[KafkaTrigger] Errors while retrieving function metadata using BindingName in cardinality=Cardinality.MANY mode

Start by tracing the conversion path in DataOperations.apply, DataSource.computeByType, and the RpcCollectionLongDataSource and RpcCollectionStringDataSource classes named in the traces. Reproduce the Kafka trigger with Cardinality.MANY and the OffsetArray and TopicArray bindings. Done means these metadata arrays no longer cause ClassCastException and the existing bindings still resolve correctly.

Kafka trigger function has these metadata: Offset (long), Topic (string), key, partition, timestamp and headers. I was able to retrieve all this data using a basic function:

public class KafkaTriggerJava {
  @FunctionName("KafkaTriggerJava")
  public void run(
      @KafkaTrigger(
              name = "kafkaTrigger",
              topic = "test-topic",
              brokerList = "localhost:9092",
              authenticationMode = BrokerAuthenticationMode.PLAIN,
              protocol = BrokerProtocol.PLAINTEXT,
              consumerGroup = "test-group")
          String kafkaEventData,
      @BindingName("Key") String key,
      @BindingName("Offset") int offset,
      @BindingName("Partition") int partition,
      final ExecutionContext context) {
    context.getLogger().info("Payload: " + kafkaEventData);
  }
}

Then I set cardinality=Cardinality.MANY and tried the following binding names:

           @BindingName("KeyArray") Object[] key,
           @BindingName("OffsetArray") Object[] offset,
           @BindingName("TopicArray") Object[] topic,
           @BindingName("PartitionArray") Object[] partition,
           @BindingName("TimestampArray") Object[] timestamp, 
           @BindingName("HeadersArray") String[] headers

While I was able to get some of the data, "OffsetArray" and "TopicArray" ran into data conversion errors.
Trace for "OffsetArray":

Exception: ClassCastException: class com.microsoft.azure.functions.shaded.com.google.protobuf.LongArrayList cannot be cast to class java.lang.String (com.microsoft.azure.functions.shaded.com.google.protobuf.LongArrayList is in unnamed module of loader 'app'; java.lang.String is in module java.base of loader 'bootstrap')
Stack: java.lang.ClassCastException: class com.microsoft.azure.functions.shaded.com.google.protobuf.LongArrayList cannot be cast to class java.lang.String (com.microsoft.azure.functions.shaded.com.google.protobuf.LongArrayList is in unnamed module of loader 'app'; java.lang.String is in module java.base of loader 'bootstrap')
[2025-10-29T05:03:58.349Z]      at com.microsoft.azure.functions.worker.binding.DataOperations.apply(DataOperations.java:99)
[2025-10-29T05:03:58.352Z]      at com.microsoft.azure.functions.worker.binding.DataSource.computeByType(DataSource.java:56)
[2025-10-29T05:03:58.354Z]      at com.microsoft.azure.functions.worker.binding.RpcCollectionLongDataSource.computeByType(RpcCollectionLongDataSource.java:10)
[2025-10-29T05:03:58.356Z]      at com.microsoft.azure.functions.worker.binding.DataSource.computeByName(DataSource.java:42)
[2025-10-29T05:03:58.359Z]      at com.microsoft.azure.functions.worker.binding.RpcCollectionLongDataSource.computeByName(RpcCollectionLongDataSource.java:10)
[2025-10-29T05:03:58.361Z]      at com.microsoft.azure.functions.worker.binding.BindingDataStore.getTriggerMetatDataByName(BindingDataStore.java:72)
[2025-10-29T05:03:58.363Z]      at com.microsoft.azure.functions.worker.broker.ParameterResolver.resolve(ParameterResolver.java:47)
[2025-10-29T05:03:58.365Z]      at com.microsoft.azure.functions.worker.broker.ParameterResolver.resolveArguments(ParameterResolver.java:22)
[2025-10-29T05:03:58.367Z]      at com.microsoft.azure.functions.worker.broker.EnhancedJavaMethodExecutorImpl.execute(EnhancedJavaMethodExecutorImpl.java:20)
[2025-10-29T05:03:58.370Z]      at com.microsoft.azure.functions.worker.chain.FunctionExecutionMiddleware.invoke(FunctionExecutionMiddleware.java:19)
[2025-10-29T05:03:58.372Z]      at com.microsoft.azure.functions.worker.chain.InvocationChain.doNext(InvocationChain.java:21)
[2025-10-29T05:03:58.374Z]      at com.microsoft.azure.functions.worker.broker.JavaFunctionBroker.invokeMethod(JavaFunctionBroker.java:198)
[2025-10-29T05:03:58.376Z]      at com.microsoft.azure.functions.worker.handler.InvocationRequestHandler.execute(InvocationRequestHandler.java:34)
[2025-10-29T05:03:58.378Z]      at com.microsoft.azure.functions.worker.handler.InvocationRequestHandler.execute(InvocationRequestHandler.java:10)
[2025-10-29T05:03:58.380Z]      at com.microsoft.azure.functions.worker.handler.MessageHandler.handle(MessageHandler.java:44)
[2025-10-29T05:03:58.383Z]      at com.microsoft.azure.functions.worker.JavaWorkerClient$StreamingMessagePeer.lambda$onNext$0(JavaWorkerClient.java:94)
[2025-10-29T05:03:58.385Z]      at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:515)
[2025-10-29T05:03:58.387Z]      at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
[2025-10-29T05:03:58.390Z]      at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
[2025-10-29T05:03:58.392Z]      at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
[2025-10-29T05:03:58.394Z]      at java.base/java.lang.Thread.run(Thread.java:834)

Trace for "TopicArray":

Exception: ClassCastException: class com.microsoft.azure.functions.shaded.com.google.protobuf.LazyStringArrayList cannot be cast to class java.lang.String (com.microsoft.azure.functions.shaded.com.google.protobuf.LazyStringArrayList is in unnamed module of loader 'app'; java.lang.String is in module java.base of loader 'bootstrap')
Stack: java.lang.ClassCastException: class com.microsoft.azure.functions.shaded.com.google.protobuf.LazyStringArrayList cannot be cast to class java.lang.String (com.microsoft.azure.functions.shaded.com.google.protobuf.LazyStringArrayList is in unnamed module of loader 'app'; java.lang.String is in module java.base of loader 'bootstrap')
[2025-10-29T04:43:25.493Z]      at com.microsoft.azure.functions.worker.binding.DataOperations.apply(DataOperations.java:99)
[2025-10-29T04:43:25.495Z]      at com.microsoft.azure.functions.worker.binding.DataSource.computeByType(DataSource.java:56)
[2025-10-29T04:43:25.498Z]      at com.microsoft.azure.functions.worker.binding.RpcCollectionStringDataSource.computeByType(RpcCollectionStringDataSource.java:10)
[2025-10-29T04:43:25.500Z]      at com.microsoft.azure.functions.worker.binding.DataSource.computeByName(DataSource.java:42)
[2025-10-29T04:43:25.503Z]      at com.microsoft.azure.functions.worker.binding.RpcCollectionStringDataSource.computeByName(RpcCollectionStringDataSource.java:10)
[2025-10-29T04:43:25.506Z]      at com.microsoft.azure.functions.worker.binding.BindingDataStore.getTriggerMetatDataByName(BindingDataStore.java:72)
[2025-10-29T04:43:25.509Z]      at com.microsoft.azure.functions.worker.broker.ParameterResolver.resolve(ParameterResolver.java:47)
[2025-10-29T04:43:25.512Z]      at com.microsoft.azure.functions.worker.broker.ParameterResolver.resolveArguments(ParameterResolver.java:22)
[2025-10-29T04:43:25.515Z]      at com.microsoft.azure.functions.worker.broker.EnhancedJavaMethodExecutorImpl.execute(EnhancedJavaMethodExecutorImpl.java:20)
[2025-10-29T04:43:25.518Z]      at com.microsoft.azure.functions.worker.chain.FunctionExecutionMiddleware.invoke(FunctionExecutionMiddleware.java:19)
[2025-10-29T04:43:25.521Z]      at com.microsoft.azure.functions.worker.chain.InvocationChain.doNext(InvocationChain.java:21)
[2025-10-29T04:43:25.525Z]      at com.microsoft.azure.functions.worker.broker.JavaFunctionBroker.invokeMethod(JavaFunctionBroker.java:198)
[2025-10-29T04:43:25.528Z]      at com.microsoft.azure.functions.worker.handler.InvocationRequestHandler.execute(InvocationRequestHandler.java:34)
[2025-10-29T04:43:25.532Z]      at com.microsoft.azure.functions.worker.handler.InvocationRequestHandler.execute(InvocationRequestHandler.java:10)
[2025-10-29T04:43:25.536Z]      at com.microsoft.azure.functions.worker.handler.MessageHandler.handle(MessageHandler.java:44)
[2025-10-29T04:43:25.539Z]      at com.microsoft.azure.functions.worker.JavaWorkerClient$StreamingMessagePeer.lambda$onNext$0(JavaWorkerClient.java:94)
[2025-10-29T04:43:25.543Z]      at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:515)
[2025-10-29T04:43:25.547Z]      at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
[2025-10-29T04:43:25.550Z]      at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
[2025-10-29T04:43:25.553Z]      at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
[2025-10-29T04:43:25.556Z]      at java.base/java.lang.Thread.run(Thread.java:834)