Apache Tomcat 8 Architecture (8.5.12) - Request Process Flow
Author: Yoav Shapira

## Request Process Flow

This page describes the process used by Tomcat to handle an incoming request. This process is largely defined by the Servlet Specification, which outlines the order of events that must take place.

#### description

TODO

#### diagrams

A UML sequence diagram of the request process is available here.

A UML sequence diagram of the authentication process is available here.

#### comments

The Servlet Specification provides many opportunities for listening in (using Listeners) or modifying (using Filters) the request handling process even before the request arrives at the servlet that will handle it.

### Comments

Notice: This comments section collects your suggestions on improving documentation for Apache Tomcat.
If you have trouble and need help, read Find Help page and ask your question on the tomcat-users mailing list. Do not ask such questions here. This is not a Q&A section.
The Apache Comments System is explained here. Comments may be removed by our moderators if they are either implemented or considered invalid/off-topic.