UrsAI2PahoMqtt Java Error in App inventor

[raywong]

Hi there, I tried to import UrsPahoMqttClient extension (Ullis Roboter Seite/AI2 MQTT) for my MQTT project and I always got the following error message (This message appears when I imported it or when I connected to USB)
I am using Chrome 109.0.5414.120. Windows 11 Home 22H2, Java Version 8 update 361, MIT AI 2 Companion 2.65 and AI starter tools. I have been stuck for this error few days....please help

Error from Companion: java.lang.RuntimeException: invalid syntax in eval form: :17:1: caught exception in inliner for # - java.lang.RuntimeException: no such class: de.ullisroboterseite.ursai2pahomqtt.UrsPahoMqttClient gnu.bytecode.ObjectType.getReflectClass(ObjectType.java:179) gnu.bytecode.ClassType.getModifiers(ClassType.java:103) gnu.bytecode.ClassType.isInterface(ClassType.java:471) gnu.expr.InlineCalls.checkType(InlineCalls.java:56) gnu.expr.InlineCalls.visit(InlineCalls.java:49) gnu.expr.InlineCalls.visitSetExpValue(InlineCalls.java:363) gnu.expr.InlineCalls.visitSetExpValue(InlineCalls.java:28) gnu.expr.ExpVisitor.visitSetExp(ExpVisitor.java:114) gnu.expr.InlineCalls.visitSetExp(InlineCalls.java:369) gnu.expr.InlineCalls.visitSetExp(InlineCalls.java:28) gnu.expr.SetExp.visit(SetExp.java:406) gnu.expr.ExpVisitor.visit(ExpVisitor.java:55) gnu.expr.InlineCalls.visit(InlineCalls.java:46) gnu.expr.InlineCalls.visitBeginExp(InlineCalls.java:272) gnu.expr.InlineCalls.visitBeginExp(InlineCalls.java:28) gnu.expr.BeginExp.visit(BeginExp.java:156) gnu.expr.ExpVisitor.visit(ExpVisitor.java:51) gnu.expr.InlineCalls.visit(InlineCalls.java:46) gnu.expr.InlineCalls.visitBeginExp(InlineCalls.java:272) gnu.expr.InlineCalls.visitBeginExp(InlineCalls.java:28) gnu.expr.BeginExp.visit(BeginExp.java:156) gnu.expr.ExpVisitor.visit(ExpVisitor.java:51) gnu.expr.InlineCalls.visit(InlineCalls.java:46) gnu.expr.InlineCalls.visitLetExp(InlineCalls.java:317) gnu.expr.InlineCalls.visitLetExp(InlineCalls.java:28) gnu.expr.LetExp.visit(LetExp.java:207) gnu.expr.ExpVisitor.visit(ExpVisitor.java:51) gnu.expr.InlineCalls.visit(InlineCalls.java:46) gnu.expr.InlineCalls.visit(InlineCalls.java:28) gnu.expr.LambdaExp.visitChildrenOnly(LambdaExp.java:1664) gnu.expr.LambdaExp.visitChildren(LambdaExp.java:1651) gnu.expr.InlineCalls.visitScopeExp(InlineCalls.java:279) gnu.expr.InlineCalls.visitLambdaExp(InlineCalls.java:349) gnu.expr.InlineCalls.visitLambdaExp(InlineCalls.java:28) gnu.expr.LambdaExp.visit(LambdaExp.java:1640) gnu.expr.ExpVisitor.visit(ExpVisitor.java:55) gnu.expr.InlineCalls.visit(InlineCalls.java:46) gnu.expr.InlineCalls.visit(InlineCalls.java:28) gnu.expr.ExpVisitor.visitAndUpdate(ExpVisitor.java:161) gnu.expr.ExpVisitor.visitExps(ExpVisitor.java:175) gnu.expr.ApplyExp.visitArgs(ApplyExp.java:415) gnu.kawa.reflect.CompileInvoke.validateApplyInvoke(CompileInvoke.java:23) java.lang.reflect.Method.invoke(Native Method) gnu.expr.InlineCalls.maybeInline(InlineCalls.java:467) gnu.expr.QuoteExp.validateApply(QuoteExp.java:150) gnu.expr.ReferenceExp.validateApply(ReferenceExp.java:191) gnu.kawa.functions.CompilationHelpers.validateApplyToArgs(CompilationHelpers.java:66) java.lang.reflect.Method.invoke(Native Method) gnu.expr.InlineCalls.maybeInline(InlineCalls.java:467) gnu.expr.QuoteExp.validateApply(QuoteExp.java:150) gnu.expr.ReferenceExp.validateApply(ReferenceExp.java:191) gnu.expr.InlineCalls.visitApplyExp(InlineCalls.java:119) gnu.expr.InlineCalls.visitApplyExp(InlineCalls.java:28) gnu.expr.ApplyExp.visit(ApplyExp.java:410) gnu.expr.ExpVisitor.visit(ExpVisitor.java:55) gnu.expr.InlineCalls.visit(InlineCalls.java:46) gnu.expr.QuoteExp.validateApply(QuoteExp.java:162) gnu.expr.ReferenceExp.validateApply(ReferenceExp.java:191) gnu.kawa.functions.CompilationHelpers.validateApplyToArgs(CompilationHelpers.java:66) java.lang.reflect.Method.invoke(Native Method) gnu.expr.InlineCalls.maybeInline(InlineCalls.java:467) gnu.expr.QuoteExp.validateApply(QuoteExp.java:150) gnu.expr.ReferenceExp.validateApply(ReferenceExp.java:191) gnu.expr.InlineCalls.visitApplyExp(InlineCalls.java:119) gnu.expr.InlineCalls.visitApplyExp(InlineCalls.java:28) gnu.expr.ApplyExp.visit(ApplyExp.java:410) gnu.expr.ExpVisitor.visit(ExpVisitor.java:51) gnu.expr.InlineCalls.visit(InlineCalls.java:46) gnu.expr.InlineCalls.visitBeginExp(InlineCalls.java:272) gnu.expr.InlineCalls.visitBeginExp(InlineCalls.java:28) gnu.expr.BeginExp.visit(BeginExp.java:156) gnu.expr.ExpVisitor.visit(ExpVisitor.java:51) gnu.expr.InlineCalls.visit(InlineCalls.java:46) gnu.expr.InlineCalls.visit(InlineCalls.java:28) gnu.expr.LambdaExp.visitChildrenOnly(LambdaExp.java:1664) gnu.expr.LambdaExp.visitChildren(LambdaExp.java:1651) gnu.expr.InlineCalls.visitScopeExp(InlineCalls.java:279) gnu.expr.InlineCalls.visitLambdaExp(InlineCalls.java:349) gnu.expr.InlineCalls.visitLambdaExp(InlineCalls.java:28) gnu.expr.ExpVisitor.visitModuleExp(ExpVisitor.java:103) gnu.expr.ModuleExp.visit(ModuleExp.java:482) gnu.expr.ExpVisitor.visit(ExpVisitor.java:51) gnu.expr.InlineCalls.visit(InlineCalls.java:46) gnu.expr.InlineCalls.inlineCalls(InlineCalls.java:33) gnu.expr.Compilation.walkModule(Compilation.java:994) gnu.expr.Compilation.process(Compilation.java:1965) gnu.expr.ModuleInfo.loadByStages(ModuleInfo.java:330) gnu.expr.ModuleExp.evalModule1(ModuleExp.java:238) gnu.expr.ModuleExp.evalModule(ModuleExp.java:198) gnu.expr.Language.eval(Language.java:943) gnu.expr.Language.eval(Language.java:883) gnu.expr.Language.eval(Language.java:865) com.google.appinventor.components.runtime.util.AppInvHTTPD.serve(AppInvHTTPD.java:197) com.google.appinventor.components.runtime.util.NanoHTTPD$HTTPSession.run(NanoHTTPD.java:489) java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1137) java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:637) java.lang.Thread.run(Thread.java:1012)

[Kevinkun]

After import a new extension, you need to disconnect the companion and reconnect.

And have you tried after compile and install the apk?

[raywong]

yes, I disconnect the companion and reconnect it, and it still doesn't work.
However, I compiled and installed the apk and it works. So it is my computer problem??

[Anke]

Try this one: ext.aia (309.9 KB)

[Anke]

No issues here with USB connection (on a Pixel 4XL, Android 12):

[Taifun]

@raywong

no such class: de.ullisroboterseite.ursai2pahomqtt.UrsPahoMqttClient

See also the explanation here Got this error "java.lang.RuntimeException: no such class" when import extension - #5 by Taifun

Taifun

[raywong]

I tried the aia file, same error message

[raywong]

thanks, I will try to install the mentioned aistarter

[ABG]

I went looking for extension-free MQTT AI2 posts, and found this JavaScript based setup:

MQTT For App Inventor

That site has several more MQTT posts:

Blog Posts

[Anke]

@raywong

I tried the aia file, same error

Try to delete all assets from the Companion app and re-connect with USB.

How to delete all files from assets with Companion

Here is an app that can be used to remove all files from assets with Companion - regardless of the Android version of the test device. This is sometimes necessary so that it still works (properly), for example after an extension update. deleteAssetsCompanion.aia (800.7 KB) Credit to Sunny - @vknow360 for his FileTools extension! [grafik] Android 9: [grafik] After that, disconnect Companion, reload the browser and reconnect to Companion...