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Java 11 - Optional Class
Java 11 - Optional Class
Java 11 introduced new method to Optional class as isEmpty() to check if value is present. isEmpty() returns false if value is present otherwise true.
It can be used as an alternative of isPresent() method which often needs to negate to check if value is not present.
Consider the following example −
ApiTester.java
import java.util.Optional; pubpc class APITester { pubpc static void main(String[] args) { String name = null; System.out.println(!Optional.ofNullable(name).isPresent()); System.out.println(Optional.ofNullable(name).isEmpty()); name = "Joe"; System.out.println(!Optional.ofNullable(name).isPresent()); System.out.println(Optional.ofNullable(name).isEmpty()); } }
Output
true true false falseAdvertisements