In this example we shall show you how to check a value existence in a Hashtable. The Hashtable API provides methods for such operations. To check if a value exists in a Hashtable one should perform the following steps:
- Create a new Hashtable.
- Populate the hashtable with elements, using
put(K key, V value)API method of Hashtable. - Invoke
containsValue(Object value)API method of Hashtable, with a specific value as parameter. The method returns true if this hashtable maps one or more keys to this value and false otherwise,
as described in the code snippet below.
package com.javacodegeeks.snippets.core;
import java.util.Hashtable;
public class CheckValueHashtable {
public static void main(String[] args) {
// Create a Hashtable and populate it with elements
Hashtable hashtable = new Hashtable();
hashtable.put("key_1","value_1");
hashtable.put("key_2","value_2");
hashtable.put("key_3","value_3");
// boolean containsKey(Object key) returns true if the Hashtable contains the key, otherwise false.
boolean exists = hashtable.containsValue("value_2");
System.out.println("value_2 exists in Hashtable ? : " + exists);
}
}
Output:
value_2 exists in Hashtable ? : true
This was an example of how to check a value existence in a Hashtable in Java.
