struts-config.xml에 내 자신의 연결 풀을 초기화하는 방법은 무엇입니까?

Question

난 내 자신의 연결 풀 클래스

public class ConnectionPool { 


private static final Logger log = Logger.getLogger(ConnectionPool.class); 

public final static String PROPERTIES_FILENAME = "config"; 
public static final int DEFAULT_POOL_SIZE = 10; 


//single instance 
private static ConnectionPool instatance; 
//queue of free connections 
private BlockingQueue<Connection> connectionQueue; 

public ConnectionPool(String driver, String url, String user, 
     String password, int poolSize) 
     throws ClassNotFoundException, DAOException{ 
    try{ 
     Class.forName(driver); 
     connectionQueue = new ArrayBlockingQueue<Connection>(poolSize); 
     for(int i = 0; i < poolSize ;i++){ 
      Connection connection = DriverManager.getConnection(url, user, password); 
      connectionQueue.offer(connection); 
     } 
    } 
    catch (SQLException e) { 
     log.error(e); 
     throw new DAOException(e.getMessage()); 
    } 
} 

public static void init() throws DAOException{ 
    try { 
    if(instatance == null){ 


     String driver = ConfigurationManager. 
     getInstance().getProperty("DATABASE_DRIVER_NAME"); 
     String url = ConfigurationManager. 
     getInstance().getProperty("DATABASE_URL"); 
     String user = ConfigurationManager. 
     getInstance().getProperty("DATABASE_USER"); 
     String password = ConfigurationManager. 
     getInstance().getProperty("DATABASE_PASSWORD"); 
     String poolSizeStr = ConfigurationManager. 
     getInstance().getProperty("DATABASE_POOLSIZE"); 
     int poolSize = (poolSizeStr != null) ? 
       Integer.parseInt(poolSizeStr) : DEFAULT_POOL_SIZE; 

     log.info("Trying to create pool of connections..."); 

     instatance = new ConnectionPool(driver,url,user,password,poolSize); 

     log.info("Connection pool initialized"); 
    } 
    }catch (ClassNotFoundException e) { 
     log.error(e); 
    } catch (SQLException e) { 
     log.error(e); 
     throw new DAOException(e.getMessage()); 
    } 
} 

public static void dispose() throws DAOException { 
    try { 
     if(instatance != null){ 
      instatance.clearConnectionQueue(); 
      instatance = null; 
      log.info("Connection queue is disposed"); 
     } 
    } catch (DAOException e) { 
     log.info(e.getMessage()); 
     throw new DAOException(e.getMessage()); 
    } 
} 

public static ConnectionPool getInstance(){ 
    return instatance; 
} 

public Connection takeConnection() { 
    Connection connection = null; 
    try{ 
     connection = connectionQueue.take(); 
    }catch (InterruptedException e) { 
     log.info("Free connection waiting interrupted.Returned null connection"); 
     log.error(e); 
    } 
    return connection; 
} 

public void releaseConnection(Connection connection) throws DAOException { 
    try { 

     if(!connection.isClosed()){ 
      if(!connectionQueue.offer(connection)){ 
       log.info("Connections is not added."); 
      } 
     } 
     else{ 
      log.info("Trying to release closed connection."); 
     } 
    } catch (SQLException e) { 
     log.info("SQLException at connection isClosed(). Connection is not added"); 
     throw new DAOException(e.getMessage()); 
    } 
} 

private void clearConnectionQueue() throws DAOException{ 
    try { 
     Connection connection; 
     while((connection = connectionQueue.poll()) != null){ 

      if(!connection.getAutoCommit()){ 
       connection.commit(); 
       connection.close(); 
      } 
    } 
    } catch (SQLException e) { 
     log.info(e.getMessage()); 
     throw new DAOException(e.getMessage()); 
    } 
} 

이 있고이 스트럿 서블릿의 라이프 사이클의 시작에서 초기화해야합니다. 그것은 일반 서블릿 있다면 나는 init() 방법은 생각하지 사용했던, 나는 그것을 할 거라고 :

public class LinkAction extends DispatchAction { 
private static final String PARAM_NAME_LANGUAGE = "language"; 

/** 
* This is the Struts action method called on 
* http://.../actionPath?method=myAction1, 
* where "method" is the value specified in <action> element : 
* (<action parameter="method" .../>) 
*/ 
private static ConnectionPool connectionPool = 
    ConnectionPool.getInstance(); 

public void init(){ 
    try { 
     if(connectionPool == null){ 

      ConnectionPool.init(); 
      connectionPool = ConnectionPool.getInstance(); 
     } 

    } catch (DAOException e) { 
     log.error(e); 
    } 
} 


public ActionForward newsList(ActionMapping mapping, ActionForm form, 
     HttpServletRequest request, HttpServletResponse response) 
     throws Exception { 

    return mapping.findForward("newsList"); 
} 

public ActionForward addNews(ActionMapping mapping, ActionForm form, 
     HttpServletRequest request, HttpServletResponse response) 
     throws Exception { 

    return mapping.findForward("addNews"); 
} 

public ActionForward changeLocale(ActionMapping mapping, ActionForm form, 
     HttpServletRequest request, HttpServletResponse response) 
     throws Exception { 
    String localeValue = request.getParameter("localeValue"); 
    request.getSession().setAttribute(PARAM_NAME_LANGUAGE, localeValue); 
    return mapping.findForward("newsList"); 
} 


} 

그러나 이것은 Struts 액션 작동하지 않습니다, 그래서 그것이 struts-config.xml 또는에서 수행 될 수 있다는 결정 web.xml. 그러나 어떻게?

Answer 1

나는 당신이 ServletContextListener를 사용해야한다고 생각 : 다른 프레임 워크를 사용하여

http://docs.oracle.com/javaee/6/api/javax/servlet/ServletContextListener.html

경우에도이 데이터 소스 초기화 코드를 넣을 수있는 좋은 장소입니다. 이 리스너는 응용 프로그램이 실행될 때마다 호출되어 데이터 소스를 컨텍스트 특성에 넣고 필요할 때마다 복구 할 수 있습니다.