The environment

  • Linux/Ubuntu20.04 LTS
  • IntelliJ IDEA Community Editon 2021.1
  • Apache tomcat — 8.5.68


java.lang.NoSuchMethodException: org.apache.catalina.deploy.WebXml addServlet

Critical: flags the current application as unavailable due to a previous error

Serious: Context[/ Oasys] failed to start due to a previous error

Severe: analytical application of web. XML error, location: [jndi: / localhost/OASYS/web - INF/web. XML]
Caused by: org.apache.catalina.LifecycleException: Cannot start the component [standardEngine [Catalina].standardHost [localhost].standardContext [/SSH]] June 29, 2021 9:37:27 afternoon org. Apache. Catalina. Startup. Catalina start http://localhost:8077/SSH serious: the necessary service components failed to start, so I can't start Tomcat


  1. The jar conflicts
  2. The project web.xml configuration error
  3. There is a problem with the Tomcat server

Analysis of the

  • The project used to run and changed something to make it unrunnable, but the web.xml was not modified, so the project is configured correctly
  • JAR scrutiny does not reveal missing or conflicting issues
  • Without the project, Tomcat can be run locally, so Tomcat is fine
  • The Context[/XXX] failed to start due to a previous error, so there will be a problem when running the project, either with the project or with a Tomcat configuration problem


In the tomcat directory conf/context.xml

Add <Loader delegate=”true” /> to context.xml

<! -- creat by layuji on 2021-07-01 --> <Loader delegate="true" />

In the rainy season, eat the rainbow