Rajasekar Elango

I have following in my resin.conf file to enable logging:

<log name='' level='info' path='stdout:' timestamp='[%Y/%m/%d %H:%M:%S.%s] '/>

Now, I want to enable debug for a application class for brief period without restarting the app... I tried to set log level to fine with jconsole, but it doesn't log fine messages... it works if I change level to debug in resin.conf and restart the application, but no on the fly...

Is there a way to achieve this..?

Thank you,
Raja.

This blog might help you..

- Rajasekar
[ December 10, 2007: Message edited by: Rajasekar Elango ]

We need to invoke a class during weblogic startup that is part of application deployment jar...

It works if startup class is added to server classpath ( Weblogic documentation also insists that). But our startup class uses application logic and needs to be part of application jar..

We are getting java.lang.ClassNotFoundException for the class during start up. setting LoadBeforeAppDeployments to false also does not help...

Is there any other way to invoke a application class during weblogic startup...?

Any help would be appreciated.

I am developing J2SE Application with Hibernate and HSQL database and I want db schema to be created programatically.

I following EJB3 - JPA approach and using persistence.xml as show below.

<persistence xmlns="http://java.sun.com/xml/ns/persistence" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/persistence <a href="http://java.sun.com/xml/ns/persistence/persistence_1_0.xsd"" target="_blank" rel="nofollow">http://java.sun.com/xml/ns/persistence/persistence_1_0.xsd"</a> version="1.0"> <persistence-unit name="astrosoft" transaction-type="RESOURCE_LOCAL"> <provider>org.hibernate.ejb.HibernatePersistence</provider> <properties> <!-- Scan for annotated classes and Hibernate mapping XML files --> <property name="hibernate.archive.autodetection" value="class, hbm"/> <!-- SQL stdout logging --> <property name="hibernate.show_sql" value="true"/> <property name="hibernate.format_sql" value="true"/> <property name="use_sql_comments" value="true"/> <property name="hibernate.connection.driver_class" value="org.hsqldb.jdbcDriver"/> <property name="hibernate.connection.url" value="jdbc:hsqldb:file :mrgreen: b/astrodb;hsqldb.default_table_type=cached"/> <!-- <property name="hibernate.connection.url" value="jdbc:hsqldb:hsql://localhost"/> --> <property name="hibernate.connection.username" value="sa"/> <property name="hibernate.connection.shutdown" value="true"/> <property name="hibernate.c3p0.min_size" value="5"/> <property name="hibernate.c3p0.max_size" value="20"/> <property name="hibernate.c3p0.timeout" value="300"/> <property name="hibernate.c3p0.max_statements" value="50"/> <property name="hibernate.c3p0.idle_test_period" value="3000"/> <property name="hibernate.dialect" value="org.hibernate.dialect.HSQLDialect"/> <!-- <property name="hibernate.hbm2ddl.auto" value="create" /> --> </properties> </persistence-unit> </persistence>

To Use SchemaExport API, I need hibernate configuration, so I am trying to get hibernate cfg out of EJB 3 configuration. This is what I tried..

Ejb3Configuration cfg = new Ejb3Configuration().configure("/META-INF/persistence.xml"); Configuration hbmcfg = cfg.getHibernateConfiguration(); SchemaExport schemaExport = new SchemaExport(hbmcfg); schemaExport.create(true, true);

SEVERE: Error parsing XML: /META-INF/persistence.xml(1) Document is invalid: no grammar found.

Please help me in knowing right way of exporting schema using EJB3/hibernate. My basic requirement is tables to be created automatically only if they does not exist, Please let me know if there are better way of doing it...


Any help would be very much appreciated..

Thanks,
Raja.

Hi Andrew,

Which database are you using..? For informix, you can do something like this.
PreparedStatement ps; ... ... ps.execute(); Long id =((IfmxStatement)ps).getSerial();

Check your jdbc provider API, there might be something similar to this. Since this is database dependent, it is not part of standard JDBC API and beware you will lose portability if you use this.

Thanks,
Raja

Hi..

Check your PM,

Regards,
Raja.

You could enclose your code in try block and simply ignore the exception in catch block..

But catching ignoring exception is generally a bad practice as it conceals the problem..

-- Raja

Sum of Elements in array = 2 * Sum of all numbers until n + odd numer

odd number = (sum of all elements in array) - n*(n+1)

Thanks,
Raja

Hi,

I would like to share my java application packed as jnlp application.
I tried to host it in free web hosting sites like geocities, tripod, bravenet. But none of them seem to regonize jnlp extn and automatically open with javawebstart.

Are there any free java application hosting sites (while allows to host jnlp applications) available..?

Thanks a lot,
Raja.

Hi,

We have developed a ServiceLocator to cache home interfaces for all services.

Here is code for getRemoteHome

public EJBHome getRemoteHome(String jndiHomeName, Class className) throws ServiceLocatorException { EJBHome home = null; try { if (cache.containsKey(jndiHomeName)) { home = (EJBHome) cache.get(jndiHomeName); } else { Object objref = clusterInitialContext.lookup(jndiHomeName); Object obj = PortableRemoteObject.narrow(objref, className); home = (EJBHome) obj; cache.put(jndiHomeName, home); } } catch (NamingException ne) { throw new ServiceLocatorException(ne, "NamingException caught getting home name: " + jndiHomeName + " - ClassName: " + className.getName()+" local"+localURL+" and remote "+remoteURL, this.getClass()); } catch (Exception e) { throw new ServiceLocatorException(e, "Exception caught getting home name: " + jndiHomeName + " - ClassName: " + className.getName()+" local"+localURL+" and remote "+remoteURL, this.getClass()); } log.info("Returning home for " + jndiHomeName + " -> " + home); return home; }

This ServiceLocator is packed into a jar file and added to class path of 2 web applications.
It works fine if it is called by single web app. But when other web app calls getRemoteHome(), it finds ref in cache, it prints valid value in log, but it value null after getRemoteHome() call in other web app.

What could be problem..? What is the best design to implement ServiceLocator to be used between different webapplications..?

Any Suggestion/Advice would be of great help..

Thanks,
Raja.

Verify if you have packages and class in your class path.
You can use echo $CLASSPATH in unix or echo %CLASSPATH%.

If you are in jar file should be in classpath.

Thanks,
Raja

I use jarclassfinder . It is very good and has plugin for eclipse.

Raja

when I started preparing for SCJP..

Thanks,
Raja.

Completely Agree..once your gross exceeds 5 lakh p.a, take home gets reduced a lot... recently I got some 10% hike in sal, but got only 5% increase in take home, rest went to PF and tax

Thanks,
Raja

If you want to catch "StackOverflowError" , you have to catch "StackOverflowError" "Error" or "Throwable".
"Throwable" is the root of exception hierarchy and "Error" and "Exception" are subclasses of "Throwable" and "Exception" cannot catch "Error"

Regards,
E. Rajasekar.