A LinkedHashMap is the same as a HashMap, except that a LinkedHashMap maintains the insertion order, whereas a HashMap doesn’t. Internally, the LinkedHashMap uses a doubly-linked list to maintain the insertion order.
remove methodIn LinkedHashMap, we can use the remove method to remove the mapping of the specified key.
public V remove(Object key)
The key whose mapping is to be removed is passed as an argument.
If there is a mapping present for the specified key, then the mapping is removed and the removed value is returned.
If there is no mapping present for the specified key, then null is returned.
The below example shows how to use the remove method.
import java.util.LinkedHashMap;class RemoveExample {public static void main( String args[] ) {LinkedHashMap<Integer, String> map = new LinkedHashMap<>();map.put(1, "one");map.put(2, "two");System.out.println("The map is -" + map );String returnValue = map.remove(1);System.out.println("\nThe return value for remove method is -" + returnValue);System.out.println("The map is -" + map );returnValue = map.remove(3);System.out.println("\nThe return value for remove method is -" + returnValue);System.out.println("The map is -" + map );}}
In the code above:
In line 1, we imported the LinkedHashMap class.
In line 5, we created a LinkedHashMap object with the name map.
In lines 6 and 7, we used the put method to add two mappings ({1=one, 2=two}) to the map object.
In line 10, we used the remove method to remove the mapping for the key 1.
In line 14, we used the remove method to remove the mapping for the key 3. There is no such entry present, so null will be returned.