Source of DivideByZeroWithExceptionHandling.java


  1: // Fig. 13.2: DivideByZeroWithExceptionHandling.java
  2: // An exception-handling example that checks for divide-by-zero.
  3: import java.util.InputMismatchException;
  4: import java.util.Scanner;
  5: 
  6: public class DivideByZeroWithExceptionHandling
  7: {
  8:    // demonstrates throwing an exception when a divide-by-zero occurs
  9:    public static int quotient( int numerator, int denominator )
 10:       throws ArithmeticException
 11:    {
 12:       return numerator / denominator; // possible division by zero
 13:    } // end method quotient
 14: 
 15:    public static void main( String args[] )
 16:    {
 17:       Scanner scanner = new Scanner( System.in ); // scanner for input
 18:       boolean continueLoop = true; // determines if more input is needed
 19: 
 20:       do
 21:       {
 22:          try // read two numbers and calculate quotient
 23:          {
 24:             System.out.print( "Please enter an integer numerator: " );
 25:             int numerator = scanner.nextInt();
 26:             System.out.print( "Please enter an integer denominator: " );
 27:             int denominator = scanner.nextInt();
 28: 
 29:             int result = quotient( numerator, denominator );
 30:             System.out.printf( "\nResult: %d / %d = %d\n", numerator,
 31:                denominator, result );
 32:             continueLoop = false; // input successful; end looping
 33:          } // end try
 34:          catch ( InputMismatchException inputMismatchException )
 35:          {
 36:             System.err.printf( "\nException: %s\n",
 37:                inputMismatchException );
 38:             scanner.nextLine(); // discard input so user can try again
 39:             System.out.println(
 40:                "You must enter integers. Please try again.\n" );
 41:          } // end catch
 42:          catch ( ArithmeticException arithmeticException )
 43:          {
 44:             System.err.printf( "\nException: %s\n", arithmeticException );
 45:             System.out.println(
 46:                "Zero is an invalid denominator. Please try again.\n" );
 47:          } // end catch
 48:       } while ( continueLoop ); // end do...while
 49:    } // end main
 50: } // end class DivideByZeroWithExceptionHandling
 51: 
 52: 
 53: /**************************************************************************
 54:  * (C) Copyright 1992-2005 by Deitel & Associates, Inc. and               *
 55:  * Pearson Education, Inc. All Rights Reserved.                           *
 56:  *                                                                        *
 57:  * DISCLAIMER: The authors and publisher of this book have used their     *
 58:  * best efforts in preparing the book. These efforts include the          *
 59:  * development, research, and testing of the theories and programs        *
 60:  * to determine their effectiveness. The authors and publisher make       *
 61:  * no warranty of any kind, expressed or implied, with regard to these    *
 62:  * programs or to the documentation contained in these books. The authors *
 63:  * and publisher shall not be liable in any event for incidental or       *
 64:  * consequential damages in connection with, or arising out of, the       *
 65:  * furnishing, performance, or use of these programs.                     *
 66:  *************************************************************************/