Re: Which exception to use here?

  What would be a good (runtime-)exception class from the
  standard library meaning ?For reasons I do not understand,
  a called submethod failed, and now I can't do my job.?

  For example, method ?m? calls ?div?, and ?div? might throw
  a checked exception named ?DivisionByZero?.

  The client of ?m? does not even know at all that ?m? does a
  division, so he should not get this exception, it would make
  no sense to him. Therefore, one would like to repack it into
  a (runttime-)exception that is intended to /make/ sense for
  m's client, but one also believes that this exception will
  never be thrown in the first place (and if it happens:
  indicate a programmer error, not a runtime failure in the
  sense of a harddisk device failure or so). So:

  What would be a good class to use instead of
  ?WhatToUseHereException? below?

public void m()
{ ...

  if( y != 0 )
  { try
    { q = div( x, y ); }
    catch( final DivisionByZero divisionByZero )
    { throw new WhatToUseHereException( divisionByZero ); }}

  ... }

  I believe, a runtime exception is more appropriate here than
  a checked exception, but do not know which specific runtime
  exception is best.