Immutable Set in Java. As the name suggest these Set are immutable. If any attempt made to add, delete and update elements in the set we will have UnsupportedOperationException. Note that it is an immutable collection, not collection of immutable objects, so the objects inside it can be modified.Click to see full answer. Regarding this, is set mutable in Java?Set is a mathematical term which does not allow duplicates and is the case with Java Set. Set is agnostic about whether the object that you are inserting into it is mutable or immutable. It’s just like a collection which hold values.Furthermore, is set immutable? A set is an unordered collection of items. Every element is unique (no duplicates) and must be immutable (which cannot be changed). However, the set itself is mutable. We can add or remove items from it. Secondly, is list immutable in Java? Immutable List in Java. It means that the content of the List are fixed or constant after declaration, that is, they are read-only. If any attempt made to add, delete and update elements in the List, UnsupportedOperationException is thrown. An ImmutableList does not allow null element either.What is immutable in Java?In java, string objects are immutable. Immutable simply means unmodifiable or unchangeable. Once string object is created its data or state can’t be changed but a new string object is created. println(s);//will print Sachin because strings are immutable objects.