03-Exception-Handling-Introduction-in-Java.md

Exception Handling Introduction in Java

What is Exception Handling?

• Exception handling is a way to handle runtime errors so that the program does not stop unexpectedly.
• It helps in making the program more reliable and user-friendly.

Why do we need it?

• To avoid program crash
• To display meaningful messages
• To continue execution after an error

Basic Idea

• Code that may fail is placed inside try block.
• If failure occurs, the catch block handles it.
• The finally block runs regardless of success or failure.

Syntax

try { // risky code } catch (ExceptionType e) { // handle the error } finally { // cleanup code }

Example

public class ExceptionHandlingIntro { public static void main(String[] args) { try { int num1 = 10; int num2 = 0; int result = num1 / num2; System.out.println(result); } catch (ArithmeticException e) { System.out.println("Error: Division by zero is not allowed."); } finally { System.out.println("This block always executes."); } } }

Important Points

• A single try block can have multiple catch blocks.
• finally is optional but useful for cleanup.
• catch blocks must be ordered from specific to general.

Summary

• Exception handling allows a program to respond to errors in a controlled way.
• try, catch, and finally are the main tools used for this.