java.lang.reflect.InaccessibleObjectException: Unable to make field private final while submitting task to executor service after JDK 17 upgrade

Question

We upgraded our application to springboot 3.1.4 from springboot 2.5.4 and JDK from 1.8 to 17. We get the java.lang.reflect.InaccessibleObjectException: Unable to make field private final java.util.concurrent.ExecutorService when we submit a callable task to the Executor service.

The code is as below

@Component
public class ThreadPoolInitializer {
private static ExecutorService parallelExecutor = null;
private static ExecutorService sequenceExecutor = null;

private static final int DEFAULT_THREAD_POOL_SIZE = 50;

public void setupExecutor() {
    parallelExecutor = Executors.newFixedThreadPool(DEFAULT_THREAD_POOL_SIZE);
    sequenceExecutor = Executors.newSingleThreadExecutor();
}

public ExecutorService getParallelExecutor() {
    return parallelExecutor;
}

public ExecutorService getSequenceExecutor() {
    return sequenceExecutor;
}
}

we are calling this sequenceExecutor from another method and submitting the task.

@Autowired
private ThreadPoolInitializer execPool;

public void addTasktoPool(CnfConfigPushTask task) {
    VesEventRoot event = task.getEvent();
        try {
            TaskHandler taskHandler = (TaskHandler) ctx.getBean(event.getType().toString());
            if (taskHandler != null) {
                taskHandler.setTask(task);
            } else {
                log.warn("No Task Handler for task : " + event.getType() + task);
            }
            task.setRetryCount(4);
            execPool.getSequenceExecutor().submit((Callable<String>) taskHandler);
        } catch (Exception e) {
            log.error("Exception while updating task : " +  task, e);
        }
    
}

We are seeing the exception here execPool.getSequenceExecutor().submit((Callable<String>) taskHandler);

the exception is as below

java.lang.reflect.InaccessibleObjectException: Unable to make field private final java.util.concurrent.ExecutorService java.util.concurrent.Executors$DelegatedExecutorService.e accessible: module java.base does not "opens java.util.concurrent" to unnamed module @327471b5
at java.lang.reflect.AccessibleObject.checkCanSetAccessible(AccessibleObject.java:354) ~[?:?]
at java.lang.reflect.AccessibleObject.checkCanSetAccessible(AccessibleObject.java:297) ~[?:?]
at java.lang.reflect.Field.checkCanSetAccessible(Field.java:178) ~[?:?]
at java.lang.reflect.AccessibleObject.setAccessible(AccessibleObject.java:130) ~[?:?]
at org.apache.commons.lang.builder.ReflectionToStringBuilder.appendFieldsIn(ReflectionToStringBuilder.java:597) ~[commons-lang-2.6.jar!/:2.6]
at org.apache.commons.lang.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:768) ~[commons-lang-2.6.jar!/:2.6]
at org.apache.commons.lang.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:287) ~[commons-lang-2.6.jar!/:2.6]
at org.apache.commons.lang.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:121) ~[commons-lang-2.6.jar!/:2.6]
at com.mavenir.cms.vnf.util.LoggingAspect.getValue(LoggingAspect.java:107) ~[classes!/:0.0.1]
at com.mavenir.cms.vnf.util.LoggingAspect.logAfterReturning(LoggingAspect.java:65) ~[classes!/:0.0.1]
at jdk.internal.reflect.GeneratedMethodAccessor46.invoke(Unknown Source) ~[?:?]
at jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[?:?]
at java.lang.reflect.Method.invoke(Method.java:568) ~[?:?]
at org.springframework.aop.aspectj.AbstractAspectJAdvice.invokeAdviceMethodWithGivenArgs(AbstractAspectJAdvice.java:637) ~[spring-aop-6.0.12.jar!/:6.0.12]
at org.springframework.aop.aspectj.AbstractAspectJAdvice.invokeAdviceMethod(AbstractAspectJAdvice.java:620) ~[spring-aop-6.0.12.jar!/:6.0.12]
at org.springframework.aop.aspectj.AspectJAfterReturningAdvice.afterReturning(AspectJAfterReturningAdvice.java:66) ~[spring-aop-6.0.12.jar!/:6.0.12]
at org.springframework.aop.framework.adapter.AfterReturningAdviceInterceptor.invoke(AfterReturningAdviceInterceptor.java:58) ~[spring-aop-6.0.12.jar!/:6.0.12]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:173) ~[spring-aop-6.0.12.jar!/:6.0.12]
at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:751) ~[spring-aop-6.0.12.jar!/:6.0.12]
at org.springframework.aop.aspectj.MethodInvocationProceedingJoinPoint.proceed(MethodInvocationProceedingJoinPoint.java:89) ~[spring-aop-6.0.12.jar!/:6.0.12]
at com.mavenir.cms.vnf.util.LoggingAspect.logAround(LoggingAspect.java:52) ~[classes!/:0.0.1]
at jdk.internal.reflect.GeneratedMethodAccessor42.invoke(Unknown Source) ~[?:?]
at jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[?:?]
at java.lang.reflect.Method.invoke(Method.java:568) ~[?:?]
at org.springframework.aop.aspectj.AbstractAspectJAdvice.invokeAdviceMethodWithGivenArgs(AbstractAspectJAdvice.java:637) ~[spring-aop-6.0.12.jar!/:6.0.12]
at org.springframework.aop.aspectj.AbstractAspectJAdvice.invokeAdviceMethod(AbstractAspectJAdvice.java:627) ~[spring-aop-6.0.12.jar!/:6.0.12]
at org.springframework.aop.aspectj.AspectJAroundAdvice.invoke(AspectJAroundAdvice.java:71) ~[spring-aop-6.0.12.jar!/:6.0.12]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:173) ~[spring-aop-6.0.12.jar!/:6.0.12]
at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:751) ~[spring-aop-6.0.12.jar!/:6.0.12]
at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:97) ~[spring-aop-6.0.12.jar!/:6.0.12]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:184) ~[spring-aop-6.0.12.jar!/:6.0.12]
at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:751) ~[spring-aop-6.0.12.jar!/:6.0.12]
at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:703) ~[spring-aop-6.0.12.jar!/:6.0.12]
at com.mavenir.cms.ThreadPoolInitializer$$SpringCGLIB$$0.getSequenceExecutor(<generated>) ~[classes!/:0.0.1]
at com.mavenir.cms.cnf.task.CnfConfigPushTaskManager.addTasktoPool(CnfConfigPushTaskManager.java:66) ~[classes!/:0.0.1]
at com.mavenir.cms.cnf.task.CnfConfigPushTaskManager.populateCnfConfigPushTask(CnfConfigPushTaskManager.java:53) ~[classes!/:0.0.1]
at jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:?]
at jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:77) ~[?:?]
at jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[?:?]
at java.lang.reflect.Method.invoke(Method.java:568) ~[?:?]
at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:343) ~[spring-aop-6.0.12.jar!/:6.0.12]
at org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:196) ~[spring-aop-6.0.12.jar!/:6.0.12]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:163) ~[spring-aop-6.0.12.jar!/:6.0.12]
at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:751) ~[spring-aop-6.0.12.jar!/:6.0.12]
at org.springframework.aop.aspectj.AspectJAfterThrowingAdvice.invoke(AspectJAfterThrowingAdvice.java:64) ~[spring-aop-6.0.12.jar!/:6.0.12]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:173) ~[spring-aop-6.0.12.jar!/:6.0.12]
at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:751) ~[spring-aop-6.0.12.jar!/:6.0.12]
at org.springframework.aop.framework.adapter.AfterReturningAdviceInterceptor.invoke(AfterReturningAdviceInterceptor.java:57) ~[spring-aop-6.0.12.jar!/:6.0.12]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:173) ~[spring-aop-6.0.12.jar!/:6.0.12]
at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:751) ~[spring-aop-6.0.12.jar!/:6.0.12]
at org.springframework.aop.aspectj.MethodInvocationProceedingJoinPoint.proceed(MethodInvocationProceedingJoinPoint.java:89) ~[spring-aop-6.0.12.jar!/:6.0.12]
at com.mavenir.cms.vnf.util.LoggingAspect.logAround(LoggingAspect.java:52) ~[classes!/:0.0.1]
at jdk.internal.reflect.GeneratedMethodAccessor42.invoke(Unknown Source) ~[?:?]
at jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[?:?]
at java.lang.reflect.Method.invoke(Method.java:568) ~[?:?]

So we instantiated a singleThreadExecutor and used it and the exception is gone.

Working code:

private ExecutorService singleThreadExecutor =Executors.newSingleThreadExecutor();

public void addTasktoPool(CnfConfigPushTask task) {
    VesEventRoot event = task.getEvent();
        try {
            TaskHandler taskHandler = (TaskHandler) ctx.getBean(event.getType().toString());
            if (taskHandler != null) {
                taskHandler.setTask(task);
            } else {
                log.warn("No Task Handler for task : " + event.getType() + task);
            }
            task.setRetryCount(4);
            singleThreadExecutor.submit((Callable<String>) taskHandler);
        } catch (Exception e) {
            log.error("Exception while updating task : " +  task, e);
        }
    
}

Could not understand why the old code is not working in JDK 17. Please help.