Re: values for fields in failure/exception

mark jason <markjason72@gmail.com> writes:


  The purely object-oriented solution is as follows:

calculate( expression, success, failure );

  . ?calculate? does the calculation based on the object
  ?expression? and then calls the ?acceptResult? method of the
  object ?success? if the calculation was a success or the
  ?acceptFailure? method of the object ?failure? if the
  calculation failed.

  A partially object-oriented solution is as follows:

interface Result {};
class SuccessResult implements Result { /* result data here */ };
....
final Result result = calculate();
if( result instanceof SuccessResult )
{ final SuccessResult successResult =( SuccessResult)result;
  /* use data here */ }
else
{ /* error handling */ }

  Another solution uses exceptions:

try
{ final Result result = calculate();
  /* use data here */ }
catch( final CouldNotCalculateException couldNotCalculateException )
{ /* error handling */ }