Which one to throw??

[Sun LiWei]

class MyClass
{
class Inner
{
public void amethod() throws Exception{
throw new IOException();
}
};
class InnerA extends Inner
{
public void amethod() throws Error{
throw new ThreadDeath();
}
};
class InnerB extends Inner
{
public void amethod() throws RuntimeException{
throw new ThreadDeath();
}
};
}

I am confused .Class Inner throws Exception,but InnerA throws Error,InnerB throws RuntimeException.I remembered that the overridden method can't throw Exception that never throw,but according to this piece of code,it seems right??Why??

[George Pincharoen]

- Error is not an exception.
- The rule that overridden method can't throw Exception that never throw apply only checked exception,so InnerB can throw RuntimeException without problems.

[Barry Gaunt]

An overriding method may only throw a subset (possibly empty) of the set of checked exceptions declared to be thrown by the overridden method.
RuntimeException and its subclasses, and Error and its subclasses are not checked exceptions so the above rule is not applicable.
-Barry

[Anthony Villanueva]

Just to be nitpicky the overriding method can also throw a subclass of the exception thrown by the overriden class.

public class Test76
{
class Inner
{
void amethod() throws Exception {}
}
class InnerA
{
void amethod() throws SomeException {}
}
class SomeException extends Exception {}
}