// How to decide between HashMap and TreeMap? // Java Set Interface Interview Questions ... // {5=Bradman 9996, 25=Dravid 12000, 45=Lara 10000, 55=Sachin 14000} // descendingMap method returns the ...

The Tech Edvocate ...

My best guess to what was causing this is that your TreeMap contained non-static inner class instances and that your outer class wasn't serializable or it contained a member that wasn't.