Java Collection, HashMap Exercises: Remove all the mappings from a map
Java Collection, HashMap Exercises: Exercise-4 with Solution
Write a Java program to remove all the 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: {}
Java Code Editor:
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Previous: Copy all of the mappings from the specified map to another map.
Next: Check whether a map contains key-value mappings (empty) or not.
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Java: Tips of the Day
getEnumMap
Converts to enum to Map where key is the name and value is Enum itself.
public static <E extends Enum<E>> Map<String, E> getEnumMap(final Class<E> enumClass) { return Arrays.stream(enumClass.getEnumConstants()) .collect(Collectors.toMap(Enum::name, Function.identity())); }
Ref: https://bit.ly/3xXcFZt
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