关于org.springframework.lang.Nullable

2019-07-05 17:23:49,626 DEBUG AnnotationAttributesReadingVisitor.visitEnd:51 - Failed to class-load type while reading annotation metadata. This is a non-fatal error, but certain annotation metadata may be unavailable.
java.lang.ClassNotFoundException: org.springframework.lang.Nullable
    at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1308) ~[catalina.jar:8.5.31]
    at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1136) ~[catalina.jar:8.5.31]
    at org.springframework.core.type.classreading.RecursiveAnnotationAttributesVisitor.visitEnd(RecursiveAnnotationAttributesVisitor.java:47) ~[spring-core-4.1.6.RELEASE.jar:4.1.6.RELEASE]
    at org.springframework.asm.ClassReader.readAnnotationValues(ClassReader.java:1802) [spring-core-4.1.6.RELEASE.jar:4.1.6.RELEASE]
    at org.springframework.asm.ClassReader.readMethod(ClassReader.java:976) [spring-core-4.1.6.RELEASE.jar:4.1.6.RELEASE]
    at org.springframework.asm.ClassReader.accept(ClassReader.java:695) [spring-core-4.1.6.RELEASE.jar:4.1.6.RELEASE]
    at org.springframework.asm.ClassReader.accept(ClassReader.java:508) [spring-core-4.1.6.RELEASE.jar:4.1.6.RELEASE]
    at org.springframework.core.type.classreading.SimpleMetadataReader.<init>(SimpleMetadataReader.java:64) [spring-core-4.1.6.RELEASE.jar:4.1.6.RELEASE]
    at org.springframework.core.type.classreading.SimpleMetadataReaderFactory.getMetadataReader(SimpleMetadataReaderFactory.java:98) [spring-core-4.1.6.RELEASE.jar:4.1.6.RELEASE]
    at org.springframework.core.type.classreading.CachingMetadataReaderFactory.getMetadataReader(CachingMetadataReaderFactory.java:102) [spring-core-4.1.6.RELEASE.jar:4.1.6.RELEASE]
    at org.springframework.core.type.classreading.SimpleMetadataReaderFactory.getMetadataReader(SimpleMetadataReaderFactory.java:93) [spring-core-4.1.6.RELEASE.jar:4.1.6.RELEASE]
    at org.springframework.context.annotation.ConfigurationClassUtils.checkConfigurationClassCandidate(ConfigurationClassUtils.java:93) [spring-context-4.1.6.RELEASE.jar:4.1.6.RELEASE]
    at org.springframework.context.annotation.ConfigurationClassPostProcessor.processConfigBeanDefinitions(ConfigurationClassPostProcessor.java:278) [spring-context-4.1.6.RELEASE.jar:4.1.6.RELEASE]
    at org.springframework.context.annotation.ConfigurationClassPostProcessor.postProcessBeanDefinitionRegistry(ConfigurationClassPostProcessor.java:239) [spring-context-4.1.6.RELEASE.jar:4.1.6.RELEASE]
    at org.springframework.context.support.PostProcessorRegistrationDelegate.invokeBeanDefinitionRegistryPostProcessors(PostProcessorRegistrationDelegate.java:254) [spring-context-4.1.6.RELEASE.jar:4.1.6.RELEASE]
    at org.springframework.context.support.PostProcessorRegistrationDelegate.invokeBeanFactoryPostProcessors(PostProcessorRegistrationDelegate.java:94) [spring-context-4.1.6.RELEASE.jar:4.1.6.RELEASE]
    at org.springframework.context.support.AbstractApplicationContext.invokeBeanFactoryPostProcessors(AbstractApplicationContext.java:606) [spring-context-4.1.6.RELEASE.jar:4.1.6.RELEASE]
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:462) [spring-context-4.1.6.RELEASE.jar:4.1.6.RELEASE]
    at org.springframework.web.context.ContextLoader.configureAndRefreshWebApplicationContext(ContextLoader.java:403) [spring-web-4.1.6.RELEASE.jar:4.1.6.RELEASE]
    at org.springframework.web.context.ContextLoader.initWebApplicationContext(ContextLoader.java:306) [spring-web-4.1.6.RELEASE.jar:4.1.6.RELEASE]
    at org.springframework.web.context.ContextLoaderListener.contextInitialized(ContextLoaderListener.java:106) [spring-web-4.1.6.RELEASE.jar:4.1.6.RELEASE]
    at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:4792) [catalina.jar:8.5.31]
    at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5256) [catalina.jar:8.5.31]
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150) [catalina.jar:8.5.31]
    at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:754) [catalina.jar:8.5.31]
    at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:730) [catalina.jar:8.5.31]
    at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:734) [catalina.jar:8.5.31]
    at org.apache.catalina.startup.HostConfig.manageApp(HostConfig.java:1736) [catalina.jar:8.5.31]
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_171]
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_171]
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_171]
    at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_171]
    at org.apache.tomcat.util.modeler.BaseModelMBean.invoke(BaseModelMBean.java:300) [tomcat-coyote.jar:8.5.31]
    at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.invoke(DefaultMBeanServerInterceptor.java:819) [na:1.8.0_171]
    at com.sun.jmx.mbeanserver.JmxMBeanServer.invoke(JmxMBeanServer.java:801) [na:1.8.0_171]
    at org.apache.catalina.mbeans.MBeanFactory.createStandardContext(MBeanFactory.java:482) [catalina.jar:8.5.31]
    at org.apache.catalina.mbeans.MBeanFactory.createStandardContext(MBeanFactory.java:431) [catalina.jar:8.5.31]
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_171]
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_171]
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_171]
    at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_171]
    at org.apache.tomcat.util.modeler.BaseModelMBean.invoke(BaseModelMBean.java:300) [tomcat-coyote.jar:8.5.31]
    at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.invoke(DefaultMBeanServerInterceptor.java:819) [na:1.8.0_171]
    at com.sun.jmx.mbeanserver.JmxMBeanServer.invoke(JmxMBeanServer.java:801) [na:1.8.0_171]
    at javax.management.remote.rmi.RMIConnectionImpl.doOperation(RMIConnectionImpl.java:1468) [na:1.8.0_171]
    at javax.management.remote.rmi.RMIConnectionImpl.access$300(RMIConnectionImpl.java:76) [na:1.8.0_171]
    at javax.management.remote.rmi.RMIConnectionImpl$PrivilegedOperation.run(RMIConnectionImpl.java:1309) [na:1.8.0_171]
    at javax.management.remote.rmi.RMIConnectionImpl.doPrivilegedOperation(RMIConnectionImpl.java:1401) [na:1.8.0_171]
    at javax.management.remote.rmi.RMIConnectionImpl.invoke(RMIConnectionImpl.java:829) [na:1.8.0_171]
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_171]
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_171]
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_171]
    at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_171]
    at sun.rmi.server.UnicastServerRef.dispatch(UnicastServerRef.java:357) [na:1.8.0_171]
    at sun.rmi.transport.Transport$1.run(Transport.java:200) [na:1.8.0_171]
    at sun.rmi.transport.Transport$1.run(Transport.java:197) [na:1.8.0_171]
    at java.security.AccessController.doPrivileged(Native Method) [na:1.8.0_171]
    at sun.rmi.transport.Transport.serviceCall(Transport.java:196) [na:1.8.0_171]
    at sun.rmi.transport.tcp.TCPTransport.handleMessages(TCPTransport.java:573) [na:1.8.0_171]
    at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run0(TCPTransport.java:835) [na:1.8.0_171]
    at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.lambda$run$0(TCPTransport.java:688) [na:1.8.0_171]
    at java.security.AccessController.doPrivileged(Native Method) [na:1.8.0_171]
    at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run(TCPTransport.java:687) [na:1.8.0_171]
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) ~[na:1.8.0_171]
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) ~[na:1.8.0_171]
    at java.lang.Thread.run(Thread.java:748) ~[na:1.8.0_171]

spring mvc项目需要操作redis ,  使用maven 添加如下jar包

<dependency>
            <groupId>org.springframework.data</groupId>
            <artifactId>spring-data-redis</artifactId>
            <version>1.7.1.RELEASE</version>
       </dependency>
        <dependency>
            <groupId>redis.clients</groupId>
            <artifactId>jedis</artifactId>
            <version>2.9.0</version>
        </dependency>

启动报上面的错误。

百度查了一下，大多是说spring-data-redis 的版本问题，换成1.6.2 的确不再报错。

但是网上说1.7以后支持redis 集群，虽然我现在不需要，但是还是要预留的，问题还是要解决。不能逃避。

根据错误提示项目中的确找不到org.springframework.lang.Nullable 这个类。我的代码也没有用到，那应该是

某个jar用到了。最后找到是

<dependency>
            <groupId>org.springframework.amqp</groupId>
            <artifactId>spring-rabbit</artifactId>
            <version>2.1.2.RELEASE</version>
        </dependency>

这个jar有用到Nullable(该类是spring5 以后出现的)。解决方法是换低版本。

现在问题是为什么在我引入spring-data-redis之前并没有报出该错误，报错代码：

 RecursiveAnnotationAttributesVisitor类，
public final void visitEnd() {
        try {
            Class<?> annotationClass = this.classLoader.loadClass(this.annotationType);
            this.doVisitEnd(annotationClass);
        } catch (ClassNotFoundException var2) {
            this.logger.debug("Failed to class-load type while reading annotation metadata. This is a non-fatal error, but certain annotation metadata may be unavailable.", var2);
        }

    }

猜测是logger.dubug 这个 logger 的日志级别不一致，调试发现this.logger.isDebuged = true;

我把spring-data-redis 换成1.6.2 ，调试发现this.logger.isDebuged() =  false

如上验证了我的猜想，logger 的日志级别不一样。

但是为什么不同版本，连logger 实例的类型都不一样了。。（而且SLF4JLocationAwareLog 这个竟然又是hibernate-validate 引入的jboss-logging中的类）。

越看越乱。

临时解决方案(有知道解决方法的请留意)：

方案一、 spring-data-redis 换成1.6.2

二、logback 中 

<logger name="org.springframework" level="INFO"></logger> (因为spring 报出的debug，忽略了)。

三、

<dependency>
            <groupId>org.springframework.data</groupId>
            <artifactId>spring-data-redis</artifactId>
            <version>1.7.1.RELEASE</version>
            <exclusions>
                <exclusion>
                    <artifactId>jcl-over-slf4j</artifactId>
                    <groupId>org.slf4j</groupId>
                </exclusion>
            </exclusions>
        </dependency>
去掉jcl-over-slf4j.