30 Jun 2025 17:50:11 +0000

Let us look into Object Oriented Programming Concepts in a brief manner.

Programs in general contain data and code.

Process / Procedure Oriented model is a concept where the code is written in a way that it 'acts on the data'. For example, C programming language is written as series of procedures and functions.

OOP is a programming approach / style where the code is implemented 'around the data'. In other words, the data controls access to the code.

The data is referred to as 'Objects'.

What is an Object is this context?

Object is akin to a real world entity that has A) Properties and B) Actions

For example, consider Human being as object.

The object 'Human' has
Properties: Name, Gender, Age
Actions: Walk, Talk, Eat

Let us consider another example, 'Car' as an object.

The object 'Car' has
Properties: model, color, transmission type
Actions: Start, Stop, Accelerate

Properties of an object can also be referred as 'State' (or) 'Attributes'

Actions of an object can also be referred as 'Methods' (or) 'Functions'

What are the principles of OOP?

Let us understand the meaning of these words in simple English and then correlate to the programming approach.

Abstraction:

In our everyday lives, we manage and deal complexity through abstraction. For instance, we manage our home television features through a remote control device; however we may not bothered about the device internal design and ignore how it works. The remote control has specific functions and we understand how to use it through the buttons - TV Power ON / OFF, Volume Increase / Decrease, Channel Increase / Decrease, Mute etc.

In other words, the implementation details are hidden from the user.

This concept can be applied for writing software code where objects are defined as required for the business case. These objects have unique properties and behavior. The code is written in a way to tell the object what to do.

Encapsulation:

Think of a capsule that holds together medicine in a tube (or) container that doesn't expose the what's inside it to the outside world.

Encapsulation in OOP is a similar mechanism that binds data and code inside a wrapper not allowing other code to access. This is required to protect data from unauthorized access and modification.

The methods and variables defined within a class will be marked public or private to control the access. We'll review these topics in detail in upcoming weeks.

Inheritance:

Inheritance means an object acquiring the properties from another object. Imagine this concept like a child inherits the wealth from ancestors and still creates more wealth through his/her own talent. In programming, inheritance avoids rewriting same code for the related objects and helps in reusability.

Polymorphism:

Poly + Morph = multiple forms. Imagine a person known to you. He/She is likely to be parent at home, employee at an organization, social worker for community services etc. So, the person is same; yet depending on the territory their actions / behavior differs. Similar concept in OOP where the methods defined in one class shall exhibit different behavior based on parameters defined with it.

Java - Introduction

Bharadwaj — Sat, 28 Jun 2025 16:58:59 +0000

Dear friends, Let us get acquainted with Java.

What is Java?

Java is a high-level programming language.

Now, what is a high level programming language? A programming language designed in such a way that it is easier to read, understand, syntax similar to human language and hiding complex assembly level implementation details from the programmer is considered high level programming language. Example C, C++, C#, Java, Python etc.

Why Java is required?

Java was initially designed to serve hardware devices like microwave ovens, remote control, set top boxes that requires an platform independent software for embedded systems; yet with advent of internet Java's capabilities expanded to enterprise software systems. Java evolved as C and C++ programming languages could not solve certain complex problems. In other words, the way Java has been designed outweighed the advantages of C and C++ as a programming language.

Who designed Java and when was its first release?

Java was designed by James Gosling and his team at Sun Microsystems in 1991.

The first Java release was in 1995.

What the features of Java?

Simple and Easy to Learn
Object-Oriented Programming (OOP)
Platform Independence
Automatic Memory Management
Security
Rich Standard Library (API)
Multithreading
High Performance
Robustness
Architecture Neutral
Distributed Computing Support
Dynamic and Extensible

These features make Java an unique as well as robust high level programming language. In upcoming posts, each of the above topic will be discussed and reference links to be added accordingly.

What is the current version of Java?
The current version of Java as of June 2025 is Java 24 (Oracle JDK 24), which was officially released on March 18, 2025.

Arrays

Bharadwaj — Fri, 27 Jun 2025 04:06:24 +0000

Arrays:
Let us understand what is an 'Array' in general.
Collection / group / arrangement of objects is called an Array.

Rainbow is an array of colors.
An art exhibition has array of paintings.
Keyboard has an array of keys.

In Java (or in programming world), the concept of Array is similar. It is a collection of variables having same data type. Imagine this like a box with sequential tiny containers that has a name to it and can store something. (like a Pill Organizer box).

Why we need an Array?
This is a data structure concept. Array allows an easy way to group information that are similar and large is size. Otherwise declaring and storing large amount of details in variable would be time consuming. Complicates the program.

As mentioned earlier, the group of variables within an array should belong to one particular type. For example, each array that is defined shall store either integers (or) strings (or) boolean (or) java datatypes and custom objects. One cannot mix integers and strings in one array.

How to declare an Array?

Syntax: type var-name[];

Explanation:
'type' is the primitive data type followed by 'var-name' name for the variable

For example,

string week_days[];
int month_days[];

The above declaration does not create an Array as such; it only establishes an array variable 'week_days' (or) 'month_days'.

How to create an Array?

Syntax: array-var = new type [size]

Extending the same example given above,

week_days = new String [7];
month_days = new int [31];

Explanation:

array-var - 'week_days' and 'month_days' are the array variables.

new is the operator that allocate memory to create the array.

type is the type of the data being stored in the array

[size] defines the number of elements that can be stored in the array. In above example, 'week_days' array has size of 7 and 'month_days' array has size of 31.

The size of the array is fixed. After creating an array with a particular size, the value cannot be changed.

How to access elements in an Array?
Each element in an array is assigned with an index starting from 0. Index in this context mean a numerical position of the data so that one can refer and access what is inside that index.

For example, in 'week_days' array, the values will be stored in array like

week_days[0] = "Sunday";
week_days[1] = "Monday";
week_days[2] = "Tuesday";
week_days[3] = "Wednesday";
week_days[4] = "Thursday";
week_days[5] = "Friday";
week_days[6] = "Saturday";

The values 0 to 6 is the index. Say, if week_days[4] is called, 'Thursday' would be printed as that value assigned to the index at 4.

7 days a week; yet the index value stops at 6, because the array index starts at 0.

Let us see an example program that covers the above two steps
1) Declare Array variable with a data type
2) Create an array with specific size.

Example Program 01:

package arrays;

public class SimpleArray {

    public static void main(String[] args) {

        //Declaring the variable
        String week_days[];

        //Creating an array
        week_days = new String [7];


        //Assigning value to each index
        week_days[0] = "Sunday";
        week_days[1] = "Monday";
        week_days[2] = "Tuesday";
        week_days[3] = "Wednesday";
        week_days[4] = "Thursday";
        week_days[5] = "Friday";
        week_days[6] = "Saturday";

        System.out.println("First day of the work week is " + week_days[1]);
        }

}

Output of Example Program 01:
First day of the work week is Monday

Is there any other way to declare and create an Array? Yes

Declaration of Array Variable and creating an Array can be done in one statement.

Example:
//Declaring the variable
String week_days[];

//Creating an array
week_days = new String [7];

This can be rewritten as

String week_days [] = new String [7];

Arrays can also be initialized along declaration without the use of 'new' keyword. This is an alternate way to create and initialize arrays.

In same week_days example, the array can be created like

String week_days [] = {"Sunday","Monday","Tuesday","Wednesday","Thursday","Friday","Saturday"}

Note the usage of curly braces { } and 'new' keyword is not used.

Example Program 02:

package arrays;

public class ArrayCreation {

    public static void main(String[] args) {
        // Declare and initialize array
        String week_days [] = {"Sunday","Monday","Tuesday","Wednesday","Thursday","Friday","Saturday"};
        System.out.println("First day of the work week is " + week_days[1]);


    }

}

Output of Example Program 02:
First day of the work week is Monday

Both programs display the same output; yet the way arrays are declared and created differs.

More programs on Arrays, Array dimension to follow in upcoming posts.

New Beginning

Bharadwaj — Sat, 14 Jun 2025 05:50:35 +0000

Why am I learning Java in 2025?

Being in IT industry and Software Quality Assurance area for over 18 years, I felt not working in core programming or software development activities is a debt that is supposed to be fulfilled both from a knowledge and satisfaction level. This is my personal opinion and not generalizing. Also, over the last few years I start to learn something new in tech and lose momentum within few weeks. So, why Java and no other programming languages? No specific reason. I have to start somewhere, and Java aligns with my work requirements.

Why this blog and what will be covered?
This journal intends to capture the daily concepts learnt during the part of the Full Stack Development Course.