Could not generate CGLIB subclass of class io.lettuce.core.support.ConnectionPoolSupport$1

[peerit12]

Bug Report

Current Behavior

I am current using lettuce for the redis cache implementation.

Input Code

Tried to use connection pooling support for redis connection

but got this exception

Unable to register MBean [clusterConnection] with key 'clusterConnection'; nested exception is org.springframework.aop.framework.AopConfigException: Could not generate CGLIB subclass of class io.lettuce.core.support.ConnectionPoolSupport$1: Common causes of this problem include using a final class or a non-visible class; nested exception is org.springframework.cglib.core.CodeGenerationException: java.lang.reflect.InvocationTargetException-->null

GenericObjectPool<StatefulRedisClusterConnection<String, Object>> pool = ConnectionPoolSupport
.createGenericObjectPool(()->clusterClient.connect(new SerializedObjectCodec()),genericPollConfig );

I was using this code for creating connection poll.

Please suggest some solution

[mp911de]

What are you trying to achieve and why do you want to subclass an anonymous inner class?

[peerit12]

I am trying to create connection pool for redis connection.For creating connection pool I am using ConnectionPoolSupport of lettuce-core

I want my GenericObjectPool to store pool of
StatefulRedisClusterConnection<String, Object>

want to get StatefulRedisClusterConnection Object from this pool.

ERROR  org.springframework.boot.SpringApplication.reportFailure - Application run failed
org.springframework.jmx.export.UnableToRegisterMBeanException: Unable to register MBean [clusterConnection] with key 'clusterConnection'; nested exception is org.springframework.aop.framework.AopConfigException: Could not generate CGLIB subclass of class io.lettuce.core.support.ConnectionPoolSupport$1: Common causes of this problem include using a final class or a non-visible class; nested exception is org.springframework.cglib.core.CodeGenerationException: java.lang.reflect.InvocationTargetException-->null
	at org.springframework.jmx.export.MBeanExporter.registerBeanNameOrInstance(MBeanExporter.java:625) ~[spring-context-5.0.7.RELEASE.jar!/:5.0.7.RELEASE]
	at org.springframework.jmx.export.MBeanExporter.lambda$registerBeans$2(MBeanExporter.java:551) ~[spring-context-5.0.7.RELEASE.jar!/:5.0.7.RELEASE]
	at org.springframework.jmx.export.MBeanExporter$$Lambda$934/663716901.accept(Unknown Source) ~[na:na]
	at java.util.HashMap.forEach(HashMap.java:1280) ~[na:1.8.0_45]
	at org.springframework.jmx.export.MBeanExporter.registerBeans(MBeanExporter.java:551) ~[spring-context-5.0.7.RELEASE.jar!/:5.0.7.RELEASE]
	at org.springframework.jmx.export.MBeanExporter.afterSingletonsInstantiated(MBeanExporter.java:434) ~[spring-context-5.0.7.RELEASE.jar!/:5.0.7.RELEASE]
	at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:777) ~[spring-beans-5.0.7.RELEASE.jar!/:5.0.7.RELEASE]
	at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:869) ~[spring-context-5.0.7.RELEASE.jar!/:5.0.7.RELEASE]
	at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:550) ~[spring-context-5.0.7.RELEASE.jar!/:5.0.7.RELEASE]
	at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:140) ~[spring-boot-2.0.3.RELEASE.jar!/:2.0.3.RELEASE]
	at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:759) [spring-boot-2.0.3.RELEASE.jar!/:2.0.3.RELEASE]
	at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:395) [spring-boot-2.0.3.RELEASE.jar!/:2.0.3.RELEASE]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:327) [spring-boot-2.0.3.RELEASE.jar!/:2.0.3.RELEASE]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1255) [spring-boot-2.0.3.RELEASE.jar!/:2.0.3.RELEASE]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1243) [spring-boot-2.0.3.RELEASE.jar!/:2.0.3.RELEASE]
	at com.franconnect.multitenant.SkyTenantsConfigApplication.main(SkyTenantsConfigApplication.java:55) [classes!/:na]
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_45]
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_45]
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_45]
	at java.lang.reflect.Method.invoke(Method.java:497) ~[na:1.8.0_45]
	at org.springframework.boot.loader.MainMethodRunner.run(MainMethodRunner.java:48) [fcsky-common-multitenant-config-0.0.1.jar:na]
	at org.springframework.boot.loader.Launcher.launch(Launcher.java:87) [fcsky-common-multitenant-config-0.0.1.jar:na]
	at org.springframework.boot.loader.Launcher.launch(Launcher.java:50) [fcsky-common-multitenant-config-0.0.1.jar:na]
	at org.springframework.boot.loader.JarLauncher.main(JarLauncher.java:51) [fcsky-common-multitenant-config-0.0.1.jar:na]
Caused by: org.springframework.aop.framework.AopConfigException: Could not generate CGLIB subclass of class io.lettuce.core.support.ConnectionPoolSupport$1: Common causes of this problem include using a final class or a non-visible class; nested exception is org.springframework.cglib.core.CodeGenerationException: java.lang.reflect.InvocationTargetException-->null
	at org.springframework.aop.framework.CglibAopProxy.getProxy(CglibAopProxy.java:208) ~[spring-aop-5.0.7.RELEASE.jar!/:5.0.7.RELEASE]
	at org.springframework.aop.framework.ProxyFactory.getProxy(ProxyFactory.java:110) ~[spring-aop-5.0.7.RELEASE.jar!/:5.0.7.RELEASE]
	at org.springframework.jmx.export.MBeanExporter.registerLazyInit(MBeanExporter.java:708) ~[spring-context-5.0.7.RELEASE.jar!/:5.0.7.RELEASE]
	at org.springframework.jmx.export.MBeanExporter.registerBeanNameOrInstance(MBeanExporter.java:596) ~[spring-context-5.0.7.RELEASE.jar!/:5.0.7.RELEASE]
	... 23 common frames omitted
Caused by: org.springframework.cglib.core.CodeGenerationException: java.lang.reflect.InvocationTargetException-->null
	at org.springframework.cglib.core.AbstractClassGenerator.generate(AbstractClassGenerator.java:345) ~[spring-core-5.0.7.RELEASE.jar!/:5.0.7.RELEASE]
	at org.springframework.cglib.proxy.Enhancer.generate(Enhancer.java:492) ~[spring-core-5.0.7.RELEASE.jar!/:5.0.7.RELEASE]
	at org.springframework.cglib.core.AbstractClassGenerator$ClassLoaderData$3.apply(AbstractClassGenerator.java:93) ~[spring-core-5.0.7.RELEASE.jar!/:5.0.7.RELEASE]
	at org.springframework.cglib.core.AbstractClassGenerator$ClassLoaderData$3.apply(AbstractClassGenerator.java:91) ~[spring-core-5.0.7.RELEASE.jar!/:5.0.7.RELEASE]
	at org.springframework.cglib.core.internal.LoadingCache$2.call(LoadingCache.java:54) ~[spring-core-5.0.7.RELEASE.jar!/:5.0.7.RELEASE]
	at java.util.concurrent.FutureTask.run(FutureTask.java:266) ~[na:1.8.0_45]
	at org.springframework.cglib.core.internal.LoadingCache.createEntry(LoadingCache.java:61) ~[spring-core-5.0.7.RELEASE.jar!/:5.0.7.RELEASE]
	at org.springframework.cglib.core.internal.LoadingCache.get(LoadingCache.java:34) ~[spring-core-5.0.7.RELEASE.jar!/:5.0.7.RELEASE]
	at org.springframework.cglib.core.AbstractClassGenerator$ClassLoaderData.get(AbstractClassGenerator.java:116) ~[spring-core-5.0.7.RELEASE.jar!/:5.0.7.RELEASE]
	at org.springframework.cglib.core.AbstractClassGenerator.create(AbstractClassGenerator.java:291) ~[spring-core-5.0.7.RELEASE.jar!/:5.0.7.RELEASE]
	at org.springframework.cglib.proxy.Enhancer.createHelper(Enhancer.java:480) ~[spring-core-5.0.7.RELEASE.jar!/:5.0.7.RELEASE]
	at org.springframework.cglib.proxy.Enhancer.createClass(Enhancer.java:337) ~[spring-core-5.0.7.RELEASE.jar!/:5.0.7.RELEASE]
	at org.springframework.aop.framework.ObjenesisCglibAopProxy.createProxyClassAndInstance(ObjenesisCglibAopProxy.java:58) ~[spring-aop-5.0.7.RELEASE.jar!/:5.0.7.RELEASE]
	at org.springframework.aop.framework.CglibAopProxy.getProxy(CglibAopProxy.java:205) ~[spring-aop-5.0.7.RELEASE.jar!/:5.0.7.RELEASE]
	... 26 common frames omitted
Caused by: java.lang.reflect.InvocationTargetException: null
	at sun.reflect.GeneratedMethodAccessor53.invoke(Unknown Source) ~[na:na]
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_45]
	at java.lang.reflect.Method.invoke(Method.java:497) ~[na:1.8.0_45]
	at org.springframework.cglib.core.ReflectUtils.defineClass(ReflectUtils.java:459) ~[spring-core-5.0.7.RELEASE.jar!/:5.0.7.RELEASE]
	at org.springframework.cglib.core.AbstractClassGenerator.generate(AbstractClassGenerator.java:336) ~[spring-core-5.0.7.RELEASE.jar!/:5.0.7.RELEASE]
	... 39 common frames omitted
Caused by: java.lang.VerifyError: Cannot inherit from final class
	at java.lang.ClassLoader.defineClass1(Native Method) ~[na:1.8.0_45]
	at java.lang.ClassLoader.defineClass(ClassLoader.java:760) ~[na:1.8.0_45]
	... 44 common frames omitted

[mp911de]

I'm not sure we can do something about this issue here. Care to post your boot config? Currently, we cannot see why Spring is trying to create a proxy around ConnectionPoolSupport$1

ConnectionPoolSupport$1 is not defined final, according to

RedisClient client = RedisClient.create();

GenericObjectPool<StatefulRedisConnection<String, String>> pool = ConnectionPoolSupport
		.createGenericObjectPool(client::connect, new GenericObjectPoolConfig());

System.out.println(Modifier.isFinal(pool.getClass().getModifiers()));

[peerit12]

So how do i proceed further please suggest any solution.
I am currently using SpringBoot springBootVersion = '2.0.3.RELEASE'
if any other information you need then please let me know

[mp911de]

Please provide a project that is able to reproduce the issue (Ideally using start.spring.io). Currently, we cannot see why Spring is trying to create a proxy around ConnectionPoolSupport$1?

[peerit12]

redis-sample.zip

I have uploaded my project . please use redis host in application.properties
when you try to run this application then shows the same error

[mp911de]

Thanks a lot. Proxying happens because RedisCacheFactory is marked as @Lazy. Moving @Bean methods into a different type removes the necessity for proxying. The pool itself isn't required to be lazy. You can control this aspect with minIdle on the pool.

Proxying GenericObjectPool isn't the best idea as you run into two consequences:

• Enabling JMX will expose the proxy and the actual pool instance as JMX beans. The latter is fine, the former is an artifact of proxying.
• Some methods in GenericObjectPool are final and will produce a huge number of warnings in your log.

[mp911de]

Closing this one as we cannot do anything further here.