T - The type of the value contained in this Optionalpublic interface Optional<T>
A container which may or may not contain a value. It is used for wrapping the return value of getter methods, where the return value might not be available.
If a value is present (available), theisPresent() method will return true and the value can be
retrieved using the get() method.| Modifier and Type | Method and Description |
|---|---|
T |
get()
Gets the value held by this
Optional, if a value is present. |
boolean |
isPresent()
Checks if a value is present in this
Optional. |
boolean isPresent()
Optional. Always use this method to determine, if the Optional
holds a value, before accessing it using the get() method.true if there is a value present, otherwise falseT get()
Optional, if a value is present. Always call the isPresent() method
to verify, that a value is available, before calling this method.T) held by this OptionalNoSuchElementException - if there is no value present in this OptionalCopyright © 2021. All rights reserved.