Map get() method in Java with Examples

Last Updated : 31 Dec, 2018

The get() method of Map interface in Java is used to retrieve or fetch the value mapped by a particular key mentioned in the parameter. It returns NULL when the map contains no such mapping for the key.

Syntax:

thisMap.get(Object key_element)

Parameter: The method takes one parameter key_element of object type and refers to the key whose associated value is supposed to be fetched.

Return Value: The method returns the value associated with the key_element in this Map collection.

Below programs illustrates the working of java.util.Map.get() method:

Program 1: Mapping String Values to Integer Keys.

// Java code to illustrate the get() method
import java.util.*;
  
public class Map_Demo {
    public static void main(String[] args)
    {
        // Creating an empty Map
        Map<Integer, String> map = new HashMap<Integer, String>();
  
        // Mapping string values to int keys
        map.put(10, "Geeks");
        map.put(15, "4");
        map.put(20, "Geeks");
        map.put(25, "Welcomes");
        map.put(30, "You");
  
        // Displaying the Map
        System.out.println("Initial Mappings are: " + map);
  
        // Getting the value of 25
        System.out.println("The Value is: " + map.get(25));
  
        // Getting the value of 10
        System.out.println("The Value is: " + map.get(10));
    }
}

Output:

Initial Mappings are: {20=Geeks, 25=Welcomes, 10=Geeks, 30=You, 15=4}
The Value is: Welcomes
The Value is: Geeks

Program 2: Mapping Integer Values to String Keys.

// Java code to illustrate the get() method
  
import java.util.*;
  
public class Map_Demo {
    public static void main(String[] args)
    {
        // Creating an empty Map
        Map<String, Integer> map = new HashMap<String, Integer>();
  
        // Mapping int values to string keys
        map.put("Geeks", 10);
        map.put("4", 15);
        map.put("Geeks", 20);
        map.put("Welcomes", 25);
        map.put("You", 30);
  
        // Displaying the Map
        System.out.println("Initial Mappings are: " + map);
  
        // Getting the value of "Geeks"
        System.out.println("The Value is: " + map.get("Geeks"));
  
        // Getting the value of "You"
        System.out.println("The Value is: " + map.get("You"));
    }
}

Output:

Initial Mappings are: {4=15, Geeks=20, You=30, Welcomes=25}
The Value is: 20
The Value is: 30

Note: The same operation can be performed with any type of Mappings with variation and combination of different data types.

Reference: https://docs.oracle.com/javase/7/docs/api/java/util/Map.html#get(java.lang.Object)

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