AGP 7+ / JDK 11 / 发布：ClassNotFoundException：在路径：DexPathList 上找不到 class“okhttp3.MultipartBody$Part”

Question

正如标题所说，自从我们更新到 Java 11 和 AGP 7+ 后，我在项目上遇到了一些问题。 该问题仅在发布时发生，当我们使用 okhttp3.MultipartBody 进行 retrofit 调用时：

2022-01-18 00:56:23.043 27908-27908/com.test.okhttpissue E/AndroidRuntime: FATAL EXCEPTION: main
    Process: com.test.okhttpissue, PID: 27908
    java.lang.TypeNotPresentException: Type okhttp3.MultipartBody$Part not present
        at libcore.reflect.ParameterizedTypeImpl.getRawType(ParameterizedTypeImpl.java:67)
        at libcore.reflect.ParameterizedTypeImpl.getResolvedType(ParameterizedTypeImpl.java:76)
        at libcore.reflect.GenericArrayTypeImpl.getGenericComponentType(GenericArrayTypeImpl.java:32)
        at j2.y.j(:362)
        at j2.s$a.j(:812)
        at j2.s$a.g(:626)
        at j2.s$a.f(:325)
        at j2.s$a.b(:206)
        at j2.s.b(:67)
        at j2.v.b(:26)
        at j2.u.c(:202)
        at j2.u$a.invoke(:160)
        at java.lang.reflect.Proxy.invoke(Proxy.java:1006)
        at $Proxy2.a(Unknown Source)
        at f1.a.a(:41)
        at com.test.okhttpissue.MainActivity.G(:30)
        at com.test.okhttpissue.MainActivity.F(Unknown Source:0)
        at f1.b.onClick(Unknown Source:0)
        at android.view.View.performClick(View.java:7259)
        at android.view.View.performClickInternal(View.java:7236)
        at android.view.View.access$3600(View.java:801)
        at android.view.View$PerformClick.run(View.java:27896)
        at android.os.Handler.handleCallback(Handler.java:883)
        at android.os.Handler.dispatchMessage(Handler.java:100)
        at android.os.Looper.loop(Looper.java:214)
        at android.app.ActivityThread.main(ActivityThread.java:7397)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:492)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:935)
     Caused by: java.lang.ClassNotFoundException: okhttp3.MultipartBody$Part
        at java.lang.Class.classForName(Native Method)
        at java.lang.Class.forName(Class.java:454)
        at libcore.reflect.ParameterizedTypeImpl.getRawType(ParameterizedTypeImpl.java:65)
        at libcore.reflect.ParameterizedTypeImpl.getResolvedType(ParameterizedTypeImpl.java:76) 
        at libcore.reflect.GenericArrayTypeImpl.getGenericComponentType(GenericArrayTypeImpl.java:32) 
        at j2.y.j(:362) 
        at j2.s$a.j(:812) 
        at j2.s$a.g(:626) 
        at j2.s$a.f(:325) 
        at j2.s$a.b(:206) 
        at j2.s.b(:67) 
        at j2.v.b(:26) 
        at j2.u.c(:202) 
        at j2.u$a.invoke(:160) 
        at java.lang.reflect.Proxy.invoke(Proxy.java:1006) 
        at $Proxy2.a(Unknown Source) 
        at f1.a.a(:41) 
        at com.test.okhttpissue.MainActivity.G(:30) 
        at com.test.okhttpissue.MainActivity.F(Unknown Source:0) 
        at f1.b.onClick(Unknown Source:0) 
        at android.view.View.performClick(View.java:7259) 
        at android.view.View.performClickInternal(View.java:7236) 
        at android.view.View.access$3600(View.java:801) 
        at android.view.View$PerformClick.run(View.java:27896) 
        at android.os.Handler.handleCallback(Handler.java:883) 
        at android.os.Handler.dispatchMessage(Handler.java:100) 
        at android.os.Looper.loop(Looper.java:214) 
        at android.app.ActivityThread.main(ActivityThread.java:7397) 
        at java.lang.reflect.Method.invoke(Native Method) 
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:492) 
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:935) 
     Caused by: java.lang.ClassNotFoundException: Didn't find class "okhttp3.MultipartBody$Part" on path: DexPathList[[zip file "/data/app/com.test.okhttpissue-pBclZ8Dcl_TuV_j7iAp7oA==/base.apk"],nativeLibraryDirectories=[/data/app/com.test.okhttpissue-pBclZ8Dcl_TuV_j7iAp7oA==/lib/arm64, /system/lib64, /system/product/lib64]]
        at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:196)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:379)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:312)
        at java.lang.Class.classForName(Native Method) 
        at java.lang.Class.forName(Class.java:454) 
        at libcore.reflect.ParameterizedTypeImpl.getRawType(ParameterizedTypeImpl.java:65) 
        at libcore.reflect.ParameterizedTypeImpl.getResolvedType(ParameterizedTypeImpl.java:76) 
        at libcore.reflect.GenericArrayTypeImpl.getGenericComponentType(GenericArrayTypeImpl.java:32) 
        at j2.y.j(:362) 
        at j2.s$a.j(:812) 
        at j2.s$a.g(:626) 
        at j2.s$a.f(:325) 
        at j2.s$a.b(:206) 
        at j2.s.b(:67) 
        at j2.v.b(:26) 
        at j2.u.c(:202) 
        at j2.u$a.invoke(:160) 
        at java.lang.reflect.Proxy.invoke(Proxy.java:1006) 
        at $Proxy2.a(Unknown Source) 
        at f1.a.a(:41) 
        at com.test.okhttpissue.MainActivity.G(:30) 
        at com.test.okhttpissue.MainActivity.F(Unknown Source:0) 
        at f1.b.onClick(Unknown Source:0) 
        at android.view.View.performClick(View.java:7259) 
        at android.view.View.performClickInternal(View.java:7236) 
        at android.view.View.access$3600(View.java:801) 
        at android.view.View$PerformClick.run(View.java:27896) 
        at android.os.Handler.handleCallback(Handler.java:883) 
        at android.os.Handler.dispatchMessage(Handler.java:100) 
        at android.os.Looper.loop(Looper.java:214) 
        at android.app.ActivityThread.main(ActivityThread.java:7397) 
        at java.lang.reflect.Method.invoke(Native Method) 
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:492) 
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:935) 
2022-01-18 00:56:23.074 27908-27908/com.test.okhttpissue I/Process: Sending signal. PID: 27908 SIG: 9

AGP 4.2.2 / Java 1.8 上不会出现此问题。

我能够在具有以下配置的基本示例应用程序中重现它：

plugins {
    id 'com.android.application'
    id 'kotlin-android'
}

android {
    compileSdkVersion 30

    defaultConfig {
        applicationId "com.test.okhttpissue"
        minSdk 24
        targetSdk 29
        versionCode 1
        versionName "1.0"
        proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'

        testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
    }

    buildTypes {
        release {
            signingConfig signingConfigs.debug
            debuggable true
            minifyEnabled true
            shrinkResources true
            zipAlignEnabled true
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
    compileOptions {
        sourceCompatibility JavaVersion.VERSION_11
        targetCompatibility JavaVersion.VERSION_11
    }

    kotlinOptions {
        jvmTarget = JavaVersion.VERSION_11.toString()
    }
    buildFeatures {
        viewBinding true
    }
}

dependencies {
    implementation 'androidx.appcompat:appcompat:1.1.0'
    implementation 'com.google.android.material:material:1.0.0'
    implementation 'androidx.constraintlayout:constraintlayout:1.1.3'

    implementation "io.reactivex.rxjava3:rxjava:3.1.3"
    implementation 'io.reactivex.rxjava3:rxandroid:3.0.0'
    implementation "com.squareup.retrofit2:adapter-rxjava3:2.9.0"
    implementation "com.squareup.retrofit2:retrofit:2.9.0"
    implementation "com.squareup.retrofit2:converter-gson:2.9.0"
}

以下代码段：

class IssueDemo {

    val testApi: TestApi by lazy {
        Retrofit.Builder()
            .baseUrl("https://google.com")
            .client(OkHttpClient().newBuilder().build())
            .addCallAdapterFactory(RxJava3CallAdapterFactory.createWithScheduler(Schedulers.io()))
            .addConverterFactory(GsonConverterFactory.create())
            .build()
            .create(TestApi::class.java)
    }

    interface TestApi {

        @Multipart
        @POST("test/files")
        fun uploadMultipleFiles(@Part files: Array<MultipartBody.Part?>): Single<String>
    }

    fun execute() {
        val file = File("")
        val requestFile: RequestBody =
            RequestBody.create(MediaType.parse("multipart/form-data"), file)
        val test = MultipartBody.Part.createFormData("nameFormData", file.name, requestFile)
        testApi.uploadMultipleFiles(arrayOf(test))
    }
}

我尝试了很多东西，但到目前为止似乎唯一可以解决的问题是添加一个 proguard 规则-keep class okhttp3.MultipartBody但感觉不对。 在 AGP 4.2.2 中，它已经在使用 R8 和与库捆绑的 proguard 规则，那么为什么我们突然需要另一个特定规则来仅针对该库的一个 class 呢？

编辑：似乎从Array<MultipartBody.Part?>切换到List<MultipartBody.Part?> ，而不触及任何 proguard 规则，解决了这个问题。 有人明白会发生什么吗？

Answer 1

R8 可能无法检测到正在使用的 class，因为它可能被反射调用。 如果是这种情况，您必须在 proguard-project.txt 中添加显式保留规则。