Java: Remove all the mappings from a map

Last update on May 22 2025 13:15:30 (UTC/GMT +8 hours)

4. Remove All Mappings from Map

Write a Java program to remove all mappings from a map.

Sample Solution:-

Java Code:

import java.util.*;  
public class Example4 {  
   public static void main(String args[]) {
  HashMap <Integer,String> hash_map = new HashMap <Integer,String> ();
  hash_map.put(1, "Red");
  hash_map.put(2, "Green");
  hash_map.put(3, "Black");
  hash_map.put(4, "White");
  hash_map.put(5, "Blue");
  // print the map
  System.out.println("The Original linked map: " + hash_map);
  // Removing all the elements from the linked map
  hash_map.clear();
  System.out.println("The New map: " + hash_map);
 }
}

Sample Output:

The Original linked map: {1=Red, 2=Green, 3=Black, 4=White, 5=Blue}    
The New map: {}

For more Practice: Solve these Related Problems:

Write a Java program to clear a HashMap using clear() and then verify that its size is zero.
Write a Java program to remove all entries from a map that have a value matching a specified criterion.
Write a Java program to iterate over a map and remove entries one-by-one, printing each removed key.
Write a Java program to reinitialize a map by assigning a new instance and compare it with the original map.

Go to:

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Java Code Editor:

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