This is an example of how to check a key existence in a LinkedHashMap. Checking if a key exists in a LinkedHashMap implies that you should:
- Create a new LinkedHashMap.
- Populate the linkedHashMap with elements, with
put(K key, V value)API method of LinkedHashMap. - Invoke
containsKey(Object key)API method of LinkedHashMap, with a specified key as parameter. The method returns true if this map contains a mapping for the specified key and false otherwise.
Let’s take a look at the code snippet that follows:
package com.javacodegeeks.snippets.core;
import java.util.LinkedHashMap;
public class CheckKeyLinkedHashMap {
public static void main(String[] args) {
// Create a LinkedHashMap and populate it with elements
LinkedHashMap linkedHashMap = new LinkedHashMap();
linkedHashMap.put("key_1","value_1");
linkedHashMap.put("key_2","value_2");
linkedHashMap.put("key_3","value_3");
// boolean containsKey(Object key) returns true if the LinkedHashMap contains the key, otherwise false.
boolean exists = linkedHashMap.containsKey("key_2");
System.out.println("key_2 exists in LinkedHashMap ? : " + exists);
}
}
Output:
key_2 exists in LinkedHashMap ? : true
This was an example of how to check a key existence in a LinkedHashMap in Java.
