在 Apache Tomcat 上运行 Spring-Boot Web App 时出现 500 Servlet 错误 - 无法删除类文件

Question

I have been working on developing a web app using spring-boot, but suddenly ran into a possible permissions issue when deploying with apache tomcat (9.0.36). None of the code has changed, but suddenly Jasper cannot compile my JSP class files. It looks like it is trying to delete class files in the tomcat deployment directory, but fails.

I am not sure what could be causing this, but it happens both when running it through MyEclipse Tomcat, and using the embedded Tomcat server with Maven's spring-boot:run command. Here is an example of the error:

Fri Sep 04 11:04:00 EDT 2020
There was an unexpected error (type=Internal Server Error, status=500).
Unable to delete class file

Stack Trace:

2020-09-08 16:37:26.192 ERROR 21236 --- [nio-8080-exec-1] o.a.c.c.C.[.[localhost].[/].[jsp]        : Servlet.service() for servlet [jsp] in context with path [] threw exception [org.apache.jasper.JasperException: Unable to compile class for JSP] with root cause

java.io.IOException: Unable to delete class file [C:\Users\ek040e\Documents\Work\apache-tomcat-9.0.36\work\Catalina\localhost\ROOT\org\apache\jsp\index_jsp.class]
    at org.apache.jasper.compiler.SmapUtil$SDEInstaller.install(SmapUtil.java:180) ~[jasper.jar:9.0.36]
    at org.apache.jasper.compiler.SmapUtil.installSmap(SmapUtil.java:142) ~[jasper.jar:9.0.36]
    at org.apache.jasper.compiler.JDTCompiler.generateClass(JDTCompiler.java:543) ~[jasper.jar:9.0.36]
    at org.apache.jasper.compiler.Compiler.compile(Compiler.java:392) ~[jasper.jar:9.0.36]
    at org.apache.jasper.compiler.Compiler.compile(Compiler.java:362) ~[jasper.jar:9.0.36]
    at org.apache.jasper.compiler.Compiler.compile(Compiler.java:346) ~[jasper.jar:9.0.36]
    at org.apache.jasper.JspCompilationContext.compile(JspCompilationContext.java:605) ~[jasper.jar:9.0.36]
    at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:400) ~[jasper.jar:9.0.36]
    at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:385) ~[jasper.jar:9.0.36]
    at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:329) ~[jasper.jar:9.0.36]
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:741) ~[servlet-api.jar:na]
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231) ~[catalina.jar:9.0.36]
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[catalina.jar:9.0.36]
    at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53) ~[tomcat-websocket.jar:9.0.36]
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[catalina.jar:9.0.36]
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[catalina.jar:9.0.36]
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:202) ~[catalina.jar:9.0.36]
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96) [catalina.jar:9.0.36]
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:541) [catalina.jar:9.0.36]
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:139) [catalina.jar:9.0.36]
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92) [catalina.jar:9.0.36]
    at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:690) [catalina.jar:9.0.36]
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:74) [catalina.jar:9.0.36]
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:343) [catalina.jar:9.0.36]
    at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:373) [tomcat-coyote.jar:9.0.36]
    at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65) [tomcat-coyote.jar:9.0.36]
    at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:868) [tomcat-coyote.jar:9.0.36]
    at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1590) [tomcat-coyote.jar:9.0.36]
    at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) [tomcat-coyote.jar:9.0.36]
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) [na:1.8.0_112]
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) [na:1.8.0_112]
    at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) [tomcat-util.jar:9.0.36]
    at java.lang.Thread.run(Thread.java:745) [na:1.8.0_112]

Answer 1

Stuff like this happens on local boxes. It could be your antivirus or some other process on your computer or parallel threads in your IDE. I wouldn't worry about it until it starts happening on a prod box. Sometimes you just need to nuke the whole thing and start over, especially when using eclipse. I wouldnt worry too much about it so long as everything works properly via maven and the command line.