recently I finished building a big project in Android, and the last requirement before publish was that it will be compiled with Proguard enabled, which I thought will be the easy part in the project, but turned out to be quite of hellish experience for me.
In the project I used several third party libraries, at least from my current checking, it seems all of them are working fine with my Proguard config.
The problematic library is JWT: JSON Web Token for Java and Android, which doesn't have documentation about how to config it with Proguard, and I tried so many different configurations, but none solved this problem.
The error occurs only when I put this line in the code (calling a class from this library):
Jwts.builder();
And the error as follows:
java.lang.ExceptionInInitializerError at io.jsonwebtoken.Jwts.builder(ProGuard:116) at com.cineworld.app.screen_options.webpage.PurchaseWebPage.GenerateToken(ProGuard:216) at com.cineworld.app.screen_options.webpage.PurchaseWebPage.onCreateView(ProGuard:142) at android.app.Fragment.performCreateView(Fragment.java:1699) at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:885) at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:1057) at android.app.BackStackRecord.run(BackStackRecord.java:682) at android.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1435) at android.app.FragmentManagerImpl$1.run(FragmentManager.java:441) at android.os.Handler.handleCallback(Handler.java:725) at android.os.Handler.dispatchMessage(Handler.java:92) at android.os.Looper.loop(Looper.java:137) at android.app.ActivityThread.main(ActivityThread.java:5041) at java.lang.reflect.Method.invokeNative(Native Method) at java.lang.reflect.Method.invoke(Method.java:511) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560) at dalvik.system.NativeStart.main(Native Method) Caused by: java.lang.ExceptionInInitializerError at io.jsonwebtoken.impl.DefaultJwtBuilder.(ProGuard:42) at io.jsonwebtoken.Jwts.builder(ProGuard:116) at com.cineworld.app.screen_options.webpage.PurchaseWebPage.GenerateToken(ProGuard:216) at com.cineworld.app.screen_options.webpage.PurchaseWebPage.onCreateView(ProGuard:142) at android.app.Fragment.performCreateView(Fragment.java:1699) at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:885) at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:1057) at android.app.BackStackRecord.run(BackStackRecord.java:682) at android.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1435) at android.app.FragmentManagerImpl$1.run(FragmentManager.java:441) at android.os.Handler.handleCallback(Handler.java:725) at android.os.Handler.dispatchMessage(Handler.java:92) at android.os.Looper.loop(Looper.java:137) at android.app.ActivityThread.main(ActivityThread.java:5041) at java.lang.reflect.Method.invokeNative(Native Method) at java.lang.reflect.Method.invoke(Method.java:511) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560) at dalvik.system.NativeStart.main(Native Method) Caused by: java.lang.ExceptionInInitializerError at com.a.a.c.ad.(ProGuard:209) at io.jsonwebtoken.impl.DefaultJwtBuilder.(ProGuard:42) at io.jsonwebtoken.Jwts.builder(ProGuard:116) at com.cineworld.app.screen_options.webpage.PurchaseWebPage.GenerateToken(ProGuard:216) at com.cineworld.app.screen_options.webpage.PurchaseWebPage.onCreateView(ProGuard:142) at android.app.Fragment.performCreateView(Fragment.java:1699) at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:885) at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:1057) at android.app.BackStackRecord.run(BackStackRecord.java:682) at android.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1435) at android.app.FragmentManagerImpl$1.run(FragmentManager.java:441) at android.os.Handler.handleCallback(Handler.java:725) at android.os.Handler.dispatchMessage(Handler.java:92) at android.os.Looper.loop(Looper.java:137) at android.app.ActivityThread.main(ActivityThread.java:5041) at java.lang.reflect.Method.invokeNative(Native Method) at java.lang.reflect.Method.invoke(Method.java:511) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560) at dalvik.system.NativeStart.main(Native Method) Caused by: java.lang.NoSuchFieldError: PUBLIC_ONLY at java.lang.Class.getDeclaredAnnotation(Native Method) at java.lang.Class.getAnnotation(Class.java:260) at com.a.a.c.f.ac.(ProGuard:172) at com.a.a.c.ad.(ProGuard:209) at io.jsonwebtoken.impl.DefaultJwtBuilder.(ProGuard:42) at io.jsonwebtoken.Jwts.builder(ProGuard:116) at com.cineworld.app.screen_options.webpage.PurchaseWebPage.GenerateToken(ProGuard:216) at com.cineworld.app.screen_options.webpage.PurchaseWebPage.onCreateView(ProGuard:142) at android.app.Fragment.performCreateView(Fragment.java:1699) at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:885) at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:1057) at android.app.BackStackRecord.run(BackStackRecord.java:682) at android.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1435) at android.app.FragmentManagerImpl$1.run(FragmentManager.java:441) at android.os.Handler.handleCallback(Handler.java:725) at android.os.Handler.dispatchMessage(Handler.java:92) at android.os.Looper.loop(Looper.java:137) at android.app.ActivityThread.main(ActivityThread.java:5041) at java.lang.reflect.Method.invokeNative(Native Method) at java.lang.reflect.Method.invoke
Can someone guide me to the proper way to handle this problem?