Sample Output

Here is a run of the program. The run encounters an ArrayIndexOutOfBoundsException . The catch block uses getMessage() to print the message in the exception, and then uses printStackTrace().

C:/chap81>java IndexPractice
Enter the data:8
Enter the array index:10
This is your problem: 10
Here is where it happened:

java.lang.ArrayIndexOutOfBoundsException: 10
        at IndexPractice.main(IndexPractice.java:18)
Good-by

Here is another run of the program, this time with an InputMismatchException. The InputMismatchException did not contain a message, so its getMessage() method returned a null string.

C:/chap81>java IndexPractice
Enter the data:rats
This is your problem: null
Here is where it happened:

java.util.InputMismatchException
        at java.util.Scanner.throwFor(Unknown Source)
        at java.util.Scanner.next(Unknown Source)
        at java.util.Scanner.nextInt(Unknown Source)
        at java.util.Scanner.nextInt(Unknown Source)
        at IndexPractice.main(IndexPractice.java:15)
Good-by

A more sensible program would use a loop to collect data from the user and place it in the array. Exceptions would cause the program to repeat the prompt. This would be much more user-friendly than halting. If a user had already entered 999 data items, it would not be friendly to crash if item 1000 is wrong!