When should you use a Map in Java?

Using a Map in Java is particularly appropriate when you need to store key-value pairs. A Map data structure allows you to associate unique keys with specific values, enabling efficient retrieval and manipulation of data based on these keys. This organization is beneficial when you require a quick lookup of values based on identifiable keys, as it provides an effective way to manage and access data.

Maps can store relationships and provide context, making them ideal for scenarios such as counting occurrences of items (where keys could be items and values could represent their counts), or creating associations like an employee ID linked to employee details. The ability to maintain these pairings is a significant advantage when working with data that needs to be referenced frequently and efficiently.

While other collections in Java, like Sets or Lists, serve their own purposes, they do not provide the same mechanism for key-value association. Thus, a Map is the go-to choice for scenarios specifically requiring this type of structure.