Sams Teach Yourself Java 2 in 21 Days, Second Edition

When and When Not to Use Exceptions

Because throwing, catching, and declaring exceptions are related concepts and can be very confusing, here's a quick summary of when to do what.

When to Use Exceptions

You can do one of three things if your method calls another method that has a throws clause:

• Deal with the exception by using try and catch statements

• Pass the exception up the calling chain by adding your own throws clause to your method definition

• Perform both of the preceding methods by catching the exception using catch and then explicitly rethrowing it using throw

In cases where a method throws more than one exception, you can handle each of those exceptions differently. For example, you might catch some of those exceptions while allowing others ...