TreeSet subSet() Method in Java Last Updated : 26 Nov, 2018 Comments Improve Suggest changes Like Article Like Report The java.util.TreeSet.subSet() is used to return a subset of the existing TreeSet within a range mentioned in the parameter. The method takes in an upper limit and a lower limit and returns all the elements mentioned in the range. The lower limit is included if the element is present within the set and the upper limit is excluded. Basically, it takes the subset greater than equal to the lower limit and strictly less than the upper element. Syntax: TreeSet tree_set.subSet(Object low_element, Object up_element) Parameter: low_element: This is of the type of the TreeSet and defines the lower limit or the starting element from which the subset is evaluated. This element is included in the subset. up_element: This is of the type of the TreeSet and defines the upper limit or the last element up to which the subset is evaluated. This element is excluded from the subset. Return Values: The method returns a subset of the TreeSet type mentioned within the given range of the parameters. Below programs illustrate the java.util.TreeSet.subSet() method: Program 1: Java // Java code to illustrate subSet() method import java.io.*; import java.util.Iterator; import java.util.TreeSet; public class Tree_Set_Demo { public static void main(String[] args) { // Creating an empty TreeSet TreeSet<Integer> tree_set = new TreeSet<Integer>(); // Adding the elements using add() tree_set.add(5); tree_set.add(1); tree_set.add(50); tree_set.add(10); tree_set.add(20); tree_set.add(6); tree_set.add(20); tree_set.add(18); tree_set.add(9); tree_set.add(30); // Creating the subset tree TreeSet<Integer> sub_set = new TreeSet<Integer>(); // Limiting the values till 5 sub_set = (TreeSet<Integer>)tree_set.subSet(6, 30); // Creating an Iterator Iterator iterate; iterate = sub_set.iterator(); // Displaying the tree set data System.out.println("The resultant values within the sub set: "); // Iterating through the subset while (iterate.hasNext()) { System.out.println(iterate.next() + " "); } } } Output: The resultant values within the sub set: 6 9 10 18 20 Program 2: Java // Java code to illustrate subSet() method when TreeSet // contains elements of String type import java.io.*; import java.util.Iterator; import java.util.TreeSet; public class Tree_Set_Demo { public static void main(String[] args) { // Creating an empty TreeSet TreeSet<String> tree_set = new TreeSet<String>(); // Adding the elements using add() tree_set.add("Welcome"); tree_set.add("To"); tree_set.add("Geek"); tree_set.add("4"); tree_set.add("Geeks"); tree_set.add("TreeSet"); // Creating the subset tree TreeSet<String> sub_set = new TreeSet<String>(); // Limiting the values till 5 sub_set = (TreeSet<String>)tree_set.subSet("4", "TreeSet"); // Creating an Iterator Iterator iterate; iterate = sub_set.iterator(); // Displaying the tree set data System.out.println("The resultant values within the sub set: "); // Iterating through the subset while (iterate.hasNext()) { System.out.println(iterate.next() + " "); } } } Output: The resultant values within the sub set: 4 Geek Geeks To Comment More infoAdvertise with us Next Article TreeSet subSet() Method in Java C chinmoy lenka Follow Improve Article Tags : Misc Java Java-Collections Java - util package Java-Functions java-treeset +2 More Practice Tags : JavaJava-CollectionsMisc Similar Reads TreeSet in Java TreeSet is one of the most important implementations of the SortedSet interface in Java that uses a Tree(red - black tree) for storage. The ordering of the elements is maintained by a set using their natural ordering whether or not an explicit comparator is provided. This must be consistent with equ 13 min read TreeSet add() Method in Java The Java.util.TreeSet.add() method in Java TreeSet is used to add a specific element into a TreeSet. The function adds the element only if the specified element is not already present in the set else the function return False if the element is not present in the TreeSet. Syntax: Tree_Set.add(Object 1 min read TreeSet addAll() Method in Java The java.util.TreeSet.addAll(Collection C) method is used to append all of the elements from the mentioned collection to the existing set. The elements are added randomly without following any specific order. Syntax: boolean addAll(Collection C) Parameters: The parameter C is a collection of any typ 2 min read TreeSet ceiling() method in Java with Examples The ceiling() method of java.util.TreeSet<E> class is used to return the least element in this set greater than or equal to the given element, or null if there is no such element. Syntax: public E ceiling(E e) Parameters: This method takes the value e as a parameter which is to be matched. Ret 2 min read TreeSet clear() Method in Java The Java.util.TreeSet.clear() method is used to remove all the elements from a TreeSet. Using the clear() method only clears all the element from the set and not deletes the set. In other words, we can say that the clear() method is used to only empty an existing TreeSet. Syntax: Tree_Set.clear() Pa 1 min read TreeSet clone() Method in Java The Java.util.TreeSet.clone() method is used to return a shallow copy of the mentioned tree set. It just creates a copy of the set. Syntax: Tree_Set.clone() Parameters: The method does not take any parameters. Return Value: The function just returns a copy of the TreeSet. Below program illustrates t 1 min read TreeSet contains() Method in Java With Examples TreeSet is one of the most important implementations of the SortedSet interface in Java that uses a Tree for storage. The ordering of the elements is maintained by a set using their natural ordering whether or not an explicit comparator is provided. This must be consistent with equals if it is to co 3 min read TreeSet descendingIterator() method in Java with Examples The descendingIterator() method of java.util.TreeSet<E> class is used to return an iterator over the elements in this set in descending order.Syntax: public Iterator descendingIterator()Return Value: This method returns an iterator over the elements in this set in descending order.Below are th 2 min read TreeSet descendingSet() method in Java with Examples The descendingSet() method of java.util.TreeSet<E> class is used to return a reverse order view of the elements contained in this set. The descending set is backed by this set, so changes to the set are reflected in the descending set, and vice-versa. If either set is modified while an iterati 2 min read TreeSet first() Method in Java The Java.util.TreeSet.first() method is used to return the first of the element of a TreeSet. The first element here is being referred to the lowest of the elements in the set. If the elements are of integer types then the smallest integer is returned. If the elements are of the string types then th 3 min read Like