Android Development Android Data Storage 3

Question 1

Where does Android store internal app files that are accessible only to the app?

Accepted Answer

getFilesDir()

Answer

getFilesDir() returns the absolute path to the directory on the internal filesystem where app-private files are stored.

Question 2

What is the purpose of the ContentProvider in Android?

Accepted Answer

To share data between apps using a standard interface

Answer

ContentProvider allows an app to expose its data to other apps through a standardized URI-based interface.

Question 3

Which DataStore type stores typed objects using Protocol Buffers?

Accepted Answer

Proto DataStore

Answer

Proto DataStore stores data as typed Protocol Buffer objects, providing type safety and avoiding string keys used in Preferences DataStore.

Question 4

What happens to data in getCacheDir() when the device runs low on storage?

Accepted Answer

The system may delete cache files automatically

Answer

Files in the cache directory may be deleted by the system when storage is low, so apps should not rely on them for critical data.

Question 5

Which SQL clause is used in a Room @Query to filter results?

Accepted Answer

WHERE

Answer

The WHERE clause in Room SQL queries filters rows that meet a specified condition, just as in standard SQL.

Android Development Practice Test