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.
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.
