The pollLastEntry() method of NavigableMap interface in Java is used to remove and return a key-value mapping associated with the greatest key in this map, or null if the map is empty.
Syntax:
Map.Entry< K, V > pollLastEntry()
Where, K is the type of key maintained by this map and V is the type of values mapped to the keys.
Parameters: This function does not accepts any parameter.
Return Value: It returns a key-value mapping associated with the greatest key in this map, or null if the map is empty.
Below programs illustrate the pollLastEntry() method in Java:
Program 1: When the key is integer.
// Java code to demonstrate the working of // pollLastEntry() method import java.io.*;
import java.util.*;
public class GFG {
public static void main(String[] args)
{
// Declaring the NavigableMap of Integer and String
NavigableMap<Integer, String> nmmp = new TreeMap<>();
// assigning the values in the NavigableMap
// using put()
nmmp.put( 2 , "two" );
nmmp.put( 7 , "seven" );
nmmp.put( 3 , "three" );
System.out.println( "Removed key-value associated with" +
" greatest key : " + nmmp.pollLastEntry());
}
} |
Removed key-value associated with greatest key : 7=seven
Program 2: When the key is string.
// Java code to demonstrate the working of // pollLastEntry() method import java.io.*;
import java.util.*;
public class GFG {
public static void main(String[] args)
{
// Declaring the NavigableMap of Integer and String
NavigableMap<String, String> tmmp = new TreeMap<>();
// assigning the values in the NavigableMap
// using put()
tmmp.put( "one" , "two" );
tmmp.put( "six" , "seven" );
tmmp.put( "two" , "three" );
System.out.println( "Removed key-value associated with" +
" greatest the key : " + tmmp.pollLastEntry());
}
} |
Removed key-value associated with greatest the key : two=three
Reference: https://docs.oracle.com/javase/10/docs/api/java/util/NavigableMap.html#pollLastEntry()