well, An exception is an error thrown by a class or method reporting an error in operation. For example, dividing by zero is undefined in mathematics, and a calculation can fail if this winds up being the case because of an error in user input. In this particular case an ArithmeticException is thrown, and unless the programmer looks for this exception and manually puts in code to handle it, the program will crash stating the exception thrown and a stack trace, which would be unhelpful to a casual user of a Java program. If the programmer handles the exception, he could deliver a useful error to the user and return the user to the beginning of the program so that they could continue to use it.
There are many different exceptions that can be thrown by a program, and the Java API contains quite a few. A lot are contained in the default package, java.lang; however, when you start using more functionality such as AWT, Swing, or java.io, the packages may also contain additional exceptions thrown by those libraries. As you start expanding the functionality, it might be a good idea to look at potential exceptions in the package and when they might be thrown in the course of your application.
Answered by
Romi
, an ibibo Master,
at
1:35 PM on July 06, 2008