Java Change HashMap Value

To change the value of an entry in a HashMap in Java, you can use the put method of the HashMap class. This method takes two arguments: the key of the entry and the new value for that entry.

For example, given a HashMap called map that maps strings to integers, you could change the value of the entry with key "foo" as follows:

map.put("foo", newValue);

This will update the value for the key "foo" in the HashMap to be newValue. If there is no entry with key "foo" in the HashMap, this method will add a new entry with key "foo" and value newValue.

Here's an example of changing the value of an entry in a HashMap:

import java.util.HashMap;

public class Main {
  public static void main(String[] args) {
    // Create a HashMap that maps strings to integers
    HashMap<String, Integer> map = new HashMap<>();

    // Add some entries to the map
    map.put("apple", 1);
    map.put("banana", 2);
    map.put("cherry", 3);

    // Print the map
    System.out.println(map);  // prints {apple=1, banana=2, cherry=3}

    // Change the value of the entry with key "banana"
    map.put("banana", 4);

    // Print the map again
    System.out.println(map);  // prints {apple=1, banana=4, cherry=3}
  }
}