Exception-handling.java

// Java Program to Demonstrate Exception is Thrown
// How the runTime System Searches Call-Stack
// to Find Appropriate Exception Handler

// Class
// ExceptionThrown
class Exception {

	// Method 1
	// It throws the Exception(ArithmeticException).
	// Appropriate Exception handler is not found
	// within this method.
	static int divideByZero(int a, int b)
	{

		// this statement will cause ArithmeticException
		// (/by zero)
		int i = a / b;

		return i;
	}

	// The runTime System searches the appropriate
	// Exception handler in method also but couldn't have
	// found. So looking forward on the call stack
	static int computeDivision(int a, int b)
	{

		int res = 0;

		// Try block to check for exceptions
		try {

			res = divideByZero(a, b);
		}

		// Catch block to handle NumberFormatException
		// exception Doesn't matches with
		// ArithmeticException
		catch (NumberFormatException ex) {
			// Display message when exception occurs
			System.out.println(
				"NumberFormatException is occurred");
		}
		return res;
	}

	// Method 2
	// Found appropriate Exception handler.
	// i.e. matching catch block.
	public static void main(String args[])
	{

		int a = 1;
		int b = 0;

		// Try block to check for exceptions
		try {
			int i = computeDivision(a, b);
		}

		// Catch block to handle ArithmeticException
		// exceptions
		catch (ArithmeticException ex) {

			// getMessage() will print description
			// of exception(here / by zero)
			System.out.println(ex.getMessage());
		}
	}
}