private static ThreadFactory build(ThreadFactoryBuilder builder) {
final String nameFormat = builder.nameFormat;
final Boolean daemon = builder.daemon;
final Integer priority = builder.priority;
final UncaughtExceptionHandler uncaughtExceptionHandler =
builder.uncaughtExceptionHandler;
final ThreadFactory backingThreadFactory =
(builder.backingThreadFactory != null)
? builder.backingThreadFactory
: Executors.defaultThreadFactory();