What is Exception handling? Explain try, catch and finally with an example.

 Exception handling is a mechanism in Java that allows a programmer to handle runtime errors or exceptions in a controlled manner. When an exception occurs in a Java program, the normal flow of execution is interrupted, and the program terminates unless the exception is handled properly.

The try-catch-finally block is used to handle exceptions in Java. The try block contains the code that might generate an exception, and the catch block contains the code that handles the exception. The finally block contains code that is executed regardless of whether an exception is thrown or not.

Here is an example of how to use the try-catch-finally block to handle exceptions in Java:

public class ExceptionHandlingExample {
    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.");
        } finally {
            System.out.println("Finally block executed.");
        }
    }
}

In this example, we have a try block that performs a division operation, which may result in an ArithmeticException being thrown if the second operand is zero. The catch block catches this exception and prints an error message to the console. The finally block contains code that is always executed, regardless of whether an exception is thrown or not.

If we run this program, we will see the following output:

Error: Division by zero.
Finally block executed.

This output shows that the catch block is executed when an exception occurs, and the finally block is executed regardless of whether an exception is thrown or not.

In this example, the catch block handles the ArithmeticException that is thrown when the second operand is zero. If we had not caught this exception, the program would have terminated with an error message. The finally block is useful for performing cleanup operations, such as closing files or releasing resources, that should be executed regardless of whether an exception occurs or not.