Android上的ProGuard和Gson(ClassCastException)

Question

我和Gson和ProGuard度过了一段难忘的时光.我有一个简单的对象,当我解析tojson时,保存到sqllite并从数据库读回以便将json加载回我的对象​​,我得到一个java.lang.classcastexception.如果我不使用ProGuard,everthing工作正常.

我已经验证了发送到数据库并从数据库获取的json字符串是相同的.从json转换时不会抛出异常,而是在我尝试访问对象时抛出异常.

这是我的简单对象:

public class ScanLog extends ArrayList<SingleFrame>
{
     private static final long serialVersionUID = 1L;

     public ScanLog()
     {

     }
}

public final class SingleFrame 
{
    public int Position;
    public int Time;
    public Map<Integer,String> MainDataMap;
    public Map<Integer,String> DataMap;

    public SingleFrame(int position, int time, 
                    Map<Integer,String> mainDataMap, Map<Integer,String> dataMap)
    {
        this.Position = position;
        this.Time = time;
        this.MainDataMap = mainDataMap;
        this.DataMap = dataMap;
    }

}

我的应用程序的所有其他方面都很好,但使用proguard导致这种情况发生....我已经在proguard.cfg中尝试了各种-keep命令,但我不确定我做的是对的.

编辑 - 添加PROGUARD.CFG

-dontusemixedcaseclassnames
-dontskipnonpubliclibraryclasses
-dontpreverify
-verbose
-dontshrink
-dontoptimize

-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

#keep all classes that might be used in XML layouts
-keep public class * extends android.view.View
-keep public class * extends android.app.Fragment
-keep public class * extends android.support.v4.Fragment

#keep all classes
-keep public class *{
public protected *;
}

#keep all public and protected methods that could be used by java reflection
-keepclassmembernames class * {
    public protected <methods>;
}


-keepclasseswithmembernames class * {
    native <methods>;
}

-keep public class org.scanner.scanlog.SingleFrame


-keepclassmembers class org.scanner.scanlog.ScanLog { 
        private <fields>; 
        public <fields>; 
}

-keepclassmembers class org.scanner.scanlog.SingleFrame { 
        private <fields>; 
        public <fields>; 
}

-keepclasseswithmembernames class * {
    public <init>(android.content.Context, android.util.AttributeSet);
}

-keepclasseswithmembernames class * {
    public <init>(android.content.Context, android.util.AttributeSet, int);
}

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

-keep class * implements android.os.Parcelable {
  public static final android.os.Parcelable$Creator *;
}

-dontwarn **CompatHoneycomb
-dontwarn org.htmlcleaner.*
#-keep class android.support.v4.** { *; }

编辑 - 好的,我在我的应用程序中成功设置了ACRA,非常棒的功能!这是堆栈跟踪:

java.lang.ClassCastException: java.lang.Object
    at org.scanner.activity.ReaderMainActivity.AdvanceScanLog(SourceFile:1499)
    at org.scanner.activity.r.onProgressChanged(SourceFile:271)
    at android.widget.SeekBar.onProgressRefresh(SeekBar.java:89)
    at android.widget.ProgressBar.doRefreshProgress(ProgressBar.java:507)
    at android.widget.ProgressBar.refreshProgress(ProgressBar.java:516)
    at android.widget.ProgressBar.setProgress(ProgressBar.java:565)
    at android.widget.AbsSeekBar.trackTouchEvent(AbsSeekBar.java:337)
    at android.widget.AbsSeekBar.onTouchEvent(AbsSeekBar.java:292)
    at android.view.View.dispatchTouchEvent(View.java:3932)
    at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:906)
    at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:906)
    at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:906)
    at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:906)
    at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:906)
    at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:906)
    at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:906)
    at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:906)
    at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:906)
    at com.android.internal.policy.impl.PhoneWindow$DecorView.superDispatchTouchEvent(PhoneWindow.java:1784)
    at com.android.internal.policy.impl.PhoneWindow.superDispatchTouchEvent(PhoneWindow.java:1157)
    at android.app.Activity.dispatchTouchEvent(Activity.java:2181)
    at com.android.internal.policy.impl.PhoneWindow$DecorView.dispatchTouchEvent(PhoneWindow.java:1759)
    at android.view.ViewRoot.deliverPointerEvent(ViewRoot.java:2336)
    at android.view.ViewRoot.handleMessage(ViewRoot.java:1976)
    at android.os.Handler.dispatchMessage(Handler.java:99)
    at android.os.Looper.loop(Looper.java:143)
    at android.app.ActivityThread.main(ActivityThread.java:4263)
    at java.lang.reflect.Method.invokeNative(Native Method)
    at java.lang.reflect.Method.invoke(Method.java:507)
    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
    at dalvik.system.NativeStart.main(Native Method)

Answer 1

有关推荐的proguard configuraiton文件的最新版本,请参阅gson提供的android proguard示例:https: //github.com/google/gson/blob/master/examples/android-proguard-example/proguard.cfg

Answer 2

配置中的这些设置适用于我的一个应用程序:

# Add the gson class
-keep public class com.google.gson

# Add any classes the interact with gson
-keep class com.someapp.android.models.ChatModel { *; }
-keep class com.someapp.android.models.FeedModel { *; }

# Add the path to the jar
-libraryjars /Users/someuser/Documents/workspace/someapp/lib/gson-1.7.1.jar

希望这会帮助你.

Answer 3

在Gson项目中应用Android示例中的更改对我有用

所需的线路是:

-keepattributes Signature
-keep class sun.misc.Unsafe { *; }
# and keeping the classes that will be serialized/deserialized

Answer 4

我知道原来的问题是通过采用不同的方法解决的,但我在Android上使用flexjson和Proguard时遇到了一个非常类似的问题,我已经解决了它,以防有人自己遇到它.

当从JSON转换回包含一些ArrayLists的值对象时,我会得到相同的ClassCastException.我通过基本上启用了混淆来实现工作,但是关闭了混淆的所有部分(保持一切,-keepclassmembers all和-keepattributes everything),然后通过一次启用一些东西来向后工作.

结果; 保留整个flexjson库:

-keep class flexjson**
--keepclassmembers class flexjson** {
   *;
}

并保留Signature和Annotation属性:

-keepattributes Signature, *Annotation*

在我的app的发布版本中,我能够使用flexjson库而不会发生任何事故.

Answer 5

看起来您确实保留了类中的所有内容（字段、方法和类本身）。但要确保您可以添加-printseeds outputfile.txt到 proguard.cfg 文件中，以验证混淆完成后 proguard 确实保留了您需要的所有内容。

顺便说一句，您可能会考虑添加类似ACRA 或 Android Remote stacktrace之类的东西，让您可以检查构建的应用程序上的堆栈跟踪。