Why conditional statements are needed in Java

Introduction

Conditional statements help a program make decisions. They let the program choose what to do based on different situations.

When you want the program to do something only if a certain condition is true.

When you want to check user input and respond differently based on what the user types.

When you want to repeat actions but stop when a condition is met.

When you want to handle errors or special cases in your program.

When you want to compare values and take different actions depending on the result.

Syntax

Java

if (condition) {
    // code to run if condition is true
} else {
    // code to run if condition is false
}

The condition is a statement that is either true or false.

The code inside the curly braces runs only if the condition matches.

Examples

This checks if someone is 18 or older and prints a message accordingly.

Java

if (age >= 18) {
    System.out.println("You can vote.");
} else {
    System.out.println("You are too young to vote.");
}

This uses multiple conditions to give different feedback based on the score.

Java

if (score > 90) {
    System.out.println("Excellent!");
} else if (score > 75) {
    System.out.println("Good job.");
} else {
    System.out.println("Keep trying.");
}

Sample Program

This program checks the temperature and prints if it is hot or not.

Java

public class Main {
    public static void main(String[] args) {
        int temperature = 30;
        if (temperature > 25) {
            System.out.println("It's hot outside.");
        } else {
            System.out.println("It's not hot outside.");
        }
    }
}

Important Notes

Always make sure your conditions are clear and simple to understand.

Use else if to check multiple conditions in order.

Summary

Conditional statements let programs choose what to do based on conditions.

They help handle different situations and user inputs.

Using if, else if, and else covers many decision needs.