Explain what a NullPointerException is and how it can arise.

Explain what a NullPointerException is and how it can arise.

Answer:  A NullPointerException is an exception that indicates that an operation was attempted on some object that is equal to null.  For instance, ChessPiece c; declares c to refer to a ChessPiece, but c has not yet been instantiated, so any message passed to c at this point will cause a NullPointerException.

Comments

Popular posts from this blog

Examine the collapse of Han. What factors explain how this occurred? How influential in Han Dynasty on Chinese History?

Summarize effective communication strategies in organizational hierarchies, and review the role and relevance of the organizational grapevine

Examine the age-structure diagrams of Sweden and Kenya below, and answer the following questions. Compare and contrast the two age structure diagrams in terms of two population dynamics - birth rate and death rate.