TreeMap entrySet() Method in Java Last Updated : 09 Jul, 2018 Comments Improve Suggest changes Like Article Like Report The java.util.TreeMap.entrySet() method in Java is used to create a set out of the same elements contained in the treemap. It basically returns a set view of the treemap or we can create a new set and store the map elements into them. Syntax: tree_map.entrySet() Parameters: The method does not take any parameter. Return Value: The method returns a set having same elements as the treemap. Below programs are used to illustrate the working of java.util.TreeMap.entrySet() Method: Program 1: Mapping String Values to Integer Keys. Java // Java code to illustrate the entrySet() method import java.util.*; public class Tree_Map_Demo { public static void main(String[] args) { // Creating an empty TreeMap TreeMap<Integer, String> tree_map = new TreeMap<Integer, String>(); // Mapping string values to int keys tree_map.put(10, "Geeks"); tree_map.put(15, "4"); tree_map.put(20, "Geeks"); tree_map.put(25, "Welcomes"); tree_map.put(30, "You"); // Displaying the TreeMap System.out.println("Initial Mappings are: " + tree_map); // Using entrySet() to get the set view System.out.println("The set is: " + tree_map.entrySet()); } } Output: Initial Mappings are: {10=Geeks, 15=4, 20=Geeks, 25=Welcomes, 30=You} The set is: [10=Geeks, 15=4, 20=Geeks, 25=Welcomes, 30=You] Program 2: Mapping Integer Values to String Keys. Java // Java code to illustrate the entrySet() method import java.util.*; public class Tree_Map_Demo { public static void main(String[] args) { // Creating an empty TreeMap TreeMap<String, Integer> tree_map = new TreeMap<String, Integer>(); // Mapping int values to string keys tree_map.put("Geeks", 10); tree_map.put("4", 15); tree_map.put("Geeks", 20); tree_map.put("Welcomes", 25); tree_map.put("You", 30); // Displaying the TreeMap System.out.println("Initial Mappings are: " + tree_map); // Using entrySet() to get the set view System.out.println("The set is: " + tree_map.entrySet()); } } Output: Initial Mappings are: {4=15, Geeks=20, Welcomes=25, You=30} The set is: [4=15, Geeks=20, Welcomes=25, You=30] Note: The same operation can be performed with any type of Mappings with variation and combination of different data types. Comment More infoAdvertise with us Next Article TreeMap firstEntry() and firstKey() Method in Java with Examples chinmoy lenka Follow Improve Article Tags : Misc Java Java-Collections java-TreeMap Practice Tags : JavaJava-CollectionsMisc Similar Reads TreeMap in Java TreeMap is a part of the Java Collection Framework. It implements the Map and NavigableMap interface and extends the AbstractMap class. It stores key-value pairs in a sorted order based on the natural ordering of keys or a custom Comparator. It uses a Red-Black Tree for efficient operations (add, re 11 min read Java TreeMap clear() Method The clear() method is a built-in method of the TreeMap class in Java of the java.util package. This method is used to remove all key-value mappings from the TreeMap. 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