In this example we shall show you how to check a value existence in HashMap. To check if a value exists in a HashMap one should perform the following steps:
- Create a new HashMap.
- Populate the hashMap with elements, with the
put(K key, V value)API method of HashMap. - Invoke the
containsValue(Object key)API method of the HashMap with a specific value as parameter. The method will return true if the value exists in the HashMap, otherwise it will return false,
as described in the code snippet below.
01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 19 | package com.javacodegeeks.snippets.core;import java.util.HashMap; public class CheckValueHashMap { public static void main(String[] args) { // Create a HashMap and populate it with elements HashMap hashMap = new HashMap(); hashMap.put("key_1","value_1"); hashMap.put("key_2","value_2"); hashMap.put("key_3","value_3"); // boolean containsValue(Object key) returns true if the HashMap contains the value, otherwise false. boolean exists = hashMap.containsValue("value_2"); System.out.println("value_2 exists in HashMap ? : " + exists); }} |
Output:
value_2 exists in HashMap ? : true
This was an example of how to check a value existence in HashMap in Java.
