e.com/en/java/javase/11/docs/api/java.base/java/util/Set.html" title="class or interface in java.util" class="external-link">Set</a>&lt;<a href="https://docs.oracle.com/en/java/javase/11/docs/api/java.base/java/util/concurrent/Future.html" title="class or interface in java.util.concurrent" class="external-link">Future</a>&lt;<a href="https://docs.oracle.com/en/java/javase/11/docs/api/java.base/java/lang/Void.html" title="class or interface in java.lang" class="external-link">Void</a>&gt;&gt;</span>&nbsp;<sp