相关疑难解决方法(0)

我正在尝试使用Kotlin和Room Persistance Library编写一个简单的应用程序.我按照Android Persistance codelab中的教程进行操作.

这是我AppDatabase在Kotlin的课程:

@Database(entities = arrayOf(User::class), version = 1)
abstract class AppDatabase : RoomDatabase() {
    abstract fun userModel(): UserDao

    companion object {
        private var INSTANCE: AppDatabase? = null
        @JvmStatic fun getInMemoryDatabase(context: Context): AppDatabase {
            if (INSTANCE == null) {
                INSTANCE = Room.inMemoryDatabaseBuilder(context.applicationContext, AppDatabase::class.java).allowMainThreadQueries().build()
            }
            return INSTANCE!!
        }

        @JvmStatic fun destroyInstance() {
            INSTANCE = null
        }
    }
}

但是当我试图运行应用程序时,它会立即崩溃.这是崩溃日志:

Caused by: java.lang.RuntimeException: cannot find implementation for com.ttp.kotlin.kotlinsample.room.AppDatabase. AppDatabase_Impl does not exist
    at …

运行应用程序时出现以下错误

java.lang.RuntimeException: cannot find implementation for com.abc.db.abdDB. abcDB_Impl does not exist

我的build.gradle有以下配置:

implementation "androidx.lifecycle:lifecycle-extensions:2.0.0-alpha1"
annotationProcessor "androidx.lifecycle:lifecycle-compiler:2.0.0-alpha1"
implementation "androidx.room:room-runtime:2.0.0-alpha1"
annotationProcessor "androidx.room:room-compiler:2.0.0-alpha1"

我的数据库类:

fun getDatabase(context: Context): abcDB? {
        if (dbInstance == null) {
            synchronized(abcDB::class.java) {
                if (dbInstance == null) {
                    dbInstance = Room.databaseBuilder(context.applicationContext,
                            abcDB::class.java, "abc_db")
                            .fallbackToDestructiveMigration()
                            .addCallback(sRoomDatabaseCallback)
                            .build()
                }
            }
        }
        return dbInstance
    }

有没有人尝试使用androidX API？有人可以帮忙找到解决方案吗？