Android app crashes when Proguard is enabled

Question

Every time I Export Signed Application from eclipse and install the apk file onto my phone, the app would crash. This only happens with Proguard enabled.

Here is my proguard file

-libraryjars /libs/firebase-client-android-2.2.3.jar
-libraryjars /libs/android-support-v4.jar
-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
-keep public class * implements java.io.Serializable
-keep public class * extends android.support.v4.app.Fragment
-keep public class * extends android.support.v4.app.ListFragment

-dontwarn com.shaded.fasterxml.**
-dontwarn org.apache.**
-dontwarn org.shaded.apache.**
-keepnames class com.shaded.fasterxml.jackson.** { *; }
-keepnames class org.shaded.apache.**

-keepnames interface com.fasterxml.jackson.** { 
    *; 
}

-keep public class * extends com.android.partysearch.ChatApplication
-keepclassmembers class * extends com.android.partysearch.ChatApplication{
 public <init>(android.content.Context);
}


-keep public class org.spongycastle.** {
  <fields>;
  <methods>;
}

-keep public class org.apache.** {
  <fields>;
  <methods>;
}

-ignorewarnings

-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 * implements java.io.Serializable {
    static final long serialVersionUID;
    private static final java.io.ObjectStreamField[] serialPersistentFields;
    private void writeObject(java.io.ObjectOutputStream);
    private void readObject(java.io.ObjectInputStream);
    java.lang.Object writeReplace();
    java.lang.Object readResolve();
}

I ran the adb logcat command to check the crash report. Here's a snippet of the report that I believe is important:

E/AndroidRuntime(28630): Caused by: java.lang.RuntimeException: Something went wrong, please report to support@firebase.com
E/AndroidRuntime(28630):    at com.firebase.client.core.h.a(Unknown Source)
E/AndroidRuntime(28630):    at com.firebase.client.g.a(Unknown Source)
E/AndroidRuntime(28630):    at com.partysearch.ChatApplication.onCreate(Unknown Source)
E/AndroidRuntime(28630):    at android.app.Instrumentation.callApplicationOnCreate(Instrumentation.java:1024)
E/AndroidRuntime(28630):    at android.app.ActivityThread.handleBindApplication(ActivityThread.java:4694)
E/AndroidRuntime(28630):    ... 10 more
E/AndroidRuntime(28630): Caused by: java.lang.NoSuchMethodException: <init> [class android.content.Context]
E/AndroidRuntime(28630):    at java.lang.Class.getConstructorOrMethod(Class.java:423)
E/AndroidRuntime(28630):    at java.lang.Class.getConstructor(Class.java:397)
E/AndroidRuntime(28630):    ... 15 more

2nd snippet:

W/System.err(  356): Caused by: libcore.io.ErrnoException: open failed: ENOENT (No such file or directory)
W/System.err(  356):    at libcore.io.Posix.open(Native Method)
W/System.err(  356):    at libcore.io.BlockGuardOs.open(BlockGuardOs.java:110)
W/System.err(  356):    at libcore.io.IoBridge.open(IoBridge.java:393)
W/System.err(  356):    ... 8 more

If anyone can help me, I would be very be thankful and accept your answer.

UPDATE: So I added these to my proguard file

-keepattributes Signature
-keep class com.firebase.** { *; }
-keep class org.apache.** { *; }
-keepnames class javax.servlet.** { *; }
-keepnames class org.ietf.jgss.** { *; }
-dontwarn org.w3c.dom.**
-dontwarn org.joda.time.**
-dontwarn org.ietf.jgss.**

and now I got an error related to Jackson when Proguard is enabled. The app still works if Proguard is disabled. Here's the snippet of the crash log:

E/AndroidRuntime( 6032): Caused by: com.shaded.fasterxml.jackson.databind.exc.UnrecognizedPropertyException: Unrecognized field "time" (class com.partysearch.Room), not marked as ignorable (5 known properties: , "note", "level", "userName", "console", "gametype"])

E/AndroidRuntime( 6032):  at [Source: java.io.StringReader@42664098; line: 1, column: 51] (through reference chain: com.partysearch.Room["time"])

E/AndroidRuntime( 6032):    at com.shaded.fasterxml.jackson.databind.DeserializationContext.reportUnknownProperty(DeserializationContext.java:555)

E/AndroidRuntime( 6032):    at com.shaded.fasterxml.jackson.databind.deser.std.StdDeserializer.handleUnknownProperty(StdDeserializer.java:708)

E/AndroidRuntime( 6032):    at com.shaded.fasterxml.jackson.databind.deser.BeanDeserializerBase.handleUnknownProperty(BeanDeserializerBase.java:1160)

E/AndroidRuntime( 6032):    at com.shaded.fasterxml.jackson.databind.deser.BeanDeserializer.deserializeFromObject(BeanDeserializer.java:315)

E/AndroidRuntime( 6032):    at com.shaded.fasterxml.jackson.databind.deser.BeanDeserializer.deserialize(BeanDeserializer.java:121)

E/AndroidRuntime( 6032):    at com.shaded.fasterxml.jackson.databind.ObjectMapper._readMapAndClose(ObjectMapper.java:2888)

E/AndroidRuntime( 6032):    at com.shaded.fasterxml.jackson.databind.ObjectMapper.readValue(ObjectMapper.java:2034)

E/AndroidRuntime( 6032):    at com.firebase.client.DataSnapshot.getValue(DataSnapshot.java:184)

E/AndroidRuntime( 6032):    ... 13 more

Answer 1

Just add -keep class com.firebase.**{ *; } in your proguard-rules.pro file.

Answer 2

I finally solved it. This is what I forgot to add to my Proguard file. The getters and setters.

-keep public class com.example.YourModelClassName {
  public *** get*();
  public void set*(***);
} 

Answer 3

I would venture to guess something in your app is using Java reflection to instantiate a class.

It appears whatever class this is has been name-mangled by proguard.

You'll have to figure out which one and add an exception rule for it.

You can make use of the mapping file proguard creates to figure out which class and method is being used in the exception. The file is located in build/outputs/proguard/release/mapping.txt