Implicit and explicit exception difference

Question

Hi,

What's the difference between implicit exception and explicit exception?

If I declare catch block like: catch(Exception e). Is this implicitly declaring an exception, or explicitly?

Thanks in advance.

Answer 1

I don't believe there's any such term as "implicit exception" or "explicit exception". Are you thinking checked and unchecked exceptions perhaps?

I've just downloaded the language specification as a PDF, and the phrases "implicit exception" and "explicit exception" don't exist anywhere within it.

Could you say where you came across the terms?

Answer 2

I think implicitly instantiating an object is done without explicitly calling a constructor. I don't think you can do that in Java.

Example:

throw new Exception();

calls a constructor and then throws the newly created Exception object.

Answer 3

Neither. Catching is not declaring an exception. Declaring an exception happens on the method:

pubic void someMethod() throws Exception.

I'm not sure what you mean by implicit vs. explicit. You probably mean something like the difference between a runtime and checked exception, but you could also a mean a method which throws a Runtime exception, which is optional.

public void someMethod() throws NullPointerException

The throws in that case is purely optional, since it is a Runtime exception, nothing should happen differently.