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Struts & Hibernate
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| | | Struts and JNDI | Struts and JNDI 2007-09-04 - By Mary Poppins
Back
Ray thanks for your response. I have solved the problem. FYI, I based the
ThreadLocal variable solution on the HibernateUtil class developed by
Christian Bauer one of the Hibernate Developers.
The problem arose form another application that was being initialised
directly after my web app. This application was changing the initial
context, so when I retrieved it again in the application it didn't have any
reference to java:comp. As I didn't need this other application I simply
undelpoyed it, but I guess there is some way that I could have initialised
the InitialContext class to select the correct context, but I'm not sure how
this is done. I'll have a look at it again when I have more time.
Thanks again for your reply
Ray Clough wrote:
>
> (Mary Poppins: 'Practically Perfect in Every Way')
>
> This is a complicated scenario, what with a private static final
> ThreadLocal in a class with a public constructor. Without coding it and
> tracing the ThreadLocal context, my guess is that the ThreadLocal is not
> being carried thru the various requests, as it is specific to the thread
> which created it, even though as a static final object, you would normally
> expect it to exist for all class instances. You might try 2 things: (1)
> make the class a singleton, and remove the ThreadLocal context for the
> Factory, or (2) use the 'ServiceLocator' pattern from the 'Core J2EE
> Patterns' book, now available on-line from Sun.
>
> Is there a reason to use ThreadLocal context here?
>
> Sorry I couldn't be more helpful.
>
> - Ray Clough
>
>
>
>> -- -- Original Message -- --
>> From: "Mary Poppins" <sean.mcelroy@(protected)>
>> To: user@(protected)
>> Subject: Struts and JNDI
>> Date: Mon, 3 Sep 2007 05:57:30 -0700 (PDT)
>>
>>
>>
>> I have a struts application, deployed using tomcat 5, that uses database
>> pooling. I have a helper class called DAOhelper that encapsulates
>> database
>> interactions. The problem I have is that the class only works during
>> application initialisation. I have an ApplicationInitaliser class that
>> extends Plugin. In this class I can use my DAOHelper to acces the
>> database,
>> however the class does not work when invoked in an action.
>>
>> The DAOhelper class contains the following method
>>
>> private static DataSource getDataSource() throws DAOException
>> {
>> logger.debug(IConstants.ENTERING);
>> DataSource dataSource = null;
>>
>> try
>> {
>> Context initCtx = new InitialContext();
>> Context envCtx = (Context) initCtx.lookup("java:comp/env");
>>
>> //Look up our data source
>> dataSource = (DataSource)envCtx.lookup("jdbc/Frontline");
>>
>> logger.debug("DataSource retrieved successfully");
>> }
>> catch (NamingException e)
>> {
>> String errorMessage = IConstants.DATA_SOURCE_ERROR + " using context
>> jdbc/Frontline";
>> logger.error(errorMessage);
>> logger.error(e.getMessage(),e);
>> throw new DAOException(errorMessage,e);
>> }
>>
>> logger.debug(IConstants.EXITING);
>> return dataSource;
>> }
>>
>> The line Context envCtx = (Context) initCtx.lookup("java:comp/env");
>> throws
>> a javax.naming.NameNotFoundException when the class is used inside an
>> action, but works fine during initialising in the init method.
>>
>> The excpetion message is Name java:comp is not bound in this Context.
>>
>> Can anyone tell me why this is happening? What I don't understand is how
>> I
>> can successfully get a connection from within my ApplicationInitialiser
>> class and cannot get an connetion within an action.
>>
>> The complete clas listing is below.
>>
>> /**
>> *
>> */
>> package com.lagan.ini.thinclient.usermanagement;
>>
>> import java.io.IOException;
>> import java.io.InputStream;
>> import java.util.Properties;
>>
>> import javax.naming.Context;
>> import javax.naming.InitialContext;
>> import javax.naming.NamingException;
>> import javax.sql.DataSource;
>>
>> import org.apache.log4j.Logger;
>>
>> import com.lagan.ini.frontlinedata.IConstants;
>> import com.lagan.ini.frontlinedata.dao.DAOException;
>> import com.lagan.ini.frontlinedata.dao.IDAOFactory;
>> import com.lagan.ini.frontlinedata.dao.IDao;
>> import com.lagan.ini.frontlinedata.dao.IDivisionDAO;
>> import com.lagan.ini.frontlinedata.dao.IJobTitleDAO;
>> import com.lagan.ini.frontlinedata.dao.ITeamDAO;
>> import com.lagan.ini.frontlinedata.dao.IUserDAO;
>> import com.lagan.ini.frontlinedata.dao.IUserInfoDAO;
>> import com.lagan.ini.frontlinedata.jdbcdao.JDBCDaoFactory;
>>
>> /**
>> * @(protected) SeanMcE
>> *
>> */
>> public class DAOHelper
>> {
>>
>> //-- ---- ---- ---- ---- ---- ---- ---- ---- -----
>> //Private Members
>> //-- ---- ---- ---- ---- ---- ---- ---- ---- -----
>>
>> private static Logger logger = Logger.getLogger(DAOHelper.class);
>>
>> private static final ThreadLocal<IDAOFactory> threadDaoFactory
>> = new ThreadLocal<IDAOFactory>();
>>
>> //-- ---- ---- ---- ---- ---- ---- ---- ---- -----
>> //Constructors
>> //-- ---- ---- ---- ---- ---- ---- ---- ---- -----
>> /**
>> *
>> */
>> public DAOHelper()
>> {
>> }
>>
>> //-- ---- ---- ---- ---- ---- ---- ---- ---- -----
>> //Public Methods
>> //-- ---- ---- ---- ---- ---- ---- ---- ---- -----
>>
>> public static IUserDAO getUserDAO() throws DAOException
>> {
>> return getDAOFactory().getUserDAO();
>> }
>>
>> public static IUserInfoDAO getUserInfoDAO() throws DAOException
>> {
>> return getDAOFactory().getUserInfoDAO();
>> }
>>
>> public static ITeamDAO getTeamDAO() throws DAOException
>> {
>> return getDAOFactory().getTeamDAO();
>> }
>>
>> public static IDivisionDAO getDivisionDAO() throws DAOException
>> {
>> return getDAOFactory().getDivsionDAO();
>> }
>>
>> public static IJobTitleDAO getJobTitleDAO() throws DAOException
>> {
>> return getDAOFactory().getJobTitleDAO();
>> }
>>
>> public static IDAOFactory getDAOFactory() throws DAOException
>> {
>> IDAOFactory daoFactory = getThreadDaoFactory().get();
>>
>> if(daoFactory == null)
>> {
>> daoFactory = createDaoFactory();
>> getThreadDaoFactory().set(daoFactory);
>> }
>>
>> return daoFactory;
>> }
>>
>> public static void closeDAOConnection(IDao dao)
>> {
>> if(dao != null)
>> {
>> dao.close();
>> }
>> }
>> //-- ---- ---- ---- ---- ---- ---- ---- ---- -----
>> //Protected Methods
>> //-- ---- ---- ---- ---- ---- ---- ---- ---- -----
>>
>> //-- ---- ---- ---- ---- ---- ---- ---- ---- -----
>> //Private Methods
>> //-- ---- ---- ---- ---- ---- ---- ---- ---- -----
>>
>> private static ThreadLocal<IDAOFactory> getThreadDaoFactory()
>> {
>> return threadDaoFactory;
>> }
>>
>> private static IDAOFactory createDaoFactory() throws DAOException
>> {
>> logger.debug(IConstants.ENTERING);
>>
>> IDAOFactory daoFactory = null;
>>
>> if(IConstants.JDBC_DAO_FACTORY.equals(getDaoFactory()))
>> {
>> daoFactory = new JDBCDaoFactory(getDataSource());
>> }
>>
>> logger.debug(IConstants.EXITING);
>> return daoFactory;
>> }
>>
>> private static DataSource getDataSource() throws DAOException
>> {
>> logger.debug(IConstants.ENTERING);
>> DataSource dataSource = null;
>>
>> try
>> {
>> Context initCtx = new InitialContext();
>> Context envCtx = (Context) initCtx.lookup("java:comp/env");
>>
>> //Look up our data source
>> dataSource = (DataSource)envCtx.lookup("jdbc/Frontline");
>>
>> logger.debug("DataSource retrieved successfully");
>> }
>> catch (NamingException e)
>> {
>> String errorMessage = IConstants.DATA_SOURCE_ERROR + " using context
>> jdbc/Frontline";
>> logger.error(errorMessage);
>> logger.error(e.getMessage(),e);
>> throw new DAOException(errorMessage,e);
>> }
>>
>> logger.debug(IConstants.EXITING);
>> return dataSource;
>> }
>>
>> private static String getDaoFactory() throws DAOException
>> {
>> logger.debug(IConstants.ENTERING);
>>
>> InputStream daoPropertiesIs = Thread
>> .currentThread()
>> .getContextClassLoader()
>> .getResourceAsStream(IConstants.DAO_PROPERTIES);
>>
>> Properties daoProperties = new Properties();
>> try
>> {
>> daoProperties.load(daoPropertiesIs);
>> }
>> catch (IOException e)
>> {
>> new DAOException(e);
>> }
>> finally
>> {
>> closeInputStream(daoPropertiesIs);
>> }
>>
>> logger.debug(IConstants.EXITING);
>> return daoProperties.getProperty(IConstants.DAO_FACTORY_TYPE);
>> }
>>
>> private static void closeInputStream(InputStream is)
>> {
>> if(is != null)
>> {
>> try
>> {
>> is.close();
>> logger.debug("Properties file closed successfully");
>> }
>> catch (IOException e)
>> {
>> logger.error("Error closing Properties File: " + e.getMessage());
>> }
>> }
>> }
>> }
>>
>> --
>> View this message in context:
>> http://www.nabble.com/Struts-and-JNDI-tf4372040.html#a12461293
>> Sent from the Struts - User mailing list archive at Nabble.com.
>>
>>
>> -- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ------
>> To unsubscribe, e-mail: user-unsubscribe@(protected)
>> For additional commands, e-mail: user-help@(protected)
>
>>
>
>
>
> - Ray Clough
> ray@(protected)
>
>
>
> -- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ------
> To unsubscribe, e-mail: user-unsubscribe@(protected)
> For additional commands, e-mail: user-help@(protected)
>
>
>
--
View this message in context: http://www.nabble.com/Struts-and-JNDI-tf4372040
.html#a12474603
Sent from the Struts - User mailing list archive at Nabble.com.
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