public ThreadFactoryBuilder taskFunction(
            Function<? super Runnable, ? extends Runnable> taskFunction) {
        this.taskFunction = requireNonNull(taskFunction, "taskFunction");
        return this;
    }
Sets task function for new threads.
Use this method to set additional work before or after the Runnable is run. For example:
<pre>{@code
ThreadFactories.builder("thread-prefix")
               .taskFunction( task -> {
                   return () -> {
                       // Add something to do before task is run
                       task.run();
                       // Add something to do after task is run
                   };
               })
               .build();
}</pre>
core/src/main/java/com/linecorp/armeria/common/util/ThreadFactoryBuilder.java