The java.util.TreeSet.comparator() method shares an important function of setting and returning the comparator that can be used to order the elements in a TreeSet. The method returns Null value if the set follows the natural ordering pattern of the elements.
comp_set = (TreeSet)tree_set.comparator()
Parameters: The method does not take any parameters.
Return Value: The method returns the comparator set used to order the elements of the set in a specific order. It returns a Null value if the set follows the default or natural ordering pattern.
Below are the programs illustrating the use of java.util.TreeSet.comparator() method:
Program 1: When using natural ordering of the elements:
Tree Set values are: [20, 24, 30, 35, 45, 50] Since the Comparator value is: null it follows natural ordering
Program 2: When using a specific comparator.
Set before using the comparator: [S, K, G, E, 4] The elements sorted in descendingorder: S K G E 4
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