in src/main/java/com/spotify/sparkey/extra/PersistentThreadLocal.java [68:77]
private void setFallback(T value, Thread thread, long threadId) {
final T prevValue = fallback.put(threadId, value);
if (prevValue == null) {
if (!activeThreads.containsKey(threadId)) {
// New thread - register for death and clean up any dead threads
cleanupDeadThreads();
activeThreads.put(threadId, new RefWithThreadId(thread, threadId, deadThreads));
}
}
}