Java LinkedHashMap clear() Method Last Updated : 16 May, 2025 Comments Improve Suggest changes Like Article Like Report The clear() method in Java is a built-in method of the java.util.LinkedHashMap class. This method is used to remove all the key-value mappings from a LinkedHashMap. After invoking this method, the map becomes empty.This method is very helpful when we want to reuse an existing map object without creating a new one.Syntax of clear() Methodpublic void clear()Parameters: This method does not accept any parameters.Return Value: This method does not return any value i.e., its return type is void.Examples of Java LinkedHashMap clear() MethodExample 1: In this example, we are going to create a LinkedHashMap with integer keys and string values, then we will use the clear() method to remove all entries. Java // Java program to demonstrate // clear() on LinkedHashMap with Integer keys import java.util.LinkedHashMap; public class Geeks { public static void main(String[] args) { // Create a LinkedHashMap with Integer keys LinkedHashMap<Integer, String> m = new LinkedHashMap<>(); // Add entries to the map m.put(10, "Geeks"); m.put(15, "4"); m.put(20, "Geeks"); m.put(25, "Welcomes"); m.put(30, "You"); System.out.println("Initial Mappings are: " + m); // Clear all entries from the map m.clear(); System.out.println("After clear(): " + m); } } OutputInitial Mappings are: {10=Geeks, 15=4, 20=Geeks, 25=Welcomes, 30=You} After clear(): {} Explanation: Here, all entries were removed from the LinkedHashMap using clear() method.Example 2: In this example, we will map the Integer values to string keys using the clear() method. It also shows how duplicate keys behave. Java // Java program to demonstrate // clear() on LinkedHashMap with String keys import java.util.LinkedHashMap; public class Geeks { public static void main(String[] args) { // Create a LinkedHashMap with String keys LinkedHashMap<String, Integer> m = new LinkedHashMap<>(); // Add entries to the map m.put("Geeks", 10); m.put("4", 15); // Overwrites previous key m.put("Geeks", 20); m.put("Welcomes", 25); m.put("You", 30); System.out.println("Initial Mappings are: " + m); // Clear all entries from the map m.clear(); System.out.println("After clear(): " + m); } } OutputInitial Mappings are: {Geeks=20, 4=15, Welcomes=25, You=30} After clear(): {} Explanation: Here, the duplicate key "Geeks" was updated before clearing. And after calling the clear() method, all entries were removed and the map became an empty map.Important Points:The clear() method deletes all mappings from the LinkedHashMap.It does not delete the map object itself, it only deletes its contents.It is a void method and does not throw any exceptions.This method is very useful for resetting the map state without creating a new instance. Comment More infoAdvertise with us Next Article LinkedHashMap containsKey() Method in Java with Examples C chinmoy lenka Follow Improve Article Tags : Java Java-Collections Java - util package Java-LinkedHashMap Practice Tags : JavaJava-Collections Similar Reads Java LinkedHashMap LinkedHashMap in Java implements the Map interface of the Collections Framework. It stores key-value pairs while maintaining the insertion order of the entries. It maintains the order in which elements are added.Stores unique key-value pairs.Maintains insertion order.Allows one null key and multiple 7 min read Java LinkedHashMap clear() Method The clear() method in Java is a built-in method of the java.util.LinkedHashMap class. This method is used to remove all the key-value mappings from a LinkedHashMap. After invoking this method, the map becomes empty.This method is very helpful when we want to reuse an existing map object without crea 2 min read LinkedHashMap containsKey() Method in Java with Examples The java.util.LinkedHashMap.containsKey() method is used to check whether a particular key is being mapped into the LinkedHashMap or not. It takes the key element as a parameter and returns True if that element is mapped in the map.Syntax: Linked_Hash_Map.containsKey(key_element) Parameters: The met 2 min read LinkedHashMap get() Method in Java with Examples In Java, get() method of LinkedHashMap class is used to retrieve or fetch the value mapped by a particular key mentioned in the parameter. It returns NULL when the map contains no such mapping for the key. --> java.util Package --> LinkedHashMap Class --> get() Method Syntax: Linked_Hash_Ma 2 min read LinkedHashMap removeEldestEntry() Method in Java The java.util.LinkedHashMap.removeEldestEntry() method in Java is used keep a track of whether the map removes any eldest entry from the map. So each time a new element is added to the LinkedHashMap, the eldest entry is removed from the map. This method is generally invoked after the addition of the 3 min read LinkedHashMap and LinkedHashSet in Java The LinkedHashMap is just like HashMap with an additional feature of maintaining an order of elements inserted into it. HashMap provided the advantage of quick insertion, search, and deletion but it never maintained the track and order of insertion which the LinkedHashMap provides where the elements 3 min read Design LRU Cache Design a data structure for LRU Cache. It should support the following operations: get and put.get(key) - Returns the value of the given key if it exists in the cache; otherwise, returns -1.put(key, value) - Inserts or updates the key-value pair in the cache. If the cache reaches capacity, remove th 5 min read Hashing in Java In hashing there is a hash function that maps keys to some values. But these hashing function may lead to collision that is two or more keys are mapped to same value. Chain hashing avoids collision. The idea is to make each cell of hash table point to a linked list of records that have same hash fun 6 min read Differences between TreeMap, HashMap and LinkedHashMap in Java Prerequisite: HashMap and TreeMap in Java TreeMap, HashMap and LinkedHashMap: What's Similar? All offer a key->value map and a way to iterate through the keys. The most important distinction between these classes is the time guarantees and the ordering of the keys.All three classes HashMap, TreeM 5 min read Like