Room database example

DATABASE

/**
 * Abstract Foodium database.
 * It provides DAO [DEtailsDap] by using method [getDEtailsDAO].
 */
@Database(
    entities = [UserDetails::class],
    version = 1,
    exportSchema = false
)
abstract class AuditDatabase : RoomDatabase() {

    /**
     * @return [userdeatsilsDao] Audit User Data Access Object.
     */
    abstract fun getDetailsDao(): UserDetailsDao

    companion object {
        const val DB_NAME = "audit_database"

        @Volatile
        private var INSTANCE: AuditDatabase? = null

        fun getInstance(context: Context): AuditDatabase {
            val tempInstance = INSTANCE
            if (tempInstance != null) {
                return tempInstance
            }

            synchronized(this) {
                val instance = Room.databaseBuilder(
                        context.applicationContext,
                        AuditDatabase::class.java,
                        DB_NAME
                    )
                    .fallbackToDestructiveMigration()
                    .build()

                INSTANCE = instance
                return instance
            }
        }

    }
}