001 /** =====================================================================
002 *
003 * File Name : $Id: DBCPoolingListener.java,v 1.3 2008/01/15 11:08:15 cb Exp $
004 *
005 * Description
006 * -----------
007 *
008 * See javadoc comment
009 *
010 * =====================================================================
011 *
012 * @Author : Craige Bevil
013 * Control Software Group
014 * Isaac Newton Group of Telescopes
015 *
016 * =====================================================================
017 *
018 * Modification Log
019 *
020 * Vers Date Author Reason
021 * ---- ---- ------ ------
022 * 1 9 May 2007 C.Bevil First Release
023 *
024 * Commissioning Notes
025 * -------------------
026 *
027 * None
028 *
029 * =====================================================================
030 *
031 * @Version : $Id: DBCPoolingListener.java,v 1.3 2008/01/15 11:08:15 cb Exp $
032 *
033 * @Author : $Author: cb $
034 *
035 * Header : $Header: /opt/INGsrc/src/CVS/softproj/FaultDatabase/src/FaultDatabase/FaultDatabase/src/GWTApplication/server/DBCPoolingListener.java,v 1.3 2008/01/15 11:08:15 cb Exp $
036 *
037 * Log : $Log: DBCPoolingListener.java,v $
038 * Log : Revision 1.3 2008/01/15 11:08:15 cb
039 * Log : Ran through PMD and sorted out the javadoc so that we could export the
040 * Log : javadoc to the javadoc repository.
041 * Log :
042 * Log : Revision 1.2 2007/08/01 13:00:03 cb
043 * Log : First prototype after import
044 * Log :
045 * Log : Revision 1.1.1.1 2007/06/01 08:33:25 cb
046 * Log : Imported using TkCVS
047 * Log :
048 *
049 * =====================================================================*/
050
051 package GWTApplication.server;
052
053 import javax.servlet.*;
054 import javax.naming.*;
055 import javax.sql.DataSource;
056
057 /**
058 * This is a class which will be called by Tomcat when the servlet for
059 * the fault database is loaded by the container and will result in
060 * the database connection pool being initialised. The servlet when
061 * connecting to the database will use a connection from the database
062 * pool so as to accelerate the database access.
063 * @author Craige Bevil
064 * @version $Id: DBCPoolingListener.java,v 1.3 2008/01/15 11:08:15 cb Exp $
065 */
066
067 public class DBCPoolingListener implements ServletContextListener {
068
069 /**
070 * This is called when the fault database context is created in
071 * the servlet and serves to initialise the database pool intended
072 * to be used by the fault management system in the tomcat
073 * servlet. It looks up the data source in the tomcat container
074 * which will provide the handle through which we will get
075 * database connections.
076 *<P>
077 * The configuration data for the pool (pertinent to the fault management system) is stored within the tomcat configuration data.
078 * @param sce This is the details of the servlet context event.
079 */
080
081 public void contextInitialized (ServletContextEvent sce) {
082
083 try {
084
085 // Obtain our environment naming context
086
087 Context envCtx = (Context) new InitialContext().lookup("java:comp/env");
088
089 // Look up our data source which is a connection to the
090 // postgres database
091
092 DataSource ds = (DataSource) envCtx.lookup("jdbc/faultDBAccess");
093
094 sce.getServletContext().setAttribute("DBCPool", ds);
095
096 } catch(NamingException e){
097 e.printStackTrace();
098 }
099 }
100
101 public void contextDestroyed(ServletContextEvent sce){
102 }
103 }