Java HashSet.clear() is a method in the Java HashSet class that removes all elements from the set, leaving it empty. This method is used to reset or reuse a set without creating a new instance. Introduced in Java 1995 with Java 1.2, clear() is essential for memory management and maintaining efficient workflows in applications with dynamic collections.

https://docs.oracle.com/javase/8/docs/api/java/util/HashSet.html