How to debug a tomcat under the servlet

Tomcat's default is that the Servlet class file cannot be opened directly. By modifying the configuration file we can achieve, and can easily debug the servlet.

The method is simple:

Modify the Web.xml file in the Tomcat directory below, and remove the two-paragraph annotation:

<!--
<servlet>
<servlet-name>invoker</servlet-name>
<servlet-class>
Org.apache.catalina.servlets.InvokerServlet
</servlet-class>
<init-param>
<param-name>debug</param-name>
<param-value>0</param-value>
</init-param>
<load-on-startup>2</load-on-startup>
</servlet>
-->

And

<!--
<servlet-mapping>
<servlet-name>invoker</servlet-name>
<url-pattern>/servlet/*</url-pattern>
</servlet-mapping>
-->

If you start Tomcat again, you can access it directly in your browser.
Http://localhost:8080/testWeb/servlet/test.HelloWorld

Description: localhost:8080 is the address and port number of the server, TestWeb is the deployment package, the servlet is the specified access type is a servlet, the last Test. HelloWorld is the real servlet file.