4.3.  Describe the unique characteristics of the Optional class


A java.util.Optional<T> object is either a wrapper for an Object of type T or a wrapper for no object. It is intended as a safer alternative than a reference of type T that refers to an Object or null.

Following is the declaration for java.util.Optional<T> class:

public final class Optional<T> extends Object {


Creating Optional objects

The first step before working with Optional is to learn how to create optional objects. There are several ways:

Unwrapping an Optional

The Optional class provides several instance methods to read the value contained by an Optional instance.

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