Today at CERN you can host a Java web application (servlet/jsp) in a centrally managed deployment platform maintained by the IT department. The aim of the J2EE Public Service is to provide you with the necessary infrastructure and tools.

Since it went into production at the end of 2005, the J2EE Public Service has been used extensively by the CERN Java community. Today the service hosts approximately 120 Java web applications (like CERN project websites, third-party software, Java web services etc). The J2EE Public Service is widely used by physicists. For example, it hosts ATLAS web applications (to monitor and manage documentation related to the construction of the detector), various LHC web applications, and many other sites (like CERN's Technology Transfer website, shown in figure 1).

What we provide:

• A servlet and JSP container that is compatible with Servlet 2.4 and JavaServer Pages 2.0 specifications (currently Apache Tomcat 5.5). If you own a Java web application you will be assigned your own Tomcat instance.
• A series of management, configuration and monitoring tools that will enable you to manage your web application. You can deploy the application, monitor it, have access to log files and many other features via an administration web interface.
• Oracle JDBC drivers are preinstalled (thin), and NICE authentication is configured in case you need to implement access control to the web application.

Please keep in mind that the service provider will help you to deploy your web application but not to develop it.

The scope of the service

The J2EE Public Service is designed to host non-critical, medium-sized J2EE server-side applications. Mission-critical applications are not in the scope of the service: we provide full support during CERN working hours, but outside working hours support is provided on a best-effort basis (

Advantages of using the service

The J2EE Public Service is convenient for potential CERN J2EE users because it releases them from tedious maintenance tasks. We take care of the Java platform server installation, back-ups, monitoring, software upgrades and security.

Improving monitoring

Since January the service has offered a Java Management Extensions (JMX) monitoring interface to consult runtime information about web applications (e.g. memory use, CPU process time and compilation time).

This is possible thanks to the integration of JMX Monitoring Component (JMX MC) within the service. JMX MC collects this data from the Tomcat instances and feeds it into the LHC Era MONitoring (Lemon) monitoring system. This enables users to consult the data over the lifetime of their web applications, helping them to maintain and recognize any emerging problems (figure 2).

Solution to permanent storage

As many potential users of the service ask for permanent file storage, we provide, on demand, a library that uses WebDAV to connect to the Windows Distributed File System (DFS). As this solution requires modifications in the source code of the web application, we are now in the process of testing the Andrew File System (AFS) as an alternative solution.

How to start using the service

The J2EE Public Service is integrated with CERN's central web services. Creating a Java website is simple, just follow the steps explained at (figure 3).

Visit the service webpage at and join up if it fits your needs. We welcome feedback, and if you have any questions please ask us (