java 调用 Rooms inMemoryBuilder 方法时的 Room Persistence Library 运行时异常
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Room Persistence Library run time exception when calling Rooms inMemoryBuilder method
提问by dxpelou
When following the tutorial for setting up the Room persistence library I run in to this error when testing on an Android device.
按照设置 Room 持久性库的教程进行操作时，我在 Android 设备上进行测试时遇到了此错误。
java.lang.RuntimeException: cannot find implementation for PackageName.AppDatabase. AppDatabase_Impl does not exist
java.lang.RuntimeException：找不到PackageName.AppDatabase 的实现。AppDatabase_Impl 不存在
I know a similar question has been asked however the issues were due to kotlin gradle issues. Possible Duplicate
我知道有人问过类似的问题，但是这些问题是由于 kotlin gradle 问题造成的。可能重复
Test class:
测试类：
@RunWith(AndroidJUnit4.class)
public class LocalDatabaseTest {
private PhotoDao mPhotoDao;
private AppDatabase mDb;
@Before
public void createDb() {
Context context = InstrumentationRegistry.getTargetContext();
mDb = Room.inMemoryDatabaseBuilder(context.getApplicationContext(), AppDatabase.class).build();
mPhotoDao = mDb.photoDao();
}
@After
public void closeDb() throws IOException {
//mDb.close();
}
@Test
public void testPreConditions() {
assertNotNull(mDb);
}
Dao:
道：
@Dao
public interface PhotoDao {
@Delete()
public void delete(Photo... photos);
@Update
public void update(Photo ... photos);
@Insert
public void insert(Photo ... photos);
}
Database:
数据库：
@Database(entities = {Photo.class}, version = 1)
public abstract class AppDatabase extends RoomDatabase {
public abstract PhotoDao photoDao();
}
Stack Trace:
堆栈跟踪：
java.lang.RuntimeException: cannot find implementation for *PackageName*.AppDatabase. AppDatabase_Impl does not exist
at android.arch.persistence.room.Room.getGeneratedImplementation(Room.java:90)
at android.arch.persistence.room.RoomDatabase$Builder.build(RoomDatabase.java:340)
at pics.chooz.choozpics.LocalDatabaseTest.createDb(LocalDatabaseTest.java:40)
at android.support.test.internal.runner.TestExecutor.execute(TestExecutor.java:59)
at android.support.test.runner.AndroidJUnitRunner.onStart(AndroidJUnitRunner.java:262)
at android.app.Instrumentation$InstrumentationThread.run(Instrumentation.java:1853)
Gradle:
摇篮：
apply plugin: "com.android.application"
apply plugin: "android-apt"
android {
compileSdkVersion 25
buildToolsVersion "25.0.2"
defaultConfig {
applicationId "*Package Name*"
minSdkVersion 16
targetSdkVersion 25
versionCode 50
versionName "1.0.32"
multiDexEnabled true
testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
}
dexOptions {
javaMaxHeapSize "4g"
}
buildTypes {
release {
minifyEnabled false
proguardFiles getDefaultProguardFile("proguard-android.txt"), "proguard-rules.pro"
}
debug {
debuggable true
}
}
lintOptions {
abortOnError false
disable "ResourceType"
}
sourceCompatibility = 1.7
targetCompatibility = 1.7
compileOptions {
sourceCompatibility JavaVersion.VERSION_1_7
targetCompatibility JavaVersion.VERSION_1_7
}
packagingOptions {
exclude 'META-INF/ASL2.0'
exclude 'META-INF/LICENSE'
exclude 'META-INF/NOTICE'
}
}
dependencies {
androidTestCompile "com.android.support:support-annotations:$androidVersion"
androidTestCompile 'com.android.support.test:runner:0.5'
androidTestCompile 'com.android.support.test:rules:0.5'
compile "android.arch.persistence.room:runtime:1.0.0-alpha1"
annotationProcessor "android.arch.persistence.room:compiler:1.0.0-alpha1"
}
回答by dxpelou
I changed the 'annotationProcessor' keyword to 'kapt' in my gradle file. Like so:
我将 gradle 文件中的“annotationProcessor”关键字更改为“kapt”。像这样：
kapt "android.arch.persistence.room:compiler:1.0.0"
回答by solidak
Rule of thumb when using Kotlin:
使用 Kotlin 时的经验法则：
Replace your annotationProcessordependencies with kapt. Also, include apply plugin: 'kotlin-kapt'in your app's build.gradle.
更换你annotationProcessor有依赖关系kapt。此外，包括 apply plugin: 'kotlin-kapt'在您的应用程序的build.gradle.
回答by Simon Rolin
Have a look on this thread
看看这个线程
The solution is to replace :
解决方法是更换：
annotationProcessor "android.arch.persistence.room:compiler:VERSION"
with :
和 ：
kapt "android.arch.persistence.room:compiler:VERSION"
回答by galaxigirl
You must add the annotation processor dependency to the module where your AppDatabase is. I assumed that the app would take the depencency from my API library module, where my data model classes are, but apparently this is not the case.
您必须将注释处理器依赖项添加到 AppDatabase 所在的模块中。我假设该应用程序将从我的 API 库模块中获取依赖，我的数据模型类所在的位置，但显然情况并非如此。
Answer came from this google issue: https://issuetracker.google.com/issues/67520422And this SO answer: https://stackoverflow.com/a/43918701/1959110
答案来自这个谷歌问题：https: //issuetracker.google.com/issues/67520422而这个答案是：https: //stackoverflow.com/a/43918701/1959110
回答by Javatar
Had the same issue with
有同样的问题
- gradle 3.2.0-alpha09
- koltin 1.2.31
- gradle 3.2.0-alpha09
- 科尔廷 1.2.31
Due the removal of apply plugin: 'kotlin-kapt'and other buggy stuff.. I had to downgrade to kotlin 1.1.60 to make it work. Then use:
由于删除了apply plugin: 'kotlin-kapt'和其他有问题的东西..我不得不降级到 kotlin 1.1.60 才能让它工作。然后使用：
apply plugin: 'kotlin-kapt'
dependencies {
...
implementation 'android.arch.persistence.room:runtime:1.0.0'
kapt "android.arch.persistence.room:compiler:1.0.0"
}
an other option would be to write the DB entities/DAOs and DataBase in Java instead.
另一种选择是用 Java 编写 DB 实体/DAO 和数据库。
回答by Zeeshan Ali
In my case I have change scheme but forgot to change version number.
就我而言，我有更改方案但忘记更改版本号。
@Database(entities = {Task1.class, Task2.class}, version = 2)
@Database(entities = {Task1.class, Task2.class}, version = 2)
回答by Shaon
For kotlin
对于科特林
//Room
implementation "android.arch.persistence.room:runtime:1.0.0"
//Room annotation processor
kapt "android.arch.persistence.room:compiler:1.0.0"
apply plugin: 'kotlin-kapt'
回答by Musa Abdul Wadud
change the annotationProcessor from annotationProcessor 'android.arch.persistence.room:runtime:1.1.0' to annotationProcessor 'android.arch.persistence.room:compiler:1.1.0'
将 annotationProcessor 从 annotationProcessor 'android.arch.persistence.room:runtime:1.1.0' 更改为 annotationProcessor 'android.arch.persistence.room:compiler:1.1.0'
