In this Java article we want to learn about Exception Handling in Java, Exception handling is a fundamental concept in Java programming that allows you to handle errors and unexpected situations in your code. Java provides the best exception handling mechanism that allows you to catch, handle and recover from runtime errors that may occur in your program. in this article post we want to talk that what are exceptions, how they work, and how to handle them in your Java programs.
What are Exceptions in Java ?
An exception is an event that occurs during the execution of a program that disrupts normal flow of instructions. Exceptions are objects that are thrown by a method when an error occurs, and they are caught by another part of the program that can handle the exception. in Java exceptions are divided into two categories, checked exceptions and unchecked exceptions. Checked exceptions are exceptions that the compiler requires you to handle, while unchecked exceptions are exceptions that you are not required to handle.
Exception Handling in Java
To handle an exception in Java, you need to write code that catches the exception and provides a way to recover from the error. in Java you can use try catch block to catch exceptions. try block contains the code that may throw an exception, and catch block contains the code that handles the exception. if an exception is thrown in try block, program jumps to catch block and execut code in the catch block.
This is an example of how to use try catch block to catch and handle an exception in Java:
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try { // code that may throw an exception } catch (Exception e) { // code that handles the exception } |
In the above example try block contains the code that may throw an exception. if an exception is thrown the program jumps to the catch block and executes the code in the catch block. catch block catches exception and provides a way to handle the error.
Now let’s create practical example, suppose you have a method that divides two numbers and returns the result. if the second number is zero this method should throw an exception because dividing by zero is undefined.
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public class HelloWorld { public static void main(String[] args) { int result = 0; try { result = divide(10, 0); System.out.println("Result: " + result); } catch (ArithmeticException e) { System.out.println("Error: " + e.getMessage()); } } public static int divide(int a, int b) throws ArithmeticException { if (b == 0) { throw new ArithmeticException("Cannot divide by zero"); } return a / b; } } |
In the above example divide method checks if the second parameter is zero. if it is it throws an ArithmeticException with custom message.
Run the code and this will be the result
