GetDotByDotOrId will not check the validity of the id

[sinabakh]

Abstraction Layer's GetDotByDotOrId will not check if the given id number exist on graph or no.

[sinabakh]

@pmkary It seems to be a bigger problem than it appears. Cause we can't simply return False since it breaks the design pattern.

In other hands it seems GetDotByNumberId will return an empty Dot if no dot is found. What really happens when it return the empty Dot ? and is there an easy way to check if it returned an empty Dot ?

[pouyakary]

@sinabakh that's interesting...