Java Exception Handling

[Darr2cool78]

Ok so i made a program to take a user input from keyboard of a desired N**th Li**ne for Pas**cals Tr**ang**le and display it! Our teacher says we get extra marks for adding an exception handler for say a int value not being entered..any help would be greatly apreciated..

[orginal code removed]

 

[Garee]

You could try getting the user input via a seperate method and then putting that in a while loop to ensure input validity.

I am pretty confident this should work.

	public static void main(String[] args) 
	{
		int numbersList[] = new int[0];
		int lineNumber = 0;

		// Ask the user for the line number.
		while ( lineNumber < 1 )
		{
			lineNumber = getLineNumber();
		}

		displayNthLine(numbersList, lineNumber);
	}
	
	/*
	 * Will request input from the user and return an integer value of a line number.
	 */
	public static int getLineNumber()
	{
		Scanner inputScanner = new Scanner( System.in );
		int lineNumber = 0;
		
		try
		{
			System.out.println("Enter Required Line Number: ");
			lineNumber = inputScanner.nextInt();
			
			// Assuming line numbers start at one.
			if ( lineNumber < 1 )
			{
				System.out.println( "Invalid input: Line number must be greater than zero." );
			}
		}
		catch ( InputMismatchException e )
		{
			System.out.println( "Invalid input: Must be an integer." );
			System.out.println();
		}
		
		return lineNumber;
	}

 

[Darr2cool78]

Man that is fantastic very clever thinking, thanks so much (hope u dont mind i removed my original code incase class mates are snooping)