我是Spring新手，我正在尝试在Spring Tool Suite中完成this教程的略微修改版本。我遇到了一些我不理解的错误。
这是输出到控制台的一系列错误消息：
SEVERE: StandardWrapper.Throwable
java.lang.IncompatibleClassChangeError: class org.springframework.core.type.classreading.ClassMetadataReadingVisitor has interface org.springframework.asm.ClassVisitor as super class
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(Unknown Source)
at java.security.SecureClassLoader.defineClass(Unknown Source)
at org.apache.catalina.loader.WebappClassLoader.findClassInternal(WebappClassLoader.java:2918)
at org.apache.catalina.loader.WebappClassLoader.findClass(WebappClassLoader.java:1174)
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1669)
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1547)
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(Unknown Source)
at java.security.SecureClassLoader.defineClass(Unknown Source)
at org.apache.catalina.loader.WebappClassLoader.findClassInternal(WebappClassLoader.java:2918)
at org.apache.catalina.loader.WebappClassLoader.findClass(WebappClassLoader.java:1174)
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1669)
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1547)
at org.springframework.core.type.classreading.SimpleMetadataReader.<init>(SimpleMetadataReader.java:63)
at org.springframework.core.type.classreading.SimpleMetadataReaderFactory.getMetadataReader(SimpleMetadataReaderFactory.java:82)
at org.springframework.core.type.classreading.CachingMetadataReaderFactory.getMetadataReader(CachingMetadataReaderFactory.java:102)
at org.springframework.core.type.classreading.SimpleMetadataReaderFactory.getMetadataReader(SimpleMetadataReaderFactory.java:77)
at org.springframework.context.annotation.ConfigurationClassUtils.checkConfigurationClassCandidate(ConfigurationClassUtils.java:70)
at org.springframework.context.annotation.ConfigurationClassPostProcessor.processConfigBeanDefinitions(ConfigurationClassPostProcessor.java:233)
at org.springframework.context.annotation.ConfigurationClassPostProcessor.postProcessBeanDefinitionRegistry(ConfigurationClassPostProcessor.java:203)
at org.springframework.context.support.AbstractApplicationContext.invokeBeanFactoryPostProcessors(AbstractApplicationContext.java:617)
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:446)
at org.springframework.web.servlet.FrameworkServlet.configureAndRefreshWebApplicationContext(FrameworkServlet.java:631)
at org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:588)
at org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:645)
at org.springframework.web.servlet.FrameworkServlet.initWebApplicationContext(FrameworkServlet.java:508)
at org.springframework.web.servlet.FrameworkServlet.initServletBean(FrameworkServlet.java:449)
at org.springframework.web.servlet.HttpServletBean.init(HttpServletBean.java:133)
at javax.servlet.GenericServlet.init(GenericServlet.java:160)
at org.apache.catalina.core.StandardWrapper.initServlet(StandardWrapper.java:1280)
at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1193)
at org.apache.catalina.core.StandardWrapper.load(StandardWrapper.java:1088)
at org.apache.catalina.core.StandardContext.loadOnStartup(StandardContext.java:5176)
at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5460)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1559)
at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1549)
at java.util.concurrent.FutureTask.run(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
Aug 19, 2014 10:14:39 AM org.apache.catalina.core.StandardContext loadOnStartup
SEVERE: Servlet /iSignout threw load() exception
java.lang.IncompatibleClassChangeError: class org.springframework.core.type.classreading.ClassMetadataReadingVisitor has interface org.springframework.asm.ClassVisitor as super class
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(Unknown Source)
at java.security.SecureClassLoader.defineClass(Unknown Source)
at org.apache.catalina.loader.WebappClassLoader.findClassInternal(WebappClassLoader.java:2918)
at org.apache.catalina.loader.WebappClassLoader.findClass(WebappClassLoader.java:1174)
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1669)
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1547)
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(Unknown Source)
at java.security.SecureClassLoader.defineClass(Unknown Source)
at org.apache.catalina.loader.WebappClassLoader.findClassInternal(WebappClassLoader.java:2918)
at org.apache.catalina.loader.WebappClassLoader.findClass(WebappClassLoader.java:1174)
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1669)
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1547)
at org.springframework.core.type.classreading.SimpleMetadataReader.<init>(SimpleMetadataReader.java:63)
at org.springframework.core.type.classreading.SimpleMetadataReaderFactory.getMetadataReader(SimpleMetadataReaderFactory.java:82)
at org.springframework.core.type.classreading.CachingMetadataReaderFactory.getMetadataReader(CachingMetadataReaderFactory.java:102)
at org.springframework.core.type.classreading.SimpleMetadataReaderFactory.getMetadataReader(SimpleMetadataReaderFactory.java:77)
at org.springframework.context.annotation.ConfigurationClassUtils.checkConfigurationClassCandidate(ConfigurationClassUtils.java:70)
at org.springframework.context.annotation.ConfigurationClassPostProcessor.processConfigBeanDefinitions(ConfigurationClassPostProcessor.java:233)
at org.springframework.context.annotation.ConfigurationClassPostProcessor.postProcessBeanDefinitionRegistry(ConfigurationClassPostProcessor.java:203)
at org.springframework.context.support.AbstractApplicationContext.invokeBeanFactoryPostProcessors(AbstractApplicationContext.java:617)
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:446)
at org.springframework.web.servlet.FrameworkServlet.configureAndRefreshWebApplicationContext(FrameworkServlet.java:631)
at org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:588)
at org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:645)
at org.springframework.web.servlet.FrameworkServlet.initWebApplicationContext(FrameworkServlet.java:508)
at org.springframework.web.servlet.FrameworkServlet.initServletBean(FrameworkServlet.java:449)
at org.springframework.web.servlet.HttpServletBean.init(HttpServletBean.java:133)
at javax.servlet.GenericServlet.init(GenericServlet.java:160)
at org.apache.catalina.core.StandardWrapper.initServlet(StandardWrapper.java:1280)
at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1193)
at org.apache.catalina.core.StandardWrapper.load(StandardWrapper.java:1088)
at org.apache.catalina.core.StandardContext.loadOnStartup(StandardContext.java:5176)
at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5460)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1559)
at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1549)
at java.util.concurrent.FutureTask.run(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
Aug 19, 2014 10:14:39 AM org.apache.coyote.AbstractProtocol start
INFO: Starting ProtocolHandler ["http-bio-8080"]
Aug 19, 2014 10:14:39 AM org.apache.coyote.AbstractProtocol start
INFO: Starting ProtocolHandler ["ajp-bio-8009"]
Aug 19, 2014 10:14:39 AM org.apache.catalina.startup.Catalina start
INFO: Server startup in 14222 ms
Aug 19, 2014 10:14:51 AM org.apache.catalina.core.ApplicationContext log
INFO: Initializing Spring FrameworkServlet 'spring'
INFO : org.springframework.web.servlet.DispatcherServlet - FrameworkServlet 'spring': initialization started
INFO : org.springframework.web.context.support.XmlWebApplicationContext - Refreshing WebApplicationContext for namespace 'spring-servlet': startup date [Tue Aug 19 10:14:51 EDT 2014]; root of context hierarchy
INFO : org.springframework.beans.factory.xml.XmlBeanDefinitionReader - Loading XML bean definitions from ServletContext resource [/WEB-INF/spring-servlet.xml]
INFO : org.springframework.context.annotation.ClassPathBeanDefinitionScanner - JSR-250 'javax.annotation.ManagedBean' found and supported for component scanning
INFO : org.springframework.context.annotation.ClassPathBeanDefinitionScanner - JSR-330 'javax.inject.Named' annotation found and supported for component scanning
Aug 19, 2014 10:14:51 AM org.apache.catalina.core.ApplicationContext log
SEVERE: StandardWrapper.Throwable
java.lang.IncompatibleClassChangeError: org/springframework/core/type/classreading/AnnotationMetadataReadingVisitor
at org.springframework.core.type.classreading.SimpleMetadataReader.<init>(SimpleMetadataReader.java:63)
at org.springframework.core.type.classreading.SimpleMetadataReaderFactory.getMetadataReader(SimpleMetadataReaderFactory.java:82)
at org.springframework.core.type.classreading.CachingMetadataReaderFactory.getMetadataReader(CachingMetadataReaderFactory.java:102)
at org.springframework.core.type.classreading.SimpleMetadataReaderFactory.getMetadataReader(SimpleMetadataReaderFactory.java:77)
at org.springframework.context.annotation.ConfigurationClassUtils.checkConfigurationClassCandidate(ConfigurationClassUtils.java:70)
at org.springframework.context.annotation.ConfigurationClassPostProcessor.processConfigBeanDefinitions(ConfigurationClassPostProcessor.java:233)
at org.springframework.context.annotation.ConfigurationClassPostProcessor.postProcessBeanDefinitionRegistry(ConfigurationClassPostProcessor.java:203)
at org.springframework.context.support.AbstractApplicationContext.invokeBeanFactoryPostProcessors(AbstractApplicationContext.java:617)
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:446)
at org.springframework.web.servlet.FrameworkServlet.configureAndRefreshWebApplicationContext(FrameworkServlet.java:631)
at org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:588)
at org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:645)
at org.springframework.web.servlet.FrameworkServlet.initWebApplicationContext(FrameworkServlet.java:508)
at org.springframework.web.servlet.FrameworkServlet.initServletBean(FrameworkServlet.java:449)
at org.springframework.web.servlet.HttpServletBean.init(HttpServletBean.java:133)
at javax.servlet.GenericServlet.init(GenericServlet.java:160)
at org.apache.catalina.core.StandardWrapper.initServlet(StandardWrapper.java:1280)
at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1193)
at org.apache.catalina.core.StandardWrapper.allocate(StandardWrapper.java:865)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:136)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:123)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:100)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:953)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1041)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:603)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:312)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
Aug 19, 2014 10:14:51 AM org.apache.catalina.core.StandardWrapperValve invoke
SEVERE: Allocate exception for servlet spring
java.lang.IncompatibleClassChangeError: org/springframework/core/type/classreading/AnnotationMetadataReadingVisitor
at org.springframework.core.type.classreading.SimpleMetadataReader.<init>(SimpleMetadataReader.java:63)
at org.springframework.core.type.classreading.SimpleMetadataReaderFactory.getMetadataReader(SimpleMetadataReaderFactory.java:82)
at org.springframework.core.type.classreading.CachingMetadataReaderFactory.getMetadataReader(CachingMetadataReaderFactory.java:102)
at org.springframework.core.type.classreading.SimpleMetadataReaderFactory.getMetadataReader(SimpleMetadataReaderFactory.java:77)
at org.springframework.context.annotation.ConfigurationClassUtils.checkConfigurationClassCandidate(ConfigurationClassUtils.java:70)
at org.springframework.context.annotation.ConfigurationClassPostProcessor.processConfigBeanDefinitions(ConfigurationClassPostProcessor.java:233)
at org.springframework.context.annotation.ConfigurationClassPostProcessor.postProcessBeanDefinitionRegistry(ConfigurationClassPostProcessor.java:203)
at org.springframework.context.support.AbstractApplicationContext.invokeBeanFactoryPostProcessors(AbstractApplicationContext.java:617)
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:446)
at org.springframework.web.servlet.FrameworkServlet.configureAndRefreshWebApplicationContext(FrameworkServlet.java:631)
at org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:588)
at org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:645)
at org.springframework.web.servlet.FrameworkServlet.initWebApplicationContext(FrameworkServlet.java:508)
at org.springframework.web.servlet.FrameworkServlet.initServletBean(FrameworkServlet.java:449)
at org.springframework.web.servlet.HttpServletBean.init(HttpServletBean.java:133)
at javax.servlet.GenericServlet.init(GenericServlet.java:160)
at org.apache.catalina.core.StandardWrapper.initServlet(StandardWrapper.java:1280)
at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1193)
at org.apache.catalina.core.StandardWrapper.allocate(StandardWrapper.java:865)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:136)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:123)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:100)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:953)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1041)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:603)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:312)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
这是浏览器中抛出的异常
javax.servlet.ServletException: Servlet.init() for servlet spring threw exception
org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:100)
org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:953)
org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1041)
org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:603)
org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:312)
java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
java.lang.Thread.run(Unknown Source)
这是根本原因：
java.lang.IncompatibleClassChangeError: org/springframework/core/type/classreading/AnnotationMetadataReadingVisitor
org.springframework.core.type.classreading.SimpleMetadataReader.<init>(SimpleMetadataReader.java:63)
org.springframework.core.type.classreading.SimpleMetadataReaderFactory.getMetadataReader(SimpleMetadataReaderFactory.java:82)
org.springframework.core.type.classreading.CachingMetadataReaderFactory.getMetadataReader(CachingMetadataReaderFactory.java:102)
org.springframework.core.type.classreading.SimpleMetadataReaderFactory.getMetadataReader(SimpleMetadataReaderFactory.java:77)
org.springframework.context.annotation.ConfigurationClassUtils.checkConfigurationClassCandidate(ConfigurationClassUtils.java:70)
org.springframework.context.annotation.ConfigurationClassPostProcessor.processConfigBeanDefinitions(ConfigurationClassPostProcessor.java:233)
org.springframework.context.annotation.ConfigurationClassPostProcessor.postProcessBeanDefinitionRegistry(ConfigurationClassPostProcessor.java:203)
org.springframework.context.support.AbstractApplicationContext.invokeBeanFactoryPostProcessors(AbstractApplicationContext.java:617)
org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:446)
org.springframework.web.servlet.FrameworkServlet.configureAndRefreshWebApplicationContext(FrameworkServlet.java:631)
org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:588)
org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:645)
org.springframework.web.servlet.FrameworkServlet.initWebApplicationContext(FrameworkServlet.java:508)
org.springframework.web.servlet.FrameworkServlet.initServletBean(FrameworkServlet.java:449)
org.springframework.web.servlet.HttpServletBean.init(HttpServletBean.java:133)
javax.servlet.GenericServlet.init(GenericServlet.java:160)
org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:100)
org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:953)
org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1041)
org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:603)
org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:312)
java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
java.lang.Thread.run(Unknown Source
这些错误意味着什么以及导致它们的原因是什么？