How to determine the type of component using Room for data storage?

A component using Room for data storage is usually part of the Data Layer in the application architecture. Most often, this is:

• Repository — a class that encapsulates data access logic and interacts with Room DAO.
• ViewModel — can use the repository to obtain data and provide it to the UI.

To determine the component type, look for:

• Room annotations (e.g., @Entity, @Dao) — these are data model classes and access interfaces.
• Logic for working with the database via DAO — this is the repository.

Example of identification:

// DAO — interface for data access
@Dao
interface UserDao {
    @Query("SELECT * FROM users")
    fun getAllUsers(): LiveData<List<User>>
}

// Repository — class using DAO
class UserRepository(private val userDao: UserDao) {
    val allUsers: LiveData<List<User>> = userDao.getAllUsers()
}

// ViewModel — provides data to UI
class UserViewModel(private val repository: UserRepository) : ViewModel() {
    val users: LiveData<List<User>> = repository.allUsers
}

Thus, a component with Room is usually DAO and repository, while ViewModel is a consumer of this data.