Does Java declare "throws Exception" by default? -

consider following classes:

class x { public void met()    {    } } 

and

class y extends x {     public void met() throws nullpointerexception     {         throw new nullpointerexception();     } } 

from have read on other questions ( why can't overriding methods throw exceptions broader overridden method? , java method throwing exception )

i understand overriding method in subclass, has throw either same or subclass of exception thrown in overridden method.

do java methods throw @ least exception of type exception?

...in other words compiler adds throws exception

so class x this

class x {     public void met() throws exception {      } } 

i want clarify not mistaken fact default exception handler exception added.

related questions:

ioexception vs runtimeexception java

there 2 types of exceptions: checked exceptions (like parseexceptionwhen parsing text) , unchecked exceptions (like nullpointerexception).

checked exceptions must declared in method signature. unchecked exceptions may declared in method signature.

when overriding methods (from interface or super class) have specify exceptions, throwing in implementation. cannot declare throw checked exceptions in implementation not allowed in overridden method.

this allowed:

class x { void somemethod() } class y extends x { @override void somemethod() throws uncheckedexception } 

this not allowed:

class x { void somemethod() } class y extends x { @override void somemethod() throws checkedexception } 

this allowed:

class x { void somemethod() throws checkexception } class y extends x { @override void somemethod() }