javax.servlet.ServletException: Servlet[dispatcher]的Servlet.init（）引发异常----解决方法

问题：报500错：


类型 异常报告

消息 Servlet[dispatcher]的Servlet.init（）引发异常

描述 服务器遇到一个意外的情况，阻止它完成请求。

例外情况

javax.servlet.ServletException: Servlet[dispatcher]的Servlet.init（）引发异常
	org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:492)
	org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:93)
	org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:673)
	org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:360)
	org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:399)
	org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:63)
	org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:926)
	org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1791)
	org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
	org.apache.tomcat.util.threads.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1191)
	org.apache.tomcat.util.threads.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:659)
	org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
	java.base/java.lang.Thread.run(Thread.java:1589)
根本原因。

org.springframework.beans.factory.BeanDefinitionStoreException: Failed to read candidate component class: file [D:\CS\TomCat\apache-tomcat-9.0.72-windows-x64\apache-tomcat-9.0.72\webapps\springMVC_demo_war\WEB-INF\classes\com\dong\controller\UserController.class]; nested exception is org.springframework.core.NestedIOException: ASM ClassReader failed to parse class file - probably due to a new Java class file version that isn't supported yet: file [D:\CS\TomCat\apache-tomcat-9.0.72-windows-x64\apache-tomcat-9.0.72\webapps\springMVC_demo_war\WEB-INF\classes\com\dong\controller\UserController.class]; nested exception is java.lang.IllegalArgumentException: Unsupported class file major version 63
	org.springframework.context.annotation.ClassPathScanningCandidateComponentProvider.scanCandidateComponents(ClassPathScanningCandidateComponentProvider.java:452)
	org.springframework.context.annotation.ClassPathScanningCandidateComponentProvider.findCandidateComponents(ClassPathScanningCandidateComponentProvider.java:315)
	org.springframework.context.annotation.ClassPathBeanDefinitionScanner.doScan(ClassPathBeanDefinitionScanner.java:276)
	org.springframework.context.annotation.ComponentScanAnnotationParser.parse(ComponentScanAnnotationParser.java:132)
	org.springframework.context.annotation.ConfigurationClassParser.doProcessConfigurationClass(ConfigurationClassParser.java:296)
	org.springframework.context.annotation.ConfigurationClassParser.processConfigurationClass(ConfigurationClassParser.java:250)
	org.springframework.context.annotation.ConfigurationClassParser.parse(ConfigurationClassParser.java:207)
	org.springframework.context.annotation.ConfigurationClassParser.parse(ConfigurationClassParser.java:175)
	org.springframework.context.annotation.ConfigurationClassPostProcessor.processConfigBeanDefinitions(ConfigurationClassPostProcessor.java:331)
	org.springframework.context.annotation.ConfigurationClassPostProcessor.postProcessBeanDefinitionRegistry(ConfigurationClassPostProcessor.java:247)
	org.springframework.context.support.PostProcessorRegistrationDelegate.invokeBeanDefinitionRegistryPostProcessors(PostProcessorRegistrationDelegate.java:311)
	org.springframework.context.support.PostProcessorRegistrationDelegate.invokeBeanFactoryPostProcessors(PostProcessorRegistrationDelegate.java:112)
	org.springframework.context.support.AbstractApplicationContext.invokeBeanFactoryPostProcessors(AbstractApplicationContext.java:746)
	org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:564)
	org.springframework.web.servlet.FrameworkServlet.configureAndRefreshWebApplicationContext(FrameworkServlet.java:702)
	org.springframework.web.servlet.FrameworkServlet.initWebApplicationContext(FrameworkServlet.java:578)
	org.springframework.web.servlet.FrameworkServlet.initServletBean(FrameworkServlet.java:530)
	org.springframework.web.servlet.HttpServletBean.init(HttpServletBean.java:170)
	javax.servlet.GenericServlet.init(GenericServlet.java:158)
	org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:492)
	org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:93)
	org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:673)
	org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:360)
	org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:399)
	org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:63)
	org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:926)
	org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1791)
	org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
	org.apache.tomcat.util.threads.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1191)
	org.apache.tomcat.util.threads.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:659)
	org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
	java.base/java.lang.Thread.run(Thread.java:1589)

解决方法

你的jdk版本太高了，降到17以下，我改成16，就成功了

在maven里即，pom.xml文件里添加代码：

 <properties>
    <maven.compiler.source>16</maven.compiler.source>
    <maven.compiler.target>16</maven.compiler.target>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
  </properties>