java.lang.NoClassDefFoundError $$inlined$forEach$lambda$1 in Kotlin

Question

I am currently working on an Android application with Kotlin in version 1.1.1

In my code, I have imbrication of several forEach structures in order to read several MutableList and MutableMap.

Unfortunately, my app crashes with the following stacktrace :

java.lang.NoClassDefFoundError: com.package.fragment.ReminderAddFragment$onRetrieveBusinessObjects$$inlined$forEach$lambda$1 at com.package.fragment.ReminderAddFragment.onRetrieveBusinessObjects(ReminderAddFragment.kt:275) at com.smartnsoft.droid4me.app.Droid4mizer.onRetrieveBusinessObjects(Droid4mizer.java:552) at com.smartnsoft.droid4me.app.Droid4mizer.onRetrieveBusinessObjectsInternal(Droid4mizer.java:606) at com.smartnsoft.droid4me.app.Droid4mizer.access$000(Droid4mizer.java:46) at com.smartnsoft.droid4me.app.Droid4mizer$1.run(Droid4mizer.java:197) at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:423) at java.util.concurrent.FutureTask.run(FutureTask.java:237) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1113) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:588) at java.lang.Thread.run(Thread.java:818)

Here the code

tutorialCategories.forEach { (_, _, _, _, _, tutorials) ->   tutorials.forEach { tutorial ->     if (tutorial.id == simpleReminderFromExtra.tutorialId)     {       //...       val mapOfreminders = mutableMapOf<Int, MutableList<Reminder>>()       val reminders = ReminderServices.getReminderByTutorialId(simpleReminderFromExtra.tutorialId)        reminders.forEach { reminder ->         //...       }        mapOfreminders.forEach { _, finalReminders ->         //...          finalReminders.forEach { reminder ->           //...         }          //...       }     }   } } 

Where :

• tutorialCategories is a List ;
• tutorials is a List ;
• reminders is a List ;

The line 275 of the code is mapOfreminders.forEach { _, finalReminders ->.

In the debugger, I can evaluate the mapOfreminders variable and everything seems to be alright.

If someone can help to resolve this issue !

Answer 1

I encountered this problemjava.lang.NoClassDefFoundError on Android 6.0 and 6.0.1 by using

Map.forEach {key ,value -> } 

this call java 8 api.

And then, I solved this problem by adding brackets to parameter:

Map.forEach {(key ,value) -> } 

this call kotlin api

Answer 2

After reading Dan Lew's post a couple days ago, I'll make a suggestion that this can be caused by using Map.forEach { k, v -> } method from Java 8, which may be unavailable in Android runtime.

You could try to use another forEach with the single entry parameter that comes from the Kotlin standard library:

mapOfreminders.forEach { (_, finalReminders) -> } 

Here the parentheses are used to destructure entry parameter into two variables: ignored key and finalReminders value.