What role does the Servlet Engine play in CQ5?
Servlet Engine acts as a server for each CQ (and CRX, if applicable) instance. Even though CQ WCM can be launched without an application server, a Servlet Engine is always required. Servlets exist in the Application Server and are controlled by the servlet engine. All servlet meta functions are handled by the servlet engine, which is an internal object. Instantiation, initialization, deletion, access from other components, and configuration management are among these functions.
The servlet engine invokes the servlet's init() method to execute any necessary initialization after the servlet is instantiated. You can override this method to conduct a servlet life initialization function, such as setting a counter. When a servlet is decommissioned, the servlet engine invokes the destroy() method in the servlet to allow the servlet to complete any remaining tasks and deallocate resources. This method can be overridden to write log messages or to wipe up any remaining connections that aren't picked up via garbage collection. The Application Server passes the incoming data to the servlet engine when a request is made. The servlet engine converts the request's input data into a HttpServletRequest request object type, which includes form data, cookies, session information, and URL name-value pairs. The HttpServletResponse response object type is also created by the servlet engine. Both are then passed as parameters to the servlet's service() procedure by the engine.
