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)

Attention reader! Don’t stop learning now. Get hold of all the important Java Foundation and Collections concepts with the Fundamentals of Java and Java Collections Course at a student-friendly price and become industry ready.

My Personal Notes

Related Articles