core/src/main/java/io/methvin/watcher/DirectoryWatcher.java
public CompletableFuture<Void> watchAsync(Executor executor) {
    return CompletableFuture.supplyAsync(
        () -> {
          watch();
          return null;
        },
        executor);
  }
public CompletableFuture<Void> watchAsync(Executor executor) {
    return CompletableFuture.supplyAsync(
        () -> {
          watch();
          return null;
        },
        executor);
  }
Asynchronously watch the directories.

@param executor the executor to use to watch asynchronously