Optional – dealing with uncertainty

Since it was created, null has been used and misused by developers innumerable times in innumerable programs. One of the common cases for null is, among others, to represent the absence of a value. That is not convenient at all; it could either represent the absence of a value or the abnormal execution of a piece of code.

Moreover, in order to access variables that can potentially be null, and mitigate undesired runtime exceptions like NullPointerException, developers tend to wrap variables with an if statement so those variables are accessed in safe mode. Although it works, this protection against nulls adds some boilerplate that has nothing to do with the functionality or the goal of the code:

if (name != null) {
  // do something with name
}

The preceding code overcomes the problems that the creator of null spotted in his famous quote during a conference in 2009:

"I call it my billion-dollar mistake. It was the invention of the null reference in 1965. At...