I have a Spring Boot application, which is running fine and has with the following setup
Spring Webflux + Tomcat 9 I have a Spring Boot application, which is running fine and has with the following setup - Spring Webflux + Tomcat - Spring Actuator as dependency. - Spring Boot 2.1.2 - Java 1.8.0_212 - Gradle 5.1 to build However when I update to Spring Boot 2.1.7 & Spring 5.1.9 the application fails to start. This is the error in the logs java.lang.IllegalStateException: Calling [asyncOperation()] is not valid for a request with Async state [COMPLETING] This is the stack trace org.apache.coyote.AsyncStateMachine.asyncOperation(AsyncStateMachine.java:269) org.apache.coyote.AbstractProcessor.dispatch(AbstractProcessor.java:203) org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:53) org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:853) org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1587) org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) java.lang.Thread.run(Thread.java:748) What could be the issue here ? However when I update to Spring Boot 2.1.7 & Spring 5.1.9 the application fails to start. This is the error in the logs *java.lang.IllegalStateException: Calling [asyncOperation()] is not valid for a request with Async state [COMPLETING] * This is the stack trace *org.apache.coyote.AsyncStateMachine.asyncOperation(AsyncStateMachine.java:269) org.apache.coyote.AbstractProcessor.dispatch(AbstractProcessor.java:203) org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:53) org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:853) org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1587) org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) java.lang.Thread.run(Thread.java:748)* What could be the issue here ?