Kotlin错误之java.lang.ClassNotFoundException

遇到的错误：

                                                                           Process: com.yunzhi.communitymanager, PID: 7459
                                                                           java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.yunzhi.communitymanager/com.yunzhi.communitymanager.activity.MainActivity}: java.lang.ClassNotFoundException: Didn't find class "com.yunzhi.communitymanager.activity.MainActivity" on path: DexPathList[[zip file "/system/framework/org.apache.http.legacy.boot.jar", zip file "/data/app/com.yunzhi.communitymanager-OqjAYeqjkRc5T8jlJKcOrQ==/base.apk"],nativeLibraryDirectories=[/data/app/com.yunzhi.communitymanager-OqjAYeqjkRc5T8jlJKcOrQ==/lib/x86_64, /system/lib64]]
                                                                               at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2843)
                                                                               at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3048)
                                                                               at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:78)
                                                                               at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:108)
                                                                               at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:68)
                                                                               at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1808)
                                                                               at android.os.Handler.dispatchMessage(Handler.java:106)
                                                                               at android.os.Looper.loop(Looper.java:193)
                                                                               at android.app.ActivityThread.main(ActivityThread.java:6669)
                                                                               at java.lang.reflect.Method.invoke(Native Method)
                                                                               at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493)
                                                                               at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:858)
                                                                            Caused by: java.lang.ClassNotFoundException: Didn't find class "com.yunzhi.communitymanager.activity.MainActivity" on path: DexPathList[[zip file "/system/framework/org.apache.http.legacy.boot.jar", zip file "/data/app/com.yunzhi.communitymanager-OqjAYeqjkRc5T8jlJKcOrQ==/base.apk"],nativeLibraryDirectories=[/data/app/com.yunzhi.communitymanager-OqjAYeqjkRc5T8jlJKcOrQ==/lib/x86_64, /system/lib64]]
                                                                               at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:134)
                                                                               at java.lang.ClassLoader.loadClass(ClassLoader.java:379)
                                                                               at java.lang.ClassLoader.loadClass(ClassLoader.java:312)
                                                                               at android.app.AppComponentFactory.instantiateActivity(AppComponentFactory.java:69)
                                                                               at android.app.Instrumentation.newActivity(Instrumentation.java:1215)
                                                                               at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2831)
                                                                               at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3048) 
                                                                               at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:78) 
                                                                               at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:108) 
                                                                               at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:68) 
                                                                               at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1808) 
                                                                               at android.os.Handler.dispatchMessage(Handler.java:106) 
                                                                               at android.os.Looper.loop(Looper.java:193) 
                                                                               at android.app.ActivityThread.main(ActivityThread.java:6669) 
                                                                               at java.lang.reflect.Method.invoke(Native Method) 
                                                                               at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493) 
                                                                               at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:858) 

项目结构：

app依赖common，且app中用kotlin编码

错误原因：

本以为在common中添加了kotlin插件就可以了，但是一运行就报错。最后再app中添加kotlin插件就好了。