Exceptions - Beginning Java 2 SDK - page 317

System.out.println("Code at end of first try block in divide()");
return array[index + 2];
} catch(ArithmeticException e) {
System.out.println("Arithmetic exception caught in divide()");
throw new ZeroDivideException(index + 1); // Throw new exception
} catch(ArrayIndexOutOfBoundsException e) {
System.out.println(
"Index-out-of-bounds index exception caught in divide()");
}
System.out.println("Executing code after try block in divide()");
return array[index + 2];
}
The first change is to add the throws clause to the method definition. Without this we'll get an error
message from the compiler. The second change adds a statement to the catch block for
ArithmeticException exceptions that throws a new exception.
This new exception needs to be caught in the calling method main() :
public static void main(String[] args) {
int[] x = {10, 5, 0}; // Array of three integers
// This block only throws an exception if method divide() does
try {
System.out.println("First try block in main()entered");
System.out.println("result = " + divide(x,0)); // No error
x[1] = 0; // Will cause a divide by zero
System.out.println("result = " + divide(x,0)); // Arithmetic error
x[1] = 1; // Reset to prevent divide by zero
System.out.println("result = " + divide(x,1)); // Index error
} catch(ZeroDivideException e) {
int index = e.getIndex(); // Get the index for the error
if(index > 0) { // Verify it is valid and now fix the array
x[index] = 1; // ...set the divisor to 1...
x[index + 1] = x[index - 1]; // ...and set the result
System.out.println("Zero divisor corrected to " + x[index]);
}
} catch(ArithmeticException e) {
System.out.println("Arithmetic exception caught in main()");
} catch(ArrayIndexOutOfBoundsException e) {
System.out.println("Index-out-of-bounds exception caught in main()");
}
System.out.println("Outside first try block in main()");
}