It is always recommended.
Chapter 9, "Database Connectivity".
Null) ose private Connection establishConnection / partnersuche kostenlos und seriös Not implemented.
By default container follows Multi Thread Model.
By instead implementing SingleThreadModel and having one "connection" instance variable per servlet, a servlet can easily handle concurrent requests by letting its server manage the servlet instance pool (which doubles as a connection pool).Copyright 2001, o'Reilly Associates.The life cycle can be useful, however, in avoiding synchronization while still performing efficient request handling.So no use of maintaining many instance for long time.public class SingleThreadConnection extends HttpServlet implements SingleThreadModel Connection con null; / database connection, one per pooled servlet instance public void init(ServletConfig config) throws ServletException it(config / Establish the connection for this instance con establishConnection tAutoCommit(false public void doGet(HttpServletRequest req, HttpServletResponse res) throws ServletException, IOException tContentType.Thus, any servlet implementing SingleThreadModel can be considered thread safe and isn't required to synchronize access to its instance variables.Normally, this would require the servlet to synchronize around the database commands (letting it manage just one request at a time) or to manage a pool of database connections where it can "check out" and "check in" connections (letting it support multiple concurrent requests).The skeleton code is shown.
Only one servlet instance will be created and the same instance will be used to provide the service to every incoming service.
Container create one or more servlet instance depending on which servlet model you are using.
In the case of single Thread Model servlet instance will be created for every incoming request that is multiple servlet instance will be created for Single Thread Model.
Such servlets indicate this desire by implementing the ngleThreadModel interface.
Although it is standard to have one servlet instance per registered servlet name, it is possible for a servlet to elect instead to have a pool of instances created for each of its names, all sharing the duty of handling requests.Such a life cycle is pointless for a counter or other servlet application that requires central state maintenance.Handling database connections using SingleThreadModel import.The Single Thread Model.This is an empty, tag interface that defines no methods or variables and serves only to flag the servlet as wanting the alternate life cycle.It is not recommendable to use SingleThreadModel because multiple instance of a servlet will not be reused.For example, a servlet that connects to a database sometimes needs to perform several database commands atomically as part of a single transaction.A server that loads a SingleThreadModel servlet must guarantee, according to the Servlet API documentation, "that no two threads will execute concurrently the service method of that servlet." To accomplish this, each thread uses a free servlet instance from the pool, as shown.There are two servlet model: Single Thread Model, multi Thread Model, single Thread Model: To follow single Thread model your servlet class has to implement interface called is a marker interface.This is may be cause the problem like performance memory wastage.