Create Optional object and check its value - Java Lambda Stream

Java examples for Lambda Stream:Optional

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Description

Create Optional object and check its value

Demo Code



import java.util.Arrays;
import java.util.List;
import java.util.Optional;
import java.util.stream.Collectors;

public class OptionalMain1 {
  public static void main(String[] args) {
    System.out.println(Optional.ofNullable("Aman").isPresent());
    System.out.println(Optional.ofNullable(null).isPresent());
    List<String> strings = Arrays.asList("abc", "", "bc", "efg", "abcd", "", "jkl");
    List<String> filtered = strings.stream().filter(string -> !string.isEmpty()).collect(Collectors.toList());
    System.out.println(strings);/*from  w w  w . j a  v  a  2s  .  c  o m*/
    System.out.println(filtered);
  }
}

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