Chapter 6: Inheritance and Abstract Classes Chapter Topics 6.1 ...

CS151 Object-Oriented Design
Dr. Kim
{ try
{ int a = args.length;
System.out.println("a = " + a);
int b = 42 / a;
int [] c = { 5 };
c[42] = 99 ;
}
catch (ArithmeticException e)
{ System.out.println("Divided by 0: " + e);}
catch (ArrayIndexOutOfBoundsException e)
{ System.out.println("Array index oob: " + e);}
finally
{ System.out.println("This code is executed in anyway");}
System.out.println(“xx”);
}
}
• An exception handler recovers the problem, and has the program continues to run and
exit in a normal mode.
import java.util.Random;
public class HandleError
{ public static void main (String [] args)
{int a = 0, b = 0, c = 0;
Random r = new Random();
for (int i = 0 ; i < 100; i++)
{ try
{ b = r.nextInt();
c = r.nextInt();
a = 12345/ (b/c);
}
catch (ArithmeticException e)
{ System.out.println("Division by zero.");
a = 0 ; // set a to zero and move on
}
System.out.println("a: " + a);
}
}//main
}
• When you use multiple catch statements, ensure that catch blocks handling subclasses
come before those handling their superclasses. Note that a catch statement can handle the
specified class as well as it subclasses.
class SuperSubCatch
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