Implement a no-reflection initialization of the generated RoomDatabase impl [316978491]

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Description

da...@google.com

created issue #1

Dec 19, 2023 03:36AM

In Android/JVM the RoomDatabase.Builder relies on reflection to instantiate the generated RoomDatabase class of an annotated @Database. For native there is no reflection and thus a no-reflection approach has to be implemented.

See go/room-reflection-replacement

Comments

el...@google.com <el...@google.com> Dec 21, 2023 08:38PM

Marked as fixed.

ap...@google.com <ap...@google.com> #2Dec 21, 2023 08:39PM

Project: platform/frameworks/support
Branch: androidx-master-dev

commit 3c819141d3be0a6194a6d02e5642942ac15d86af
Author: Daniel Santiago Rivera <danysantiago@google.com>
Date: Mon Feb 04 10:39:54 2019

Use JetBrains's Kotlin metadata library.

Use kotlinx-metadata-jvm to read Kotlin's Metadata annotation
information. This library has less of an API surface than kotlin-metdata
meaning KotlinClassMetadataUtils only exposes what Room needs. However
it does allows us to fix the JVM descriptors (JvmDescriptorUtils) that
are needed to match annotation processing elements to kotlin metadata
elements.

Bug: 123767877
Test: ./gradlew room:room-compiler:test \
room:integration-tests:room-testapp-kotlin:cC \
room:integration-tests:room-testapp:cC

Change-Id: Iddbe3968865b32168144294e55765a77320a40da

M buildSrc/src/main/kotlin/androidx/build/dependencies/Dependencies.kt
M room/compiler/build.gradle
D room/compiler/src/main/kotlin/androidx/room/ext/KotlinMetadataElement.kt
M room/compiler/src/main/kotlin/androidx/room/ext/element_ext.kt
A room/compiler/src/main/kotlin/androidx/room/kotlin/JvmDescriptorUtils.kt
A room/compiler/src/main/kotlin/androidx/room/kotlin/KotlinClassMetadataUtils.kt
A room/compiler/src/main/kotlin/androidx/room/kotlin/KotlinMetadataElement.kt
M room/compiler/src/main/kotlin/androidx/room/processor/MethodProcessorDelegate.kt
M room/compiler/src/main/kotlin/androidx/room/processor/PojoProcessor.kt
M room/compiler/src/main/kotlin/androidx/room/writer/DaoWriter.kt
A room/compiler/src/test/kotlin/androidx/room/kotlin/JvmDescriptorUtilsTest.kt
A room/compiler/src/test/kotlin/androidx/room/kotlin/KotlinMetadataElementTest.kt
M room/integration-tests/kotlintestapp/src/androidTest/java/androidx/room/integration/kotlintestapp/dao/BooksDao.kt
A room/integration-tests/kotlintestapp/src/androidTest/java/androidx/room/integration/kotlintestapp/vo/AnswerConverter.kt

https://android-review.googlesource.com/894734

https://goto.google.com/android-sha1/3c819141d3be0a6194a6d02e5642942ac15d86af

ap...@google.com <ap...@google.com> #3Dec 26, 2023 11:53AM

Project: platform/frameworks/support
Branch: androidx-main

commit 5fdb8c3223c1cdb1a0f0d27c0f32d42e8dc56106
Author: elifbilgin <elifbilgin@google.com>
Date: Thu Dec 21 08:16:28 2023

Adding a Native BuilderTest for room-runtime.

This CL introduces an initial BuilderTest in the nativeTest, which will have additional tests added once the DatabaseConfiguration has been fully moved to commonMain.

Bug: 316978491
Test: ./gradlew :room:integration-tests:room-testapp-kotlin:kspWithKspGenKotlinDebugAndroidTestKotlin
Change-Id: I6e2dabb33284595907fa8d904575437ebca416e5

M room/room-runtime/build.gradle
A room/room-runtime/src/nativeInterop/cinterop/sqliteSharedArchive.def
A room/room-runtime/src/nativeTest/kotlin/androidx.room/BuilderTest.kt
A room/room-runtime/src/nativeTest/kotlin/androidx.room/BuilderTest_TestDatabase_Impl.kt
A room/room-runtime/src/nativeTest/kotlin/androidx.room/BuilderTest_TestDatabase_InstantiateImpl.kt

https://android-review.googlesource.com/2888646

za...@gmail.com <za...@gmail.com> #4Apr 22, 2024 04:58AM

elifbilgin@google.com What do you think about using findAssociatedObject here?

el...@google.com <el...@google.com> #5Apr 22, 2024 06:23PM

Thanks for bringing this API to our attention! Looks like it could indeed be beneficial to help us avoid users referencing a generated function and make the factory lambda optional. We'll consider using it in our implementation - cheers!

ap...@google.com <ap...@google.com> #6Jul 15, 2024 07:23PM

Project: platform/frameworks/support
Branch: androidx-main

commit 19309786e1e720aebb977d0e73f21017156ae67d
Author: Daniel Santiago Rivera <danysantiago@google.com>
Date: Thu Jul 04 10:51:06 2024

Update Room initialization strategy for KMP

Changes Room reflection replacement strategy for KMP to one where Room generates an 'actual' implementations of an 'expect object' that is linked via an @AssociatedObjectKey annotated annotation in the @Database definition, that ultimately allows the builder; at runtime, to find the object, cast it to a known interface and invoke the generated override function that instantiates the generated database implementation.

Bug: 316978491
Bug: 338446862
Bug: 342905180
Test: ./gradlew :room:integration-tests:room-testapp-multiplatform:allTests

Relnote: """Changes the instantiation setup for a RoomDatabase in a KMP project.
Due to Kotlin 2.0 compilation model, the strategy of referencing a to-be-generated function, named 'instantiateImpl()' is longer viable. Two new APIs, @ConstructedBy and RoomDatabaseConstructor are introduced that replace the 'instantiateImpl()' strategy. The new strategy is as follow:

1. Define an expect object that implements RoomDatabaseConstructor
```
expect object MyDatabaseCtor : RoomDatabaseConstructor<MyDatabase>
```
2. Link the object with the @Database declaration using @ConstructedBy
```
@Database(...)
@ConstructedBy(MyDatabaseCtor::class) // NEW
abstract class MyDatabase : RoomDatabase
```
3. Create a new database instance but without passing a factory argument
```
fun createNewDatabase(path: String) =
Room.databaseBuilder<AppDatabase>(name = path)
.setDriver(BundledSQLiteDriver())
.setQueryCoroutineContext(Dispatchers.IO)
.build()
```
"""

Change-Id: Ic787a5c84f318dea0e004cd35efb2202bc6902dc

M room/integration-tests/multiplatformtestapp/build.gradle
M room/integration-tests/multiplatformtestapp/src/androidInstrumentedTest/kotlin/androidx/room/integration/multiplatformtestapp/test/BuilderTest.kt
M room/integration-tests/multiplatformtestapp/src/commonTest/kotlin/androidx/room/integration/multiplatformtestapp/test/BaseAutoMigrationTest.kt
M room/integration-tests/multiplatformtestapp/src/commonTest/kotlin/androidx/room/integration/multiplatformtestapp/test/BaseMigrationTest.kt
M room/integration-tests/multiplatformtestapp/src/commonTest/kotlin/androidx/room/integration/multiplatformtestapp/test/BaseTypeConverterTest.kt
M room/integration-tests/multiplatformtestapp/src/commonTest/kotlin/androidx/room/integration/multiplatformtestapp/test/SampleDatabase.kt
M room/integration-tests/multiplatformtestapp/src/jvmTest/kotlin/androidx/room/integration/multiplatformtestapp/test/BuilderTest.kt
M room/integration-tests/multiplatformtestapp/src/nativeTest/kotlin/androidx/room/integration/multiplatformtestapp/test/AutoMigrationTest.kt
M room/integration-tests/multiplatformtestapp/src/nativeTest/kotlin/androidx/room/integration/multiplatformtestapp/test/BuilderTest.kt
M room/integration-tests/multiplatformtestapp/src/nativeTest/kotlin/androidx/room/integration/multiplatformtestapp/test/InvalidationTest.kt
M room/integration-tests/multiplatformtestapp/src/nativeTest/kotlin/androidx/room/integration/multiplatformtestapp/test/MigrationTest.kt
M room/integration-tests/multiplatformtestapp/src/nativeTest/kotlin/androidx/room/integration/multiplatformtestapp/test/QueryTest.kt
M room/integration-tests/multiplatformtestapp/src/nativeTest/kotlin/androidx/room/integration/multiplatformtestapp/test/TypeConverterTest.kt
M room/room-common/api/current.txt
M room/room-common/api/restricted_current.txt
M room/room-common/bcv/native/current.txt
M room/room-common/build.gradle
A room/room-common/src/commonMain/kotlin/androidx/room/ConstructedBy.kt
M room/room-common/src/commonMain/kotlin/androidx/room/Database.kt
A room/room-common/src/jvmMain/kotlin/androidx/room/ConstructedBy.jvm.kt
A room/room-common/src/nativeMain/kotlin/androidx/room/ConstructedBy.native.kt
M room/room-compiler/src/main/kotlin/androidx/room/DatabaseProcessingStep.kt
M room/room-compiler/src/main/kotlin/androidx/room/ext/xpoet_ext.kt
M room/room-compiler/src/main/kotlin/androidx/room/processor/Context.kt
M room/room-compiler/src/main/kotlin/androidx/room/processor/DatabaseProcessor.kt
M room/room-compiler/src/main/kotlin/androidx/room/processor/ProcessorErrors.kt
M room/room-compiler/src/main/kotlin/androidx/room/vo/Database.kt
A room/room-compiler/src/main/kotlin/androidx/room/writer/DatabaseObjectConstructorWriter.kt
D room/room-compiler/src/main/kotlin/androidx/room/writer/InstantiateImplWriter.kt
A room/room-compiler/src/test/kotlin/androidx/room/processor/DatabaseConstructorProcessorTest.kt
M room/room-compiler/src/test/kotlin/androidx/room/verifier/DatabaseVerifierTest.kt
M room/room-compiler/src/test/kotlin/androidx/room/vo/DatabaseTest.kt
M room/room-compiler/src/test/kotlin/androidx/room/writer/DatabaseObjectConstructorWriterKotlinCodeGenTest.kt
A room/room-compiler/src/test/test-data/kotlinCodeGen/actualDatabaseConstructor.kt
D room/room-compiler/src/test/test-data/kotlinCodeGen/instantiateImpl_simple.kt
M room/room-gradle-plugin/src/test/test-data/multiplatform-project/src/commonMain/kotlin/room/testapp/CommonDatabase.kt
M room/room-gradle-plugin/src/test/test-data/multiplatform-project/src/jvmMain/kotlin/room/testapp/MyDatabase.kt
M room/room-gradle-plugin/src/test/test-data/multiplatform-project/src/nativeMain/kotlin/room/testapp/MyDatabase.kt
M room/room-runtime/api/current.txt
M room/room-runtime/api/restricted_current.txt
M room/room-runtime/bcv/native/current.txt
M room/room-runtime/src/androidMain/kotlin/androidx/room/Room.android.kt
A room/room-runtime/src/commonMain/kotlin/androidx/room/RoomDatabaseConstructor.kt
M room/room-runtime/src/jvmMain/kotlin/androidx/room/Room.jvm.kt
M room/room-runtime/src/nativeMain/kotlin/androidx/room/Room.native.kt
M room/room-runtime/src/nativeMain/kotlin/androidx/room/util/KClassUtil.native.kt
M room/room-testing/bcv/native/current.txt
M room/room-testing/src/nativeMain/kotlin/androidx/room/testing/MigrationTestHelper.native.kt

https://android-review.googlesource.com/3158707

pr...@google.com <pr...@google.com> #7Aug 13, 2024 06:58PM

The following release(s) address this bug.It is possible this bug has only been partially addressed:

androidx.room:room-common:2.7.0-alpha06
androidx.room:room-common-iosarm64:2.7.0-alpha06
androidx.room:room-common-iossimulatorarm64:2.7.0-alpha06
androidx.room:room-common-iosx64:2.7.0-alpha06
androidx.room:room-common-jvm:2.7.0-alpha06
androidx.room:room-common-linuxx64:2.7.0-alpha06
androidx.room:room-common-macosarm64:2.7.0-alpha06
androidx.room:room-common-macosx64:2.7.0-alpha06
androidx.room:room-compiler:2.7.0-alpha06
androidx.room:room-gradle-plugin:2.7.0-alpha06
androidx.room:room-runtime:2.7.0-alpha06
androidx.room:room-runtime-android:2.7.0-alpha06
androidx.room:room-runtime-iosarm64:2.7.0-alpha06
androidx.room:room-runtime-iossimulatorarm64:2.7.0-alpha06
androidx.room:room-runtime-iosx64:2.7.0-alpha06
androidx.room:room-runtime-jvm:2.7.0-alpha06
androidx.room:room-runtime-linuxx64:2.7.0-alpha06
androidx.room:room-runtime-macosarm64:2.7.0-alpha06
androidx.room:room-runtime-macosx64:2.7.0-alpha06
androidx.room:room-testing:2.7.0-alpha06
androidx.room:room-testing-android:2.7.0-alpha06
androidx.room:room-testing-iosarm64:2.7.0-alpha06
androidx.room:room-testing-iossimulatorarm64:2.7.0-alpha06
androidx.room:room-testing-iosx64:2.7.0-alpha06
androidx.room:room-testing-jvm:2.7.0-alpha06
androidx.room:room-testing-linuxx64:2.7.0-alpha06
androidx.room:room-testing-macosarm64:2.7.0-alpha06
androidx.room:room-testing-macosx64:2.7.0-alpha06

mi...@mercurydevelopment.com <mi...@mercurydevelopment.com> #8Aug 14, 2024 07:58AM

Is there a way now to use non-reflection initialization in a non-kmp project?

Since 2.7.0-alpha06 we don't have instantiateImpl anymore and can't use expect/actual in a non-kmp project to declare a subclass of RoomDatabaseConstructor.

da...@google.com <da...@google.com> #9Aug 14, 2024 01:03PM

If using Room in a JVM-only or Android-only project then @ConstructedBy is not required and there is no need to declare a 'expect' RoomDatabaseConstructor.

If you truly want to avoid reflection, then you can pass a factory to Room.databaseBuilder() that instantiates the generated implementation directly, but be warned, the name of the implementation is subject to change and not part of the public API.

Example:

// In a JVM only project

@Database(...)
abstract class SampleDatabase : RoomDatabase() {
  // ...
} 

fun getBuilder() =
    Room.inMemoryDatabaseBuilder<SampleDatabase>(
        factory = { SampleDatabase_Impl() }
    )