如何解决“ java.lang.NoClassDefFoundError”？

Question

I am getting an error. Here is the log:

04-01 22:04:41.010: I/dalvikvm(19541): Could not find method com.quickblox.module.chat.smack.SmackAndroid.init, referenced from method com.quickblox.videochatsample.ui.App.onCreate
04-01 22:04:41.010: W/dalvikvm(19541): VFY: unable to resolve static method 13789: Lcom/quickblox/module/chat/smack/SmackAndroid;.init (Landroid/content/Context;)Lcom/quickblox/module/chat/smack/SmackAndroid;
04-01 22:04:41.010: D/dalvikvm(19541): VFY: replacing opcode 0x71 at 0x0003
04-01 22:04:41.010: D/AndroidRuntime(19541): Shutting down VM
04-01 22:04:41.010: W/dalvikvm(19541): threadid=1: thread exiting with uncaught exception (group=0x40c11a68)
04-01 22:04:41.020: E/AndroidRuntime(19541): FATAL EXCEPTION: main
04-01 22:04:41.020: E/AndroidRuntime(19541): java.lang.NoClassDefFoundError: com.quickblox.module.chat.smack.SmackAndroid
04-01 22:04:41.020: E/AndroidRuntime(19541):    at com.quickblox.videochatsample.ui.App.onCreate(App.java:13)
04-01 22:04:41.020: E/AndroidRuntime(19541):    at android.app.Instrumentation.callApplicationOnCreate(Instrumentation.java:973)
04-01 22:04:41.020: E/AndroidRuntime(19541):    at android.app.ActivityThread.handleBindApplication(ActivityThread.java:3971)
04-01 22:04:41.020: E/AndroidRuntime(19541):    at android.app.ActivityThread.access$1300(ActivityThread.java:128)
04-01 22:04:41.020: E/AndroidRuntime(19541):    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1199)
04-01 22:04:41.020: E/AndroidRuntime(19541):    at android.os.Handler.dispatchMessage(Handler.java:99)
04-01 22:04:41.020: E/AndroidRuntime(19541):    at android.os.Looper.loop(Looper.java:137)
04-01 22:04:41.020: E/AndroidRuntime(19541):    at android.app.ActivityThread.main(ActivityThread.java:4517)
04-01 22:04:41.020: E/AndroidRuntime(19541):    at java.lang.reflect.Method.invokeNative(Native Method)
04-01 22:04:41.020: E/AndroidRuntime(19541):    at java.lang.reflect.Method.invoke(Method.java:511)
04-01 22:04:41.020: E/AndroidRuntime(19541):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:993)
04-01 22:04:41.020: E/AndroidRuntime(19541):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:760)
04-01 22:04:41.020: E/AndroidRuntime(19541):    at dalvik.system.NativeStart.main(Native Method)  

Code:

package com.quickblox.videochatsample.ui;

import android.app.Application;

import com.quickblox.module.chat.smack.SmackAndroid;


public class App extends Application {

    @Override
    public void onCreate() {
        super.onCreate();
        SmackAndroid.init(this);
    }
}

Answer 1

A simple googling, and you will find the answer.

The answer is that your jar-file does not contain the proper jar-file, that contains the java class that you need.

If you do not use any build tool. Then I would suggest that you use that. So that you can tell the build tool to include that very important jar-file.

A build tool like ivy, maven, ant etc.

The reason why you can use that class when you code in your IDE. Is that the IDE for some reason have that jar-file/class in its classpath. But not on the build path. Why, it is hard to know since you have not shown your project file or equal file.

But I'm pretty sure you can solve the problem now.