TreeSet is an implementation class of SortedSet. It was introduced from JDK1.2
The elements in the TreeSet are sorted by default in ascending order.We can add only the objects that are comparable type to TreeSet otherwise TreeSet throws ClassCastException.
The TreeSet doesn't support heterogeneous collection.Null cannot be inserted in TreeSet.
The Elements of the TreeSet compare themselves based on the comparable interface. Such comparison is known as mutual comparison.
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