How do I handle null values in ConcurrentHashMap?

How do I handle null values in ConcurrentHashMap?

In Java, ConcurrentHashMap does not allow null keys or values. You can use a placeholder object instead.

What if I need to store a value that can be null?

You might consider using Optional as a wrapper for your values, allowing you to represent the absence of a value.

Can you give me an example of using Optional with ConcurrentHashMap?

Sure! You can declare your map as ConcurrentHashMap<KeyType, Optional<ValueType>> and use Optional.empty() for null values.

Are there any performance implications of using Optional?

Using Optional can introduce some overhead, but it often improves code readability and safety.