A Realm is a "database" of usernames and passwords that identify valid users of a web application (or set of web applications), plus an enumeration of the list of roles associated with each valid user. JDBCRealm is an implementation of the Tomcat 5 Realm interface that looks up users in a relational database accessed via a JDBC driver.

JNDI resource configuration has changed somewhat between Tomcat 5.0.x and Tomcat 5.5.x In this tutorial we will use MySQL database.

To upload file in JSP environment we can use commons-fileupload library from apache Jakarta projects

Standard tag can control jsp pages at runtime. There is standard tag and custom tag in jsp. Standard tag is define by jsp specification, custom tag is a new tag can be defined by our own

Step by step article creating JSP pages chapter 1

Velocity is a template engine in Java environment produced by Apache Jakarta Project . With velocity we use a template file (html layout) rather than drawing html tags with println in Java servlets.

Tomcat has built in Java Database Connection Pooling (JDCP). This means, Tomcat can provides connection pooling, that can be mapped into JNDI. This article describes Step by step tutorial, howto connecting servlet with MySQL database trough JNDI Datasource in Tomcat.

You should read previous article before applying this tutorial