为何无法访问Tomcat中/webapps/Root下的xx.jsp文件？

Hey there! Let's break down why your xx.jsp is throwing a 404 error while xx.html loads just fine—here are the most common causes and fixes to check:

• Incorrect file placement
  Make sure your xx.jsp is in the right directory. If you're accessing it via http://localhost:8080/xx.jsp, it needs to live directly in the ROOT folder (same location as the working index.jsp). If you put it in a subfolder, you'll need to include that path in your URL, like http://localhost:8080/your-subfolder/xx.jsp.

• Missing JSP servlet mapping
  Tomcat relies on a built-in servlet to process .jsp files. Check your Tomcat conf/web.xml file for this default mapping—if it's missing or modified, Tomcat won't know how to handle JSP requests. Look for this section:

  <servlet>
      <servlet-name>jsp</servlet-name>
      <servlet-class>org.apache.jasper.servlet.JspServlet</servlet-class>
  </servlet>
  <servlet-mapping>
      <servlet-name>jsp</servlet-name>
      <url-pattern>*.jsp</url-pattern>
      <url-pattern>*.jspx</url-pattern>
  </servlet-mapping>
  

  If it's not there, add it back (you might need to restart Tomcat afterward).

• File extension typos
  Double-check the exact filename—case matters on systems like Linux. Accidental typos like xx.JSP or xx.js will cause a 404, since Tomcat only recognizes lowercase .jsp by default. HTML files are more forgiving because they're served as static content regardless of case (usually).

• Tomcat didn't detect the new file
  If you added the JSP while Tomcat was running, try restarting the server. Some configurations don't auto-detect new JSP files on the fly. You can also verify if autoDeploy="true" is set in the <Host> element of your conf/server.xml—this enables automatic deployment of new files without a restart.

• File permission issues
  Ensure the Tomcat process has read access to your xx.jsp file. On Linux/macOS, run chmod 644 xx.jsp to set read permissions, and chown tomcat:tomcat xx.jsp (adjust the user/group to match your Tomcat setup) to give the server ownership. On Windows, make sure the file isn't marked as read-only.

内容的提问来源于stack exchange，提问作者wuhui