# Getting "java.lang.NullPointerException" while trying to join a meeting in the demo/sample app

**URL:** <https://devforum.zoom.us/t/getting-java-lang-nullpointerexception-while-trying-to-join-a-meeting-in-the-demo-sample-app/101450>\
**Category:** Meeting SDK\
**Created:** [January 9, 2024, 4:21am UTC](https://devforum.zoom.us/t/getting-java-lang-nullpointerexception-while-trying-to-join-a-meeting-in-the-demo-sample-app/101450 "2024-01-09T04:21:19Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![prathjain12](https://avatars.discourse-cdn.com/v4/letter/p/e0b2c6/32.png) [@prathjain12](https://devforum.zoom.us/u/prathjain12)\
**Post date:** [January 9, 2024, 4:21am UTC](https://devforum.zoom.us/t/getting-java-lang-nullpointerexception-while-trying-to-join-a-meeting-in-the-demo-sample-app/101450/1 "2024-01-09T04:21:19Z")

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Hi Team,

I am trying to run the sample android app from the given link,

> **[GitHub - zoom/zoom-sdk-android-getting-started](https://github.com/zoom/zoom-sdk-android-getting-started/)**
>
> Contribute to zoom/zoom-sdk-android-getting-started development by creating an account on GitHub.

I imported the latest commonlib and mobilertc, hence used the jwt token following the guidelines from here:

> **[How to create a sample JWT for the Meeting SDK](https://devsupport.zoom.us/hc/en-us/articles/360059893552-How-to-create-a-sample-JWT-for-the-Meeting-SDK)**
>
> The Zoom Meeting SDK uses JWT Web Tokens for authentication. The token is generated by the developer using the developer's SDK Key and Secret. This tutorial will guide you through creating a sample...

I am able to run the application, but when I am trying to join the meeting from the application, it is crashing, with following message :

FATAL EXCEPTION: main  
Process: com.example.basicdemoapp, PID: 11103  
java.lang.NullPointerException: Attempt to invoke interface method ‘int us.zoom.sdk.MeetingService.joinMeetingWithParams(android.content.Context, us.zoom.sdk.JoinMeetingParams, us.zoom.sdk.JoinMeetingOptions)’ on a null object reference  
at com.example.basicdemoapp.MainActivity.joinMeeting(MainActivity.kt:98)  
at com.example.basicdemoapp.MainActivity.createJoinMeetingDialog$lambda$8(MainActivity.kt:133)  
at com.example.basicdemoapp.MainActivity.$r8$lambda$2n9OoR3CUBIYxBJbYA9dGjQScwM(Unknown Source:0)  
at com.example.basicdemoapp.MainActivity$$ExternalSyntheticLambda0.onClick(Unknown Source:2)  
at androidx.appcompat.app.AlertController$ButtonHandler.handleMessage(AlertController.java:167)  
at android.os.Handler.dispatchMessage(Handler.java:106)  
at android.os.Looper.loopOnce(Looper.java:226)  
at android.os.Looper.loop(Looper.java:313)  
at android.app.ActivityThread.main(ActivityThread.java:8762)  
at java.lang.reflect.Method.invoke(Native Method)  
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:604)  
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1067)

please let me know if any thing else is require from my side to further investigate this incident.

Thank You

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**Author:** ![prathjain12](https://avatars.discourse-cdn.com/v4/letter/p/e0b2c6/32.png) [@prathjain12](https://devforum.zoom.us/u/prathjain12)\
**Post date:** [February 1, 2024, 4:30am UTC](https://devforum.zoom.us/t/getting-java-lang-nullpointerexception-while-trying-to-join-a-meeting-in-the-demo-sample-app/101450/2 "2024-02-01T04:30:28Z")

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Hi Team, any update on this ?

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**Author:** ![chunsiong.zoom](https://sea2.discourse-cdn.com/flex016/user_avatar/devforum.zoom.us/chunsiong.zoom/32/35488_2.png) [@chunsiong.zoom](https://devforum.zoom.us/u/chunsiong.zoom)\
**Post date:** [February 7, 2024, 1:15am UTC](https://devforum.zoom.us/t/getting-java-lang-nullpointerexception-while-trying-to-join-a-meeting-in-the-demo-sample-app/101450/3 "2024-02-07T01:15:49Z")

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@prathjain12 please download the latest SDK from [marketplace.zoom.us](http://marketplace.zoom.us)  
The SDK found on github is below the minimum version, and should not work.