Optional References - Java 8

Optional References

NulPointers are like stubbing your toes - you’ve been doing it since you could stand up, and no matter how smart you are today - chances are you still do. To help with this age-old problem Java 8 is introducing a new template called Optional<T>.  
Borrowing from Scala and Haskell, this template is meant to explicitly state when a reference passed to or returned by a function can be null. This is meant to reduce the guessing game of whether a reference can be null, through over-reliance on documentation which may be out-of-date, or reading code which may change over time.
Optional<User> tryFindUser(int userID) {
or -
void processUser(User user, Optional<Cart> shoppingCart) {
The Optional template has a set of functions that make sampling it more convenient, such asisPresent() to check if an non-null value is available, or  ifPresent() to which you can pass a Lambda function that will be executed if isPresent is true. The downside is that much like with Java 8’s new date-time APIs, it will take time and work till this pattern takes hold and is absorbed into the libraries we use and design everyday.
New Lambda syntax for printing an optional value -
value.ifPresent(System.out::print);

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