GSON library problems on Android

[Joan Pujol]

Hi,

I started to have problems with GSON library in some clients after starting enableComplexMapKeySerialization

I get a java.lang.NoSuchMethodError: com.google.gson.GsonBuilder.enableComplexMapKeySerialization.

It's a very strange issue, because in only fails to a few users and the apk is the same for all.

Some one had this types of problems? Or knows if gson is integrated in some phone sdk and can make a version conflict using and older version that doesn't has enableComplexMapKeySerialization?

Any help will be greatly apreciated. A lot of thanks in advance,

[Jesse Wilson]

Looks like it could be related to our HTC-shipping-Gson bug:
http://code.google.com/p/google-gson/issues/detail?id=255

The easiest workaround is to use jarjar to give Gson a different
package name when you distribute in an Android app.
http://code.google.com/p/jarjar/

[Inderjeet Singh]

The best way to address this is by using proguard: 

This example explains how this can be done:

http://code.google.com/p/google-gson/source/browse/trunk/examples/android-proguard-example

Basically, you would add -keepattributes Signature

http://code.google.com/p/google-gson/source/browse/trunk/examples/android-proguard-example/proguard.cfg

Inder

----

My Android App: https://market.android.com/details?id=com.applimobile.spellmeright

[Jane Wu]

  i have tried your method on my proguard.cfg file 

but it seems that no use for my apps project 

and  below  is the  proguard file 

-optimizationpasses 5

-dontusemixedcaseclassnames

-dontskipnonpubliclibraryclasses

-dontpreverify

-verbose

-optimizations !code/simplification/arithmetic,!field/*,!class/merging/*

-keep public class * extends android.app.Activity

-keep public class * extends android.app.Application

-keep public class * extends android.app.Service

-keep public class * extends android.content.BroadcastReceiver

-keep public class * extends android.content.ContentProvider

-keep public class * extends android.app.backup.BackupAgentHelper

-keep public class * extends android.preference.Preference

-keep public class com.android.vending.licensing.ILicensingService

-keepclasseswithmembernames class * {

    native <methods>;

}

-keepclasseswithmembers class * {

    public <init>(android.content.Context, android.util.AttributeSet);

}

-keepclasseswithmembers class * {

    public <init>(android.content.Context, android.util.AttributeSet, int);

}

-keepclassmembers class * extends android.app.Activity {

   public void *(android.view.View);

}

-keepclassmembers enum * {

    public static **[] values();

    public static ** valueOf(java.lang.String);

}

-keep class * implements android.os.Parcelable {

  public static final android.os.Parcelable$Creator *;

}

-keepclassmembers class fully.qualified.path.to.class$innerclass { 

        private <fields>; 

}

##---------------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

this is my json class 

-keep class json.data.quickexpress.** { *; }

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

can  you  help me ?thank u !

  
在 2011年11月6日星期日UTC+8上午4时26分49秒，Inderjeet Singh写道：

[Ichigo Chan]

Hi, I have copy everything from that proguard.cfg file but after obfuscating Gson returns a list of null objects. For more information, please check out my question.

I

s this some new problem with ProGuard or Gson or am I missing something? I think I really need to obfuscate my code so please help me find the solution.

Thank you.

[Kasi Rajan M]

I'm also experiencing a similar problem as you've mentioned. Anyhow, a temporary (not so obfuscated) solution to this problem is by adding the following to your proguard configuration:

-keep public class * {
public protected *;
}

Not sure if it is worth taking the risk of leaving your classes and their members names not obfuscated but at least it works with custom TypeAdapters.