w3resource
Java Exercises

Java Collection, HashMap Exercises: Test if a map contains a mapping for the specified value

Java Collection, HashMap Exercises: Exercise-8 with Solution

Write a Java program to test if a map contains a mapping for the specified value.

Sample Solution:-

Java Code:

import java.util.*;  
public class Example8 {  
   public static void main(String args[]) {
  HashMap < Integer, String > hash_map = new HashMap < Integer, String > ();
  hash_map.put(1, "Red");
  hash_map.put(2, "Green");
  hash_map.put(3, "Black");
  hash_map.put(4, "White");
  hash_map.put(5, "Blue");
  // print the map
  System.out.println("The Original map: " + hash_map);
  System.out.println("1. Is value \'Green\' exists?");
  if (hash_map.containsValue("Green")) {
   //value exists
   System.out.println("Yes! ");
  } else {
   //value does not exists
   System.out.println("no!");
  }

  System.out.println("\n2. Is value \'orange\' exists?");
  if (hash_map.containsValue("orange")) {
   System.out.println("yes! - " );
  } else {
   System.out.println("No!");
  }
 }
}

Sample Output:

The Original map: {1=Red, 2=Green, 3=Black, 4=White, 5=Blue}           
1. Is value 'Green' exists?                                            
Yes!                                                                   
                                                                       
2. Is value 'orange' exists?                                           
No!       

Java Code Editor:

Contribute your code and comments through Disqus.

What is the difficulty level of this exercise?