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Java Collection, TreeMap Exercises: Delete all elements from a given Tree Map

Java Collection, TreeMap Exercises: Exercise-6 with Solution

Write a Java program to delete all elements from a given Tree Map.

Sample Solution:-

Java Code:

import java.util.*;
import java.util.Map.Entry;  
public class Example6 {  
    public static void main(String args[]){  
    // Create a tree map
   TreeMap<String,String> tree_map1 = new TreeMap<String,String>();      
    // Put elements to the map 
  tree_map1.put("C1", "Red");
  tree_map1.put("C2", "Green");
  tree_map1.put("C3", "Black");
  tree_map1.put("C4", "White"); 
    
  System.out.println("Orginal TreeMap content: "+tree_map1);
  tree_map1.clear();
  System.out.println("The New map: "+tree_map1);
 }
}

Sample Output:

Orginal TreeMap content: {C1=Red, C2=Green, C3=Black, C4=White}        
The New map: {}

Java Code Editor:

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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