Proguard 난독 화를 사용할 때 Gson EnumTypeAdapter의 AssertionError

Proguard 난독 화를 사용할 때 Gson EnumTypeAdapter의 AssertionError

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내 프로젝트는 객체의 다형성 상태를 보존하기 위해 직렬화 / 역 직렬화 중에 TypeAdapterin을 구현합니다 Gson. 어쨌든 프로젝트는 개발 테스트 중에 잘 작동하지만 proguard 난독 화로 출시 되고 테스트되면 충돌이 발생합니다.

03-21 10:06:53.632: E/AndroidRuntime(12441): FATAL EXCEPTION: main
03-21 10:06:53.632: E/AndroidRuntime(12441): java.lang.AssertionError
03-21 10:06:53.632: E/AndroidRuntime(12441):    at com.google.gson.internal.bind.TypeAdapters$EnumTypeAdapter.<init>(SourceFile:724)
03-21 10:06:53.632: E/AndroidRuntime(12441):    at com.google.gson.internal.bind.TypeAdapters$26.create(SourceFile:753)
03-21 10:06:53.632: E/AndroidRuntime(12441):    at com.google.gson.Gson.getAdapter(SourceFile:353)
03-21 10:06:53.632: E/AndroidRuntime(12441):    at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory$1.<init>(SourceFile:82)
03-21 10:06:53.632: E/AndroidRuntime(12441):    at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory.createBoundField(SourceFile:81)
03-21 10:06:53.632: E/AndroidRuntime(12441):    at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory.getBoundFields(SourceFile:118)
03-21 10:06:53.632: E/AndroidRuntime(12441):    at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory.create(SourceFile:72)
03-21 10:06:53.632: E/AndroidRuntime(12441):    at com.google.gson.Gson.getAdapter(SourceFile:353)
03-21 10:06:53.632: E/AndroidRuntime(12441):    at com.google.gson.Gson.toJson(SourceFile:578)
03-21 10:06:53.632: E/AndroidRuntime(12441):    at com.google.gson.Gson.toJsonTree(SourceFile:479)
03-21 10:06:53.632: E/AndroidRuntime(12441):    at com.google.gson.Gson.toJsonTree(SourceFile:458)
03-21 10:06:53.632: E/AndroidRuntime(12441):    at com.google.gson.Gson$3.serialize(SourceFile:137)

내 Gson 특정 proguard 구성은 다음과 같습니다.

##---------------Begin: proguard configuration for Gson  ----------
# Gson uses generic type information stored in a class file when working with fields. Proguard
# removes such information by default, so configure it to keep all of it.
-keepattributes Signature

# For using GSON @Expose annotation
-keepattributes *Annotation*

# Gson specific classes
-keep class sun.misc.Unsafe { *; }
#-keep class com.google.gson.stream.** { *; }

# Application classes that will be serialized/deserialized over Gson
-keep class com.google.gson.examples.android.model.** { *; }

#This is extra - added by me to exclude gson obfuscation
-keep class com.google.gson.** { *; }

##---------------End: proguard configuration for Gson  ----------

TypeAdapter 내가 사용은 다음과 같습니다

public final class GsonWorkshiftAdapter implements JsonSerializer<IWorkshift>, JsonDeserializer<IWorkshift> {
    private static final String CLASSNAME = "CLASSNAME";
    private static final String INSTANCE  = "INSTANCE";

    @Override
    public JsonElement serialize(IWorkshift src, Type typeOfSrc, JsonSerializationContext context) {
        String className = src.getClass().getCanonicalName();
        JsonElement elem = context.serialize(src);

        JsonObject retValue = new JsonObject();
        retValue.addProperty(CLASSNAME, className);
        retValue.add(INSTANCE, elem);

        return retValue;
    }

    @Override
    public IWorkshift deserialize(JsonElement json, Type typeOfT, JsonDeserializationContext context) throws JsonParseException {
        JsonObject jsonObject =  json.getAsJsonObject();
        JsonPrimitive prim = (JsonPrimitive) jsonObject.get(CLASSNAME);
        String className = prim.getAsString();

        Class<?> klass = null;
        try { klass = Class.forName(className); }
        catch (ClassNotFoundException e) { throw new JsonParseException(e.getMessage()); }

        return context.deserialize(jsonObject.get(INSTANCE), klass);
    }
}

Gson과 관련된이 오류에 대해 많은 검색을 수행했지만 유용한 답변을 찾을 수 없습니다. 그러나 비슷한 문제로 또 다른 질문 을 찾았습니다 .

개발자 커뮤니티의 도움을 주시면 감사하겠습니다.

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열거 형의 멤버를 유지하도록 요청해야하는 것 같습니다. 이것을 proguard 구성 파일에 추가하면 저에게 효과적이었습니다.

-keepclassmembers enum * { *; }

Or, if you want to be more specific,

-keepclassmembers enum com.your.package.** { *; }

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GSON throws this AssertionError when it fails to deserialize enumeration constants from JSON data, performing introspection on the fields of the enum class. Unfortunately, it swallows the details of the underlying NoSuchFieldException.

You should make sure that you preserve the names of the enum fields (and of fields in general) that are serialized. By default, ProGuard may rename or even remove them. For instance, with some wildcards:

-keepclassmembers class com.example.domain.** {
    <fields>;
}

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It is already suggested that you need to configure Proguard in a way that it keeps every enum related to serialized objects intact. I don't really like the fact that I have to explicitly list all my enums, this solution is hard to maintain. A slightly better solution I came up with is the following.

Use an empty interface to indicate that a class or enum takes part in Gson serialization:

public interface GsonSerializable { }

public class MyClass implements GsonSerializable {

    public enum MyEnum implements GsonSerializable {
        enumvalue1, enumvalue2
    }

    public MyEnum mydata1;
}

Use a Proguard config that keeps both the interface and all classes/enums that implement it:

# keep GsonSerializable interface, it would be thrown away by proguard since it is empty
-keep class com.example.GsonSerializable

# member fields of serialized classes, including enums that implement this interface
-keepclassmembers class * implements com.example.GsonSerializable {
    <fields>;
}

# also keep names of these classes. not required, but just in case.
-keepnames class * implements com.example.GsonSerializable

That's it, as long as your classes and enums use the interface, you should be OK. You could also enforce the presence of this interface in your serialization/deserialization methods, so you don't forget it when adding a new class later:

public String serializeWithGson(GsonSerializable object) { ... }

Also in your configuration the line with 'com.google.gson.examples.android.model.** { *; }' refers to some Google related example code, so I don't think it is necessary.

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After running into the same problem, I went through and examined the resulting APK decompiled. I believe the problem is related to some enum type losing its members during obfuscation.

Be sure to keep enums:

 -keepclassmembers enum * {
     public static **[] values();
     public static ** valueOf(java.lang.String);
 }

Also - make sure ALL of the classes being used in GSON are being retained:

 -keep public class com.company.ordering.datacontract.** {
     public protected *;
 }

 -keep public class com.company.ordering.service.request.** {
     public protected *;
 }
 -keep public class com.company.ordering.service.response.** {
     public protected *;
 }

See full config @ pastebin.com/r5Jg3yY2

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In my case, proguard was configured to -keep individual classes touched by Gson, but the error went away when I configured proguard to retain the package where those individual classes resided:

-keep class com.company.library.model.** { *; }

참고URL : https://stackoverflow.com/questions/15543607/assertionerror-in-gson-enumtypeadapter-when-using-proguard-obfuscation