Java: Remove and get a key-value mapping associated with the greatest key in this map

Last update on May 23 2025 13:08:44 (UTC/GMT +8 hours)

20. Poll Last Entry from TreeMap

Write a Java program to remove and get a key-value mapping associated with the greatest key in this map.

Sample Solution:-

Java Code:

import java.util.*;
import java.util.Map.Entry;  
public class Example20 {  
          public static void main(String args[]) {

  // Create a tree map
  TreeMap < Integer, String > tree_map = new TreeMap < Integer, String > ();

  // Put elements to the map 
  tree_map.put(10, "Red");
  tree_map.put(20, "Green");
  tree_map.put(40, "Black");
  tree_map.put(50, "White");
  tree_map.put(60, "Pink");

  // polling first entry
  System.out.println("Value before poll: " + tree_map);
  System.out.println("Value returned: " + tree_map.pollLastEntry());
  System.out.println("Value after poll: " + tree_map);
 }
}

Sample Output:

Value before poll: {10=Red, 20=Green, 40=Black, 50=White, 60=Pink}     
Value returned: 60=Pink                                                
Value after poll: {10=Red, 20=Green, 40=Black, 50=White}

For more Practice: Solve these Related Problems:

Write a Java program to use pollLastEntry() on a TreeMap to remove and return the mapping with the greatest key, then display the modified map.
Write a Java program to implement a method that removes the last entry from a TreeMap and returns it along with the new highest key.
Write a Java program to repeatedly remove the last entry from a TreeMap until it is empty, printing each removed mapping.
Write a Java program to compare the greatest key before and after removal by using pollLastEntry() on a TreeMap.

Go to:

PREV : Poll First Entry from TreeMap.
NEXT : Get SubMap from Key to Exclusive Key.

Java Code Editor:

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