Java HashMap isEmpty() Method Last Updated : 16 Jan, 2025 Comments Improve Suggest changes Like Article Like Report The isEmpty() method in Java HashMap class is used to check whether the map contains any key-value mappings.Example 1: Checking isEmpty() after adding entries to the map Java // Mapping integer value to string keys import java.util.HashMap; public class Geeks { public static void main(String[] args) { // Creating an empty HashMap HashMap<String, Integer> hm = new HashMap<String, Integer>(); // Mapping int values to string keys hm.put("Java", 1); hm.put("Programming", 2); hm.put("Language", 3); // Displaying the HashMap System.out.println("The Mappings are: " + hm); // Checking for the emptiness of Map System.out.println("Is the map empty? " + hm.isEmpty()); } } OutputThe Mappings are: {Java=1, Language=3, Programming=2} Is the map empty? false Syntax of isEmpty() Methodpublic boolean isEmpty()Return Type: It returns true, if the map contains no key-value mapping. It returns false, if the map has one or more key-value mapping.Example 2: Check isEmpty() Before and After Adding Entries Java // Mapping String value to integer keys import java.util.HashMap; public class Geeks { public static void main(String[] args) { // Create an empty HashMap HashMap<Integer, String> map = new HashMap<>(); // Display the HashMap System.out.println("HashMap contents: " + map); // Check if the map is empty System.out.println("Is the map empty? " + map.isEmpty()); // Add key-value pairs map.put(1, "Java"); map.put(2, "Programming"); map.put(3, "Language"); // Display the updated HashMap System.out.println("Updated HashMap contents: " + map); // Check if the map is empty again System.out.println("Is the map empty? " + map.isEmpty()); } } OutputHashMap contents: {} Is the map empty? true Updated HashMap contents: {1=Java, 2=Programming, 3=Language} Is the map empty? false Example 3: Check isEmpty() on an Empty HashMap Java // Java program to demonstrate the working of isEmpty() import java.util.HashMap; class Geeks { public static void main(String[] args) { // Creating an empty HashMap HashMap<String, Integer> hm = new HashMap<>(); // Displaying the HashMap System.out.println("The Mappings are: " + hm); // Checking for the emptiness of Map System.out.println("Is the map empty? " + hm.isEmpty()); } } OutputThe Mappings are: {} Is the map empty? true Comment More infoAdvertise with us Next Article Java HashMap isEmpty() Method C chinmoy lenka Follow Improve Article Tags : Misc Java Java-Collections Java - util package Java-Functions Java-HashMap +2 More Practice Tags : JavaJava-CollectionsMisc Similar Reads Java HashSet isEmpty() Method The HashSet isEmpty() in Java is used to check if the HashSet is empty or not.Syntax of HashSet isEmpty() Methodboolean isEmpty()Return Type: This method returns "true" if the HashSet is empty, otherwise returns "false".Example: This example demonstrates how the isEmpty() method checks whether the g 1 min read Hashtable isEmpty() Method in Java The Hashtable.isEmpty() method is a built-in method of the java.util.Hashtable class. This method is used to check if the table is empty or not. The method returns true, if no key-value pair or mapping is present in the table, else it returns false.Syntax of Hashtable isEmpty() Methodhash_table.isEm 2 min read IdentityHashMap isEmpty() Method in Java The java.util.IdentityHashMap.isEmpty() method of IdentityHashMap class is used to check for the emptiness of the map. The method returns True if no key-value pair or mapping is present in the map else False. Syntax: Identity_Hash_Map.isEmpty()Parameters: The method does not take any parameters. Ret 2 min read ConcurrentHashMap isEmpty() Method in Java The isEmpty() method in Java's ConcurrentHashMap class is used to check whether the map is empty or not. It has the following signature: boolean isEmpty() The isEmpty() method works in a concurrent environment, which means that it can be called from multiple threads without causing any data race or 2 min read BitSet isEmpty() method in Java BitSet is a class defined in the java.util package. It creates an array of bits represented by boolean values. Prerequisite : Java BitSet | Set 1 Bitset.isEmpty() This method is used to check if there are any bits that are set to true, in the specified BitSet. This method returns true if this BitSet 2 min read Like