JAVA CERTIFICATION QUESTION: Use the Optional class

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JAVA CERTIFICATION QUESTION: Use the Optional class

· java

The goal of this quiz is to test your knowledge of the Java Optional class.

Given the class:

import java.util.Optional;
public class OptionalArgs {
  public static void main(String[] args) {
    var v = Optional.ofNullable(args[0])
             .or(() -> Optional.ofNullable(args[1]))
             .flatMap(o -> Optional.empty())
             .stream().findFirst().orElse("default");
    System.out.print(v);
  }
}

What is the output if you run the compiled class as shown below? Choose one.

java OptionalArgs Java

A. A runtime exception
B. Blank output
C. Java
D. default

DETAIL

The answer is D.