NPE when retrieving from HashMap even though containsKey() returns true in multithreaded environment We are trying to store unique object for a particular key. When getMyObject is called in multithreaded environment we are getting null ptr exception at the time of return statement object SampleClass { fun getMyObject(Id : String) : MyObject { if(!myMap.containsKey(Id)) { synchronized(SampleClass) { if(!myMap.containsKey(Id)) { myMap[Id] = MyObject() } } }...