Why am I getting a NoClassDefFoundError FATAL EXCEPTION in my AAA application?

After declaring a dependency on a AAA library and compiling an application, it is possible that the application will crash after issuing an error. e.g., you may see a stacktrace similar to this one:

04-02 10:23:30.621  1445  1445 W DeviceAAAListener: Init device AAA AuthenticationManager...
04-02 10:23:30.632  1445  1445 D AndroidRuntime: Shutting down VM
04-02 10:23:30.635  1445  1445 E AndroidRuntime: FATAL EXCEPTION: main
04-02 10:23:30.635  1445  1445 E AndroidRuntime: Process: com.fnord.app.aaaclient, PID: 1445
04-02 10:23:30.635  1445  1445 E AndroidRuntime: java.lang.NoClassDefFoundError: Failed resolution of: Lorg/slf4j/LoggerFactory;
04-02 10:23:30.635  1445  1445 E AndroidRuntime:     at com.ricoh.auth.manager.AAASmartSDKAuthenticationManager.<clinit>(AAASmartSDKAuthenticationManager.java:21)
04-02 10:23:30.635  1445  1445 E AndroidRuntime:     at com.fnord.app.aaaclient.application.DeviceAAAListener.Start(DeviceAAAListener.java:101)
04-02 10:23:30.635  1445  1445 E AndroidRuntime:     at com.fnord.app.aaaclient.MainActivity.onCreate(MainActivity.java:199)

The issue here is that AAA 2.1.0 has an internal dependency on SLF4J to provide a logging facade for any concrete logger you choose to use in your application, but this requirement was not made transitive. This has since been addressed in later releases of AAA.

The immediate solution is to make sure the dependency is added to your build configuration. For Gradle builds, something like this can be added to the dependencies closure:

implementation 'org.slf4j:slf4j-android:1.7.22'