You need to read some more on exception handling.

Well, the only advantage I can think of exception handling ( and
specific exception handling ), is the separation of errorhandling from
your logic.

Throwing specific exceptions indicates the user of your code, about the
error.

Like, if you are trying to add premium on an insurance policy, given
the policy number and premium amount. If insurance policy is not found,
you can throw an exception to the caller, telling that the policy
number is not found.

Of course, you need to figure out an optimum level, you cannot just go
around creating a new exception class for each and every error. You
might club some exceptions common to a module together.

Read this too, though it might be a bit intimidating if you are new to
Java.

http://www.mindview.net/Etc/Discussions/CheckedExceptions

Exceptions in Java are a good idea gone bad by overdoing it.Checked
exceptions are a nightmare. They are so hard to use that people swallow
exceptions (which is as bad as it gets) or they invent a new exception
for every layer that collects exceptions of the lower layer. Quite
often the real cause of the problems is 4-5 layers down. Java added the
getCause in 1.4 to allow for navigation through this space.For exampe,
if I call a database, do I want to get MySqlException, that points to a
some intermediate exceptions, that contain the final cause which
happens to be an IOException on a certain file. Only the last exception
is relevant.

Additionally, exceptions should be about exceptional cases.
Unfortunately, exceptions have been used to provide extra information
from the callee tot he caller. For example FileNotFoundException is not
an exceptional case, it is a normal event. Using exceptions for this is
expensive in runtime as well as annoying to read.

So exceptions are great, you should just not be forced to wrap your
exceptions in silly intermediates or be forced to specify all possible
exceptions that could be thrown. Most code should not try to handle the
exception, only top level code needs the exceptions to recover.