1. Tomcat
Celsina Bignoli

2. History of Tomcat
Tomcat is the result of the integration of two groups of developers.
JServ, an open source implementation of the Servlet specification.
Sun’s own servlet engine.
The focus of the two groups was different:
JServ concentrated on performance
Sun’s implementation was more concerned with adherence to specification.
Sun donated the code to Apache Software Foundation. A group was formed – named Jakarta - that was given a charter of merging the implementations
Tomcat was born

3. Tomcat Requirements
Strict adherence to Sun’s JSP/Servlet specification
Interoperability
Modifiability
Performance
Scalability
High-availability
Security

4. Architecture

5. Architecture
Server: Server represents the entire Tomcat server. One server per JVM.
Service: Service component creates the connectors and associates the engine with this group of connectors.
Connector: Connectors are components that implement the socket listeners. They connect web applications to clients. This component provides flexibility to the Tomcat architecture. It allows the Tomcat servlet engine to integrate with many different types of web servers such as Apache, IIS etc.
Engine: Engine is the top level container. It examines the request and routes the request to the appropriate virtual host.
Host: This allows multiple servers to be configured on the same physical machine and be identified by separate IP addresses.
Context: This represents a single web application

6. Tomcat Installation and Configuration
Install JDK1.5
Download the Jakarta Tomcat software
Set the JAVA_HOME variable
Change port from 8080 to 80 (optional)
Set the CATALINA_HOME variable

7. Changing port to 80
configure Tomcat to run on the default HTTP port (80) instead of the out-of-the-box port of 8080.
Making this change lets you use URLs of the form instead of
Some versions of Windows XP automatically start IIS on port 80.
So, if you use XP you may need to disable IIS (see the Administrative Tools section of the Control Panel).
To change the port, edit install_dir/conf/server.xml and change the port attribute of the Connector element from 8080 to 80
<Connector port="80" ...
maxThreads="150" minSpareThreads="25" ...

8. Setting CATALINA_HOME Variable
set the CATALINA_HOME environment variable to refer to the top-level directory of the Apache Tomcat installation (e.g., C:\jakarta-tomcat ).
This variable identifies the Tomcat installation directory to the server.

9. Testing the Server Involves two steps:
Verifying that the server can even start
Checking that you can access your own HTML and JSP pages
use the default Web application.
put HTML and JSP pages in install_dir/webapps/ROOT or install_dir/webapps/ROOT/somePath and access them with or

10. Setting the Development Environment
Define a working directory in which to place the servlets and JSP pages that you develop
The development directory should NOT reside in the Tomcat deployment directory

11. Making Shortcuts to Start and Stop the Server
place shortcuts to the server startup and shutdown scripts inside the main development directory or on the desktop.
Go to install_dir/bin, right-click on startup.bat, and select Copy.
go to your development directory, right-click in the window, and select Paste Shortcut (not just Paste).
Repeat the process for install_dir/bin/shutdown.bat.

12. Setting CLASSPATH
Since servlets and JSP are not part of the Java 2 platform, standard edition, you have to identify the servlet classes to the compiler.
The server already knows about the servlet classes, but the compiler (i.e., javac) you use for development probably doesn't.
Include the following jar file in the CLASSPATH
install_dir/common/lib/servlet-api.jar
install_dir/common/lib/jsp-api.jar
Alternatively you can put the above jar files in java_dir/lib/ext

13. Compiling and Testing Simple Servlets
to verify the environment is all set compile and run some simple Servlet, i.e. HelloServlet.java
the location for servlets in the default Web application is:
install_dir/webapps/ROOT/WEB-INF/classes
Once you compile HelloServlet.java, put HelloServlet.class in:
After compiling the code, access the servlet with the URL: