groovy
implementation 'androidx.room:room-runtime:2.3.0'
annotationProcessor 'androidx.room:room-compiler:2.3.0'
@Entity(tableName = "users")
public class User {
@PrimaryKey
public int id;
@ColumnInfo(name = "name")
public String name;
}
@Dao
public interface UserDao {
@Query("SELECT * FROM users")
List<User> getAllUsers();
@Insert
void insertUser(User user);
}
@Database(entities = {User.class}, version = 1)
public abstract class AppDatabase extends RoomDatabase {
public abstract UserDao userDao();
private static AppDatabase instance;
public static synchronized AppDatabase getInstance(Context context) {
if (instance == null) {
instance = Room.databaseBuilder(context.getApplicationContext(),
AppDatabase.class, "app_database")
.fallbackToDestructiveMigration()
.build();
}
return instance;
}
}