What does the Optional.orElseThrow() method introduced in Java 10 do?

Java MCQ: What does the Optional.orElseThrow() method introduced in Java 10 do?

Answer:

Explanation:

The Optional.orElseThrow() method, introduced in Java 10, returns the contained value if it is present; otherwise, it throws a NoSuchElementException. This method is similar to Optional.get(), but it provides a more descriptive and safe way to handle absent values, avoiding potential pitfalls of using Optional.get() directly.

Here’s an example of using Optional.orElseThrow():

import java.util.Optional;

public class OptionalOrElseThrowExample {
    public static void main(String[] args) {
        Optional<String> optionalName = Optional.of("John");

        String name = optionalName.orElseThrow();
        System.out.println(name);

        Optional<String> emptyOptional = Optional.empty();

        // This will throw NoSuchElementException because the Optional is empty
        emptyOptional.orElseThrow();
    }
}

In this example, optionalName.orElseThrow() returns “John” because the optional contains a value. However, emptyOptional.orElseThrow() will throw a NoSuchElementException because the optional is empty.

The Optional.orElseThrow() method is useful when you need to explicitly handle the absence of a value, making your code more robust and predictable by avoiding null-related issues.

Reference links:

https://www.rameshfadatare.com/learn-java-programming/
https://www.javaguides.net/p/java-tutorial-learn-java-programming.html