exception

[sheri]

hi
try {
tryThis();
return;
} catch (IOException x1) {
System.out.println("exception 1");
return;
} catch (Exception x2) {
System.out.println("exception 2");
return;
} finally {
System.out.println("finally");
}
What will appear in the standard output if tryThis() throws a
NumberFormatException?
Select the one right answer.
a.Nothing
b."exception 1", followed by "finally"
c."exception 2", followed by "finally"
d."exception 1"
e."exception 2"
can anybody explain how the ans is c
since the NumberFormat Exception is not specified in any of the catch blocks.
thanx
sheri

[Carl Trusiak]

An Exception can be caught in a catch statement that is of the same type as the execption throw or is a super class of the excpetion thrown. The full tree for this is

java.lang.Object
  |
  +--java.lang.Throwable
        |
        +--java.lang.Exception
              |
              +--java.lang.RuntimeException
                    |
                    +--java.lang.IllegalArgumentException
                          |
                          +--java.lang.NumberFormatException

Since Exception is a super class of NumberFormatException it gets caught in the catch (Exception x2).
Hope this helps