Java HashMap getOrDefault()

Otherwise, the method returns the value corresponding to the specified key.

The syntax of the getOrDefault() method is:

hashmap.get(Object key, V defaultValue)

Here, hashmap is an object of the HashMap class.

getOrDefault() Parameters

The getDefault() method takes two parameters.

• key - key whose mapped value is to be returned
• defaultValue - value which is returned if the mapping for the specified key is not found

getOrDefault() Return Value

• returns the value to which the specified key is associated
• returns the specified defaultValue if the mapping for specified key is not found

Example: Java HashMap getOrDefault()

import java.util.HashMap;

class Main {
    public static void main(String[] args) {
        // create an HashMap
        HashMap<Integer, String> numbers = new HashMap<>();

        // insert entries to the HashMap
        numbers.put(1, "Java");
        numbers.put(2, "Python");
        numbers.put(3, "JavaScript");
        System.out.println("HashMap: " + numbers);

        // mapping for the key is present in HashMap
        String value1 = numbers.getOrDefault(1, "Not Found");
        System.out.println("Value for key 1:  " + value1);

        // mapping for the key is not present in HashMap
        String value2 = numbers.getOrDefault(4, "Not Found");
        System.out.println("Value for key 4: " + value2);
    }
}

Output

HashMap: {1=Java, 2=Python, 3=JavaScript}
Value for key 1:  Java
Value for key 4: Not Found

In the above example, we have created a hashmap named numbers. Notice the expression,

numbers.getOrDefault(1, "Not Found")

Here,

• 1 - key whose mapped value is to be returned
• Not Found - default value to be returned if the key is not present in the hashmap

Since the hashmap contains a mapping for key 1. Hence, the value Java is returned.

However, notice the expression,

numbers.getOrDefault(4, "Not Found")

Here,

• 4 - key whose mapped value is to be returned
• Not Found - default value

Since the hashmap does not contain any mapping for key 4. Hence, the default value Not Found is returned.

Note: We can use the HashMap containsKey() method to check if a particular key is present in the hashmap.