Question

How to check if key exists in HashMap with Java

Answer 1

import java.util.HashMap;

public class MyClass {
    public static void main(String args[]) {
        HashMap<String, Integer> hashmap = new HashMap<>();

        hashmap.put("java", 1);
        hashmap.put("c", 2);
        hashmap.put("c++", 3);
        hashmap.put("python", 4);

        if (hashmap.containsKey("java")) {
            System.out.println("found");
        }
        if (!hashmap.containsKey("php")) {
            System.out.println("not found");
        }
    }
}



/*
run:

found
not found

*/

 

70+ SQL courses for beginners and professionals