Each servlet is associated with a servlet configuration, usually managed by the Application Server Manager. IBM has included an interesting class that maintains this information in an XML document, with the name, description, initialization parameters and a page list of your servlet. IBM provides PageListServlet and XMLServerConfig classes to make it easier to create and read the XML document. WebSphere has screens that simplify site administration and deployment tasks, letting you monitor servlet execution, connections, resource usage and response time. It also provides transaction management, security, object storage, and communications and messaging services.
GemStone provides several services over and above the servlet engine.
GemStone implements this by extending the JVM to include a persistent cache architecture. In addition to storing objects between invocation, the architecture provides a method to give state and application logic to a number of applications running on multiple Java virtual machines. JavaBeans can be spread across a number of virtual machines or extended to other servers to achieve greater performance and high availability. GemStone administrators can configure the level of transaction control that the servlet requires from the cache without additional coding. Java developers can manage nonrelational transaction integrity by responding to events raised by the GemStone environment.