android - 如何解决多个 D8 警告 : was not found, 它是 default 或静态接口(interface)方法 desugaring 所必需的？

Question

将 Android Gradle 插件从 3.1.4 升级到 3.2.x 后，我收到多个警告，例如:

D8: Type `com.google.gson.reflect.TypeToken` was not found, it is required for default or static interface methods desugaring of `com.google.gson.reflect.TypeToken org.springframework.http.converter.json.GsonHttpMessageConverter.getTypeToken(java.lang.reflect.Type)`
D8: Type `com.squareup.okhttp.MediaType` was not found, it is required for default or static interface methods desugaring of `com.squareup.okhttp.MediaType org.springframework.http.client.OkHttpClientHttpRequest.getContentType(org.springframework.http.HttpHeaders)`
D8: Type `org.apache.http.impl.client.HttpClients` was not found, it is required for default or static interface methods desugaring of `void org.springframework.http.client.HttpComponentsClientHttpRequestFactory.<init>()`
D8: Interface `org.apache.http.HttpEntity` not found. It's needed to make sure desugaring of `org.springframework.http.client.HttpComponentsStreamingClientHttpRequest$StreamingHttpEntity` is correct. Desugaring will assume that this interface has no default method.
D8: Type `org.conscrypt.Conscrypt` was not found, it is required for default or static interface methods desugaring of `okhttp3.internal.platform.Platform okhttp3.internal.platform.ConscryptPlatform.buildIfSupported()`
...

项目正在使用 Java 1.8 源兼容性 (lambdas)，看起来警告来自 Android gradle 类 dexer，它已在 AGP 3.2.0 中默认启用。

1. 我曾尝试使用以下行在 proguard-rules.pro 中抑制这些警告，但似乎没有任何效果。

   -dontwarn com.google.gson.reflect.TypeToken
   -keep class com.google.gson.reflect.TypeToken { *; }
   -dontwarn org.apache.http.**
   -keep class com.squareup.okhttp.** { *; }
   -dontwarn com.squareup.okhttp.**
   -keep class org.springframework.http.client.** { *; }
   -dontwarn org.springframework.http.client.**
   

2. 让警告消失的唯一方法是在 build 中将 minifyEnabled 和 useProguard 设置为 false .gradle 文件

3. 我尝试了 AGP 3.3.0-alpha13 和新的 AGP 3.2.1，但没有成功。

您可以使用来自 https://github.com/mdawid/D8WarningTest 的示例项目克隆存储库

Answer 1

更新:该问题已在 Android Gradle Plugin 3.5.0-beta05 中修复(参见问题:Ability to selectively suppress warnings during D8 desugaring)。

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对于 Android Gradle 插件 3.2.1 - 3.4.1，请使用以下解决方法:

来自 Android Gradle 插件 3.2.1 changelog :

Desugaring with D8 is now enabled by default.

所以你应该禁用 D8 的脱糖(在项目的 gradle.properties 文件中):

android.enableD8.desugaring=false

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如果您使用 R8:

R8 is a new tool for code shrinking and obfuscation that replaces ProGuard. You can start using the preview version of R8 by including the following in your project’s gradle.properties file:

android.enableR8 = true

禁用 R8 脱糖(在项目的 gradle.properties 文件中):

android.enableR8.desugaring=false