Question

I am developing one android application and in that app I am trying to use Gson Library for Json serialization and de-serialization. I downloaded the library from the following link:-

http://code.google.com/p/google-gson/downloads/list

I included the gson-2.2.2.jar in Java Build Path, but the application crashes at run time when constructing Gson object:-

Gson gson = new Gson();

in logcat I get

07-24 14:53:21.648: E/dalvikvm(488): Could not find class 'com.google.gson.Gson', referenced from method com.google.gson.examples.android.GsonProguardExampleActivity.onCreate
07-24 14:53:21.648: W/dalvikvm(488): VFY: unable to resolve new-instance 10 (Lcom/google/gson/Gson;) in Lcom/google/gson/examples/android/GsonProguardExampleActivity;
07-24 14:53:21.668: D/dalvikvm(488): VFY: replacing opcode 0x22 at 0x0010
07-24 14:53:21.668: D/dalvikvm(488): VFY: dead code 0x0012-007a in Lcom/google/gson/examples/android/GsonProguardExampleActivity;.onCreate (Landroid/os/Bundle;)V
07-24 14:53:21.788: D/AndroidRuntime(488): Shutting down VM
07-24 14:53:21.788: W/dalvikvm(488): threadid=1: thread exiting with uncaught exception (group=0x4001d800)
07-24 14:53:21.814: E/AndroidRuntime(488): FATAL EXCEPTION: main
07-24 14:53:21.814: E/AndroidRuntime(488): java.lang.NoClassDefFoundError: com.google.gson.Gson
07-24 14:53:21.814: E/AndroidRuntime(488):  at com.google.gson.examples.android.GsonProguardExampleActivity.onCreate(GsonProguardExampleActivity.java:40)
07-24 14:53:21.814: E/AndroidRuntime(488):  at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
07-24 14:53:21.814: E/AndroidRuntime(488):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2627)
07-24 14:53:21.814: E/AndroidRuntime(488):  at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2679)
07-24 14:53:21.814: E/AndroidRuntime(488):  at android.app.ActivityThread.access$2300(ActivityThread.java:125)
07-24 14:53:21.814: E/AndroidRuntime(488):  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2033)
07-24 14:53:21.814: E/AndroidRuntime(488):  at android.os.Handler.dispatchMessage(Handler.java:99)
07-24 14:53:21.814: E/AndroidRuntime(488):  at android.os.Looper.loop(Looper.java:123)
07-24 14:53:21.814: E/AndroidRuntime(488):  at android.app.ActivityThread.main(ActivityThread.java:4627)
07-24 14:53:21.814: E/AndroidRuntime(488):  at java.lang.reflect.Method.invokeNative(Native Method)
07-24 14:53:21.814: E/AndroidRuntime(488):  at java.lang.reflect.Method.invoke(Method.java:521)
07-24 14:53:21.814: E/AndroidRuntime(488):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
07-24 14:53:21.814: E/AndroidRuntime(488):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
07-24 14:53:21.814: E/AndroidRuntime(488):  at dalvik.system.NativeStart.main(Native Method)

Error is:-

07-24 14:53:21.814: E/AndroidRuntime(488): java.lang.NoClassDefFoundError: com.google.gson.Gson

Also, If I include full source of Gson library as another package in my project it all works well.

What am I doing wrong, is this the correct jar??

Answer 1

Seems you have kept the jar file inside lib folder, rather the name should be changed to libs. This was updated newer revisions of ADT (revision 17 onwards).