Checking if a Map object contains a specific key

23 Sep 2023

// Create a HashMap
Map<String, Integer> map = new HashMap<>();

// Add some key-value pairs
map.put("one", 1);
map.put("two", 2);
map.put("three", 3);

// Check if the map contains a specific key
boolean containsKey = map.containsKey("two");
System.out.println("Contains key 'two': " + containsKey);

containsKey = map.containsKey("four");
System.out.println("Contains key 'four': " + containsKey);

Output:

Contains key 'two': true
Contains key 'four': false

In this example, we create a Map object called map and populate it with some key-value pairs. Then, we use the containsKey() method to check if the map contains the keys “two” and “four”. The results are printed to the console.

Remember to replace String and Integer with the actual types used in your Map object.