JavaプログラムのClassCastException

前提

PostgreSQLに対するSELECT文の結果を表示するプログラムについて、実行時エラーが発生します。

実現したいこと

エラーを解消し、PostgreSQLに対するSELECT文の結果を表示する。

発生している問題・エラーメッセージ

ClassCastException: class com.microsoft.azure.functions.worker.binding.RpcHttpDataTarget cannot be cast to class com.microsoft.azure.functions.rpc.messages.TypedData$Builder (com.microsoft.azure.functions.worker.binding.RpcHttpDataTarget and com.microsoft.azure.functions.rpc.messages.TypedData$Builder are in unnamed module of loader 'app') Stack: java.lang.ClassCastException: class com.microsoft.azure.functions.worker.binding.RpcHttpDataTarget cannot be cast to class com.microsoft.azure.functions.rpc.messages.TypedData$Builder (com.microsoft.azure.functions.worker.binding.RpcHttpDataTarget and com.microsoft.azure.functions.rpc.messages.TypedData$Builder are in unnamed module of loader 'app') at java.base/java.util.Optional.map(Optional.java:265) at com.microsoft.azure.functions.worker.binding.DataTarget.computeFromValue(DataTarget.java:26) at com.microsoft.azure.functions.worker.binding.BindingDataStore.lambda$getDataTargetTypedValue$1(BindingDataStore.java:113) at java.base/java.util.Optional.map(Optional.java:265) at com.microsoft.azure.functions.worker.binding.BindingDataStore.getDataTargetTypedValue(BindingDataStore.java:111) at com.microsoft.azure.functions.worker.broker.JavaFunctionBroker.invokeMethod(JavaFunctionBroker.java:63) at com.microsoft.azure.functions.worker.handler.InvocationRequestHandler.execute(InvocationRequestHandler.java:37) at com.microsoft.azure.functions.worker.handler.InvocationRequestHandler.execute(InvocationRequestHandler.java:12) at com.microsoft.azure.functions.worker.handler.MessageHandler.handle(MessageHandler.java:45) at com.microsoft.azure.functions.worker.JavaWorkerClient$StreamingMessagePeer.lambda$onNext$0(JavaWorkerClient.java:92) at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:515) at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264) at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128) at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628) at java.base/java.lang.Thread.run(Thread.java:829)

※実行環境がAzure Functionsのため、そちらのメッセージが含まれています。

該当のソースコード

Java
1public class ConfirmQueryResult {
2    public static void main(String[] args) throws Exception{
3
4        (--中略--)
5        OpePostgreSQL opePostgreSQL = new OpePostgreSQL();
6        ResultSet resultSet = opePostgreSQL.readData(connection);
7        System.out.println(resultSet);
8   }
9}

Java
1public class OpePostgreSQL {
2     public ResultSet readData(Connection connection) throws SQLException {
3        PreparedStatement readStatement = connection.prepareStatement("SELECT * FROM table;");
4        ResultSet resultSet = readStatement.executeQuery();
5        if (!resultSet.next()) {
6            return null;
7        }        
8        return resultSet;
9    }
10}