Proposal: Add getRandom() default method to java.util.List

[Daniel Tavares]

Dear OpenJDK community,

I’d like to propose the addition of a getRandom() default method to the
java.util.List interface.

As a Java developer with over 15 years of experience, I’ve often found
myself needing to retrieve a random element from a list. While this can be
achieved using ThreadLocalRandom or by shuffling the list, these approaches
require boilerplate code and are not immediately intuitive—especially for
newcomers to the language.

*Motivation*

Retrieving a random element from a list is a common task in many domains:

   - Games and simulations
   - Educational tools
   - Random sampling in data processing
   - Lightweight testing scenarios

Adding a default method like getRandom() would improve readability and
reduce friction for developers, particularly those learning Java or working
on rapid prototyping.

*Proposed Method*

default T getRandom() {
    if (isEmpty()) return null;
    int index = ThreadLocalRandom.current().nextInt(size());
    return get(index);
}

Alternatively, the method could throw NoSuchElementException if the list is
empty, depending on what the community considers more idiomatic.

*Benefits*

   - *Improved developer experience*: Simplifies a common use case.
   - *Better readability*: Expresses intent directly.
   - *Minimal impact*: Can be added as a default method without breaking
   existing implementations.
   - *Alignment with modern Java*: Leverages default methods introduced in
   Java 8.


I understand that additions to core interfaces are considered carefully,
and I welcome feedback on whether this idea aligns with the design
philosophy of the Java Collections Framework.

Thank you for your time and consideration.

Best regards,

Daniel Perin Tavares
Curitiba, Brazil
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