Thread: java.lang.numberformatexception error

Hi, im new to java, and im having a problem.
i have written a program that allows the user to select a choice 1-5 from a menu. then the desired info is displayed. if any other numbers are entered and error message appears. but i would like this error message to appear also if the user enters a symbol or anything that is not a number 1-5. how do i do this?

whenever i enter a symbol i get a java.lang.numberformatexception error message.i know it has to do with the highlighted area.

below is part of my code:

do
		{
			do
			{
				//Runs Public Static void display_menu()
				display_menu();
				[COLOR="Red"]choice = Integer.valueOf(in.readLine()).intValue();[/COLOR]
 
				if ((choice < 1) || (choice > 5))
				{
					System.out.println("Error: invalid choice, please try again");
				}
			} while ((choice < 1) || (choice > 5));
			if (choice != 5)
			{
				switch (choice)
				{
					case 1: 
						//Runs Public Static void Village()
						village();
						break;
					case 2:
						//Creates Output Text
						System.out.println("----------------------------");
						System.out.println("---Milk Round Information---");
						System.out.println("----------------------------");
						System.out.println("Distributer's Name: Ben Siddall");
						System.out.println("Number of Pints Needed for Sale each day: " + milkman.pints_to_be_available_daily());
						System.out.println("Total Revenue for the Milk Round each week: "  + myFormat.format(milkman.milk_round_revenue())+" Pounds");
						break;
					case 3:
						//Creates Output ~Text
						System.out.println("-------------------------");
						System.out.println("---Farmer Information---");
						System.out.println("-------------------------");
						System.out.println("Farmer's Name: Caleb Green");
						System.out.println("Number of Pints needed each day: " + milkman.pints_to_be_available_daily());
						System.out.println("Number of Cows required to Produce milk: " + farmer.cows_required(milkman.pints_to_be_available_daily()));
						System.out.println("Total Revenue for the Farmer each week: " + myFormat.format(milkman.farmers_revenue()) +" Pounds");
						System.out.println("Predicted Annual Milk Production: " + farmer.expected_pints_year() + " Pints");
 
						break;
					case 4:
						//creates output text
						System.out.println("-------------------------");
						System.out.println("---Revenue Information---");
						System.out.println("-------------------------");
						System.out.println("Milk Round Revenue: " + myFormat.format(milkman.milk_round_revenue()) + " Pounds");
						System.out.println("Farmers Revenue: " + myFormat.format(milkman.farmers_revenue()) + " Pounds");
						System.out.println("Farmers percentage of the milk round revenue: " +  myFormat.format(milkman.farmers_percentage_revenue()) + " % ");
						System.out.println("Predicted Annual Revenue for the Milk Round: " + myFormat.format(milkman.annual_milk_revenue())  + " Pounds");
 
						break;
					default:
						break;
				}
			}
		} while (choice != 5);