Preface

Spring boot uses the embedded Servlet container by default. When we use external Servlet containers, we will encounter various problems.

Environment used: IDEA + apache-tomcat-7.0.91

1.springboot starts tomcat and reports error java.lang.NoClassDefFoundError: javax/el/ELManager

Caused by: org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.springframework.validation.beanvalidation.LocalValidatorFactoryBean]: Factory method 'defaultValidator' threw exception; nested exception is java.lang.NoClassDefFoundError: javax/el/ELManager
	at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:185)
	at javax.management.remote.rmi.RMIConnectionImpl.doOperation(RMIConnectionImpl.java:1468) [na:1.8.0_121]
	at javax.management.remote.rmi.RMIConnectionImpl.access$300(RMIConnectionImpl.java:76) [na:1.8.0_121]
	at javax.management.remote.rmi.RMIConnectionImpl$PrivilegedOperation.run(RMIConnectionImpl.java:1309) [na:1.8.0_121]
	at java.security.AccessController.doPrivileged(Native Method) [na:1.8.0_121]
	at javax.management.remote.rmi.RMIConnectionImpl.doPrivilegedOperation(RMIConnectionImpl.java:1408) [na:1.8.0_121]
	at javax.management.remote.rmi.RMIConnectionImpl.invoke(RMIConnectionImpl.java:829) [na:1.8.0_121]
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_121]
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_121]
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_121]
	at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_121]
	at sun.rmi.server.UnicastServerRef.dispatch(UnicastServerRef.java:346) [na:1.8.0_121]
	at sun.rmi.transport.Transport$1.run(Transport.java:200) [na:1.8.0_121]
	at sun.rmi.transport.Transport$1.run(Transport.java:197) [na:1.8.0_121]
	at java.security.AccessController.doPrivileged(Native Method) [na:1.8.0_121]
	at sun.rmi.transport.Transport.serviceCall(Transport.java:196) [na:1.8.0_121]
	at sun.rmi.transport.tcp.TCPTransport.handleMessages(TCPTransport.java:568) [na:1.8.0_121]
	at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run0(TCPTransport.java:826) [na:1.8.0_121]
	at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.lambda$run$0(TCPTransport.java:683) [na:1.8.0_121]
	at java.security.AccessController.doPrivileged(Native Method) [na:1.8.0_121]
	at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run(TCPTransport.java:682) [na:1.8.0_121]
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) ~[na:1.8.0_121]
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) ~[na:1.8.0_121]
	at java.lang.Thread.run(Thread.java:745) ~[na:1.8.0_121]
Caused by: org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.springframework.validation.beanvalidation.LocalValidatorFactoryBean]: Factory method 'defaultValidator' threw exception; nested exception is java.lang.NoClassDefFoundError: javax/el/ELManager
	at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:185) ~[spring-beans-5.2.3.RELEASE.jar:5.2.3.RELEASE]
	at org.springframework.beans.factory.support.ConstructorResolver.instantiate(ConstructorResolver.java:651) ~[spring-beans-5.2.3.RELEASE.jar:5.2.3.RELEASE]
	... 66 common frames omitted
	at org.springframework.beans.factory.support.ConstructorResolver.instantiate(ConstructorResolver.java:651)
	... 66 more
Caused by: java.lang.NoClassDefFoundError: javax/el/ELManager
	at org.hibernate.validator.messageinterpolation.ResourceBundleMessageInterpolator.buildExpressionFactory(ResourceBundleMessageInterpolator.java:88)
	at org.hibernate.validator.messageinterpolation.ResourceBundleMessageInterpolator.<init>(ResourceBundleMessageInterpolator.java:47)
	at org.hibernate.validator.internal.engine.ConfigurationImpl.getDefaultMessageInterpolator(ConfigurationImpl.java:474)
	at org.springframework.boot.validation.MessageInterpolatorFactory.getObject(MessageInterpolatorFactory.java:53)
	at org.springframework.boot.autoconfigure.validation.ValidationAutoConfiguration.defaultValidator(ValidationAutoConfiguration.java:57)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:498)
	at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:154)
	... 67 more

Analysis:

There are many contents of error reporting, but the key is Caused by: java.lang.NoClassDefFoundError: javax/el/ELManager, which has been a problem for a long time, has copied the El API in IDEA to tomcat, and has modified the catalina.properties file under Tomcat. It is found that because the version of IDEA is relatively high (the version of Tomcat is also relatively high, so there is no El API file at all), the configuration file still reports an error after modification.
Baidu has been on the Internet for a long time, only to know that the decompilation El API does not have ElManager, and it was introduced in el-api3.0 (because the tomcat version we use is too low). We can download it directly
javax.el-api-3.0-b07.jar, put it under tomcat/lib (another is to use tomcat8)

2. Spring boot launches jsp page to report error java.lang.NoSuchMethodError: javax.el.ExpressionFactory.newInstance()Ljavax/el/ExpressionFactory

javax.servlet.ServletException: java.lang.NoSuchMethodError: javax.el.ExpressionFactory.newInstance()Ljavax/el/ExpressionFactory;
	at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:348) ~[jasper.jar:7.0.91]
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:731) ~[servlet-api.jar:na]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303) [catalina.jar:7.0.91]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) [catalina.jar:7.0.91]
	at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) ~[tomcat7-websocket.jar:7.0.91]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241) [catalina.jar:7.0.91]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) [catalina.jar:7.0.91]
	at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:100) ~[spring-web-5.2.3.RELEASE.jar:5.2.3.RELEASE]
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119) [spring-web-5.2.3.RELEASE.jar:5.2.3.RELEASE]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241) [catalina.jar:7.0.91]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) [catalina.jar:7.0.91]
	at org.springframework.web.filter.FormContentFilter.doFilterInternal(FormContentFilter.java:93) ~[spring-web-5.2.3.RELEASE.jar:5.2.3.RELEASE]
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119) [spring-web-5.2.3.RELEASE.jar:5.2.3.RELEASE]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241) [catalina.jar:7.0.91]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) [catalina.jar:7.0.91]
	at org.springframework.boot.web.servlet.support.ErrorPageFilter.doFilter(ErrorPageFilter.java:128) [spring-boot-2.2.4.RELEASE.jar:2.2.4.RELEASE]
	at org.springframework.boot.web.servlet.support.ErrorPageFilter.access$000(ErrorPageFilter.java:66) [spring-boot-2.2.4.RELEASE.jar:2.2.4.RELEASE]
	at org.springframework.boot.web.servlet.support.ErrorPageFilter$1.doFilterInternal(ErrorPageFilter.java:103) [spring-boot-2.2.4.RELEASE.jar:2.2.4.RELEASE]
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119) [spring-web-5.2.3.RELEASE.jar:5.2.3.RELEASE]
	at org.springframework.boot.web.servlet.support.ErrorPageFilter.doFilter(ErrorPageFilter.java:121) [spring-boot-2.2.4.RELEASE.jar:2.2.4.RELEASE]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241) [catalina.jar:7.0.91]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) [catalina.jar:7.0.91]
	at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:201) [spring-web-5.2.3.RELEASE.jar:5.2.3.RELEASE]
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119) [spring-web-5.2.3.RELEASE.jar:5.2.3.RELEASE]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241) [catalina.jar:7.0.91]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) [catalina.jar:7.0.91]
	at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:219) [catalina.jar:7.0.91]
	at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:110) [catalina.jar:7.0.91]
	at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:494) [catalina.jar:7.0.91]
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:169) [catalina.jar:7.0.91]
	at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:104) [catalina.jar:7.0.91]
	at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:1025) [catalina.jar:7.0.91]
	at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116) [catalina.jar:7.0.91]
	at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:445) [catalina.jar:7.0.91]
	at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1137) [tomcat-coyote.jar:7.0.91]
	at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:637) [tomcat-coyote.jar:7.0.91]
	at org.apache.tomcat.util.net.AprEndpoint$SocketProcessor.doRun(AprEndpoint.java:2555) [tomcat-coyote.jar:7.0.91]
	at org.apache.tomcat.util.net.AprEndpoint$SocketProcessor.run(AprEndpoint.java:2544) [tomcat-coyote.jar:7.0.91]
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) [na:1.8.0_121]
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) [na:1.8.0_121]
	at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) [tomcat-coyote.jar:7.0.91]
	at java.lang.Thread.run(Thread.java:745) [na:1.8.0_121]
Caused by: java.lang.NoSuchMethodError: javax.el.ExpressionFactory.newInstance()Ljavax/el/ExpressionFactory;
	at org.apache.jasper.compiler.PageInfo.<init>(PageInfo.java:79) ~[jasper.jar:7.0.91]
	at org.apache.jasper.compiler.Compiler.generateJava(Compiler.java:111) ~[jasper.jar:7.0.91]
	at org.apache.jasper.compiler.Compiler.compile(Compiler.java:374) ~[jasper.jar:7.0.91]
	at org.apache.jasper.compiler.Compiler.compile(Compiler.java:354) ~[jasper.jar:7.0.91]
	at org.apache.jasper.compiler.Compiler.compile(Compiler.java:341) ~[jasper.jar:7.0.91]
	at org.apache.jasper.JspCompilationContext.compile(JspCompilationContext.java:660) ~[jasper.jar:7.0.91]
	at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:378) ~[jasper.jar:7.0.91]
	at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:395) ~[jasper.jar:7.0.91]
	at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:339) ~[jasper.jar:7.0.91]
	... 41 common frames omitted

Analysis:

On the Internet, it's a toss and turn out to be the lack of com.sun.el.ExpressionFactoryImpl, so there's no corresponding method, and then we found several jar packages related to it.
Solution: put juel.jar, juel-engine.jar, juel-impl.jar in our tomcat lib directory
The above 4 jar packages can pass the https://www.mvnjar.com/ Downloading

Conclusion:

When spring boot uses tomcat of external Servlet container, try to use version 8.0 or above, otherwise you will find that various jar packages will be missing.