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Posted to users@tomcat.apache.org by S B <sb...@gmail.com> on 2011/12/20 12:02:10 UTC
MBean InitialContext() Tomcat query- pls help
Hi,
I created and deployed an MBean in my tomcat. It uses datasource to connect
to DB.
My questions is:
When I create InitialContext() inside MBean's constructor and pass the
envContext to DBManager class to lookup datasource it works fine. However
when I create InitialContext() in DBManager class, it fails.
Is it necessary to create InitialContext() during loading of MBean (either
in ContextListener class or inside MBean constructor).
When I did new InitialContext() in my DBManager class which is called from
hello method of MBean it failed with below exception:
avax.naming.NoInitialContextException: Cannot instantiate class:
org.apache.naming.java.javaURLContextFactory [Root exception is
java.lang.ClassNotFoundException:
org.apache.naming.java.javaURLContextFactory]
I invoked hello method of MBean from JConsole.
Please let me know is it Tomcat specific? or same behavior is seen across
all app servers. Also, What difference does it make if I create
InitialContext inside MBean's constructor or in some other class at a later
point of time.
Thanks
Ravi
Re: MBean InitialContext() Tomcat query- pls help
Posted by Pid <pi...@pidster.com>.
On 20/12/2011 11:29, S B wrote:
> Hi,
> I am using :
>
> Server version: Apache Tomcat/6.0.32
> OS Name: Mac OS X
> OS Version: 10.6.8
> Architecture: x86_64
> JVM Version: 1.6.0_29-b11-402-10M3527
>
> Thanks,
> Ravi
Please post replies below the question, so the conversation order is
easily readable.
Please answer the other question below.
> On Tue, Dec 20, 2011 at 4:52 PM, Pid * <pi...@pidster.com> wrote:
>
>> On 20 Dec 2011, at 11:02, S B <sb...@gmail.com> wrote:
>>
>>> Hi,
>>>
>>> I created and deployed an MBean in my tomcat. It uses datasource to
>> connect
>>> to DB.
>>
>> Which version of Java? Tomcat?
>>
>>
>>> My questions is:
>>>
>>> When I create InitialContext() inside MBean's constructor and pass the
>>> envContext to DBManager class to lookup datasource it works fine. However
>>> when I create InitialContext() in DBManager class, it fails.
>>>
>>> Is it necessary to create InitialContext() during loading of MBean
>> (either
>>> in ContextListener class or inside MBean constructor).
>>
>> It depends on where you run the code. You haven't told us this.
>>
>> Can you post a code example.
As above, where are you putting your code?
p
>>> When I did new InitialContext() in my DBManager class which is called
>> from
>>> hello method of MBean it failed with below exception:
>>>
>>> avax.naming.NoInitialContextException: Cannot instantiate class:
>>> org.apache.naming.java.javaURLContextFactory [Root exception is
>>> java.lang.ClassNotFoundException:
>>> org.apache.naming.java.javaURLContextFactory]
>>>
>>> I invoked hello method of MBean from JConsole.
>>>
>>>
>>> Please let me know is it Tomcat specific? or same behavior is seen across
>>> all app servers. Also, What difference does it make if I create
>>> InitialContext inside MBean's constructor or in some other class at a
>> later
>>> point of time.
>>>
>>> Thanks
>>> Ravi
>>
>> ---------------------------------------------------------------------
>> To unsubscribe, e-mail: users-unsubscribe@tomcat.apache.org
>> For additional commands, e-mail: users-help@tomcat.apache.org
>>
>>
>
--
[key:62590808]
Re: MBean InitialContext() Tomcat query- pls help
Posted by S B <sb...@gmail.com>.
On Wed, Dec 21, 2011 at 12:09 AM, Pid * <pi...@pidster.com> wrote:
> On 20 Dec 2011, at 15:47, S B <sb...@gmail.com> wrote:
>
> > On Tue, Dec 20, 2011 at 7:00 PM, Pid <pi...@pidster.com> wrote:
> >
> >> On 20/12/2011 11:57, S B wrote:
> >>> MBeanImpl code is packaged as a war and deployed in tomcat along with
> >> it's
> >>> mbeans-descriptor.xml
> >>> I am not using ServletContextListener in my code. (mbean registration
> is
> >>> done inside constructor).
> >>
> >> Right, but what is calling the constructor?
> >>
> >
> > constructor is run during server startup hook. MBean is registered during
> > that time .
>
> This is like pulling teeth. What exactly is the "server startup hook"?
>
>
> > Mbean is registered using below code (in constructor):
> >
> > MBeanServer server = getServer();
> > server.registerMBean(*this*, new
> > ObjectName(StoreServerSyncAndReloadConstants.MBEAN_NAME)
> >
> > When we invoke reload() from jconsole, it causes class to load and call
>
> How can it do that if it needs to be loaded already for the MBean to work?
>
> How are you unloading it?
>
> > it's public constructor and create instance before calling reload() on
> that
> > instance.
>
> Right. I can't make any sense out of the above.
>
>
> > During reload() constructor is called again and registration code runs
> > again.
>
> So you re-register the Mbean that you're using to load the same MBean?
>
>
> p
>
Sorry about the confusion. I'll try to put in a more clear way. Here is the
complete flow from beginning.
There is a *ConfiguratorLoadingServlet* which loads and initializes on
tomcat startup. *<load-on-startup>* in *web.xml* causes that to happen.
In *init()* method of *ConfiguratorLoadingServlet* it does new *MBeanImpl()
*which causes mbean registration code inside its constructor to run.
After that in same *init() *method it calls *DBManager.reload()* which
causes config properties to load from db during startup.
DBManager.reload() code is like this:
{
InitialContext initContext = new InitialContext();
Context context = (Context) initContext.lookup("java:comp/env");
BasicDataSource ds = (BasicDataSource) context.lookup("jdbc/" +
dataSourceName);
// use ds to connect to db and get records.
}
MBeanImpl constructor code is like this:
public MBeanImpl() {
try {
MBeanServer server = getServer();
server.registerMBean(this, new
ObjectName(StoreServerSyncAndReloadConstants.MBEAN_NAME));
} catch (Exception e) {
logger.error("Error in Rgistering the Configurator MBean",e);
logger.warn("Configurator is NOT Available through JMX");
}
}
in destroy() method of *ConfiguratorLoadingServlet* it does the
unregisterMBean.
*Above flow works fine during tomcat startup. records are loaded
successfully. *
*Problem shows up when I invoke reload() from jconsole gui.*
Here is the flow that fails.
click reload() on jconsole gui.
it causes constructor of MBeanImpl to run. (verified from logs.)
calls reload() defined in MBeanImpl.
calls DBManager.reload()
inside DBManager.reload() it fails at InitialContext initContext = new
InitialContext();
the exception is - javax.naming.NoInitialContextException: Cannot
instantiate class: org.apache.naming.java.javaURLContextFactory [Root
exception is java.lang.ClassNotFoundException:
org.apache.naming.java.javaURLContextFactory]
*Workaround : *
I modified MBeanImpl() constructor like this:
private Context envContext = null;
public MBeanImpl() {
InitialContext initialContext;
try {
initialContext = new InitialContext();
envContext = (Context) initialContext.lookup("java:/comp/env");
} catch (NamingException e1) {
e1.printStackTrace();
}
try {
MBeanServer server = getServer();
server.registerMBean(this, new
ObjectName(StoreServerSyncAndReloadConstants.MBEAN_NAME));
} catch (Exception e) {
logger.error("Error in Rgistering the Configurator MBean",e);
logger.warn("Configurator is NOT Available through JMX");
}
}
Passed envContext as a parameter to DBManager(envContext)
Modified DBManager code looks like this :
DBManager.reload(Context envContext)
{
BasicDataSource ds = (BasicDataSource) envContext.lookup("jdbc/" +
dataSourceName);
// use ds to connect to db and get records.
}
Now if I invoke reload() from jconsole it works fine. The flow goes as
follows:
click reload() on jconsole gui
causes constructor of MBeanImpl to run where it does new InitialContext()
invokes reload() where it passes envContext object as parameter to
DBManager.reload(envContext)
DBManager uses passed in object to lookup datasource
flow completes with success.
*My question is : when I invoked reload() from jconsole , why it failed
when it tried to create new InitialContext() in DBManager. But when same
reload() is invoked during tomcat startup it succeeds.
Another question: Is there a better workaround to this problem?*
>
> >
> >
> >
> >
> >
> >
> >>
> >>> (I am using gmail and hitting reply button on your messages. Please let
> >> me
> >>> know if my messages are not being put in order as mailing list
> expects.)
> >>
> >> That shouldn't prevent you from scrolling down and entering your replies
> >> at the appropriate points in the text. Just like I am.
> >>
> >>
> >> p
> >>
> >>> On Tue, Dec 20, 2011 at 5:18 PM, Pid <pi...@pidster.com> wrote:
> >>>
> >>>> On 20/12/2011 11:46, S B wrote:
> >>>>> Code Sample that fails with exception(I am invoking reload() from
> >>>> jconsole
> >>>>> ):
> >>>>>
> >>>>> class MBeanImpl implements MBeanInterface{
> >>>>>
> >>>>> public MBeanImpl{
> >>>>> // code to register this bean.
> >>>>> }
> >>>>>
> >>>>>
> >>>>> @Override
> >>>>> public void reload() {
> >>>>>
> >>>>> DBManager.loadFromDB();
> >>>>>
> >>>>> }
> >>>>> }
> >>>>>
> >>>>>
> >>>>> class DBManager{
> >>>>>
> >>>>> public static void loadFromDB(){
> >>>>>
> >>>>> InitialContext initContext = new
> >>>>> InitialContext(); // here it fails with
> >> exception
> >>>>> avax.naming.NoInitialContextException: Cannot instantiate class:
> >>>>> org.apache.naming.java.javaURLContextFactory [Root
> >>>>>
> >>>>> // exception is java.lang.ClassNotFoundException:
> >>>>> org.apache.naming.java.javaURLContextFactory]
> >>>>> Context context = (Context)
> >>>>> initContext.lookup("java:comp/env");
> >>>>> logger.info("context found " + context);
> >>>>> BasicDataSource ds = (BasicDataSource)
> >>>>> context.lookup("jdbc/" + dataSourceName);
> >>>>> ...............
> >>>>> ...............
> >>>>> }
> >>>>>
> >>>>> }
> >>>>>
> >>>>>
> >>>>> ---------------------------------------------
> >>>>>
> >>>>> Code Sample that works:
> >>>>>
> >>>>> class MBeanImpl implements MBeanInterface{
> >>>>> private Context envContext = null;
> >>>>>
> >>>>> public MBeanImpl{
> >>>>> InitialContext initialContext = new InitialContext();
> >>>>> envContext = (Context)
> >>>> initialContext.lookup("java:/comp/env");
> >>>>> // code to register this bean.
> >>>>> }
> >>>>>
> >>>>>
> >>>>> @Override
> >>>>> public void reload() {
> >>>>>
> >>>>> DBManager.loadFromDB(envContext); // passed context object
> >>>>> obtained in constructor
> >>>>>
> >>>>> }
> >>>>> }
> >>>>>
> >>>>>
> >>>>> class DBManager{
> >>>>>
> >>>>> public static void loadFromDB(Context context){
> >>>>>
> >>>>> BasicDataSource ds = (BasicDataSource)
> >>>>> context.lookup("jdbc/" + dataSourceName); // works fine as I am not
> >>>>> creating new InitialContext here.
> >>>>> ...............
> >>>>> ...............
> >>>>> }
> >>>>>
> >>>>> }
> >>>>
> >>>> Where does the MBeanImpl code run? In a ServletContextListener, or
> >>>> somewhere else?
> >>>>
> >>>>
> >>>> p
> >>>>
> >>>>
> >>>>> On Tue, Dec 20, 2011 at 4:59 PM, S B <sb...@gmail.com> wrote:
> >>>>>
> >>>>>> Hi,
> >>>>>> I am using :
> >>>>>>
> >>>>>> Server version: Apache Tomcat/6.0.32
> >>>>>> OS Name: Mac OS X
> >>>>>> OS Version: 10.6.8
> >>>>>> Architecture: x86_64
> >>>>>> JVM Version: 1.6.0_29-b11-402-10M3527
> >>>>>>
> >>>>>> Thanks,
> >>>>>> Ravi
> >>>>>>
> >>>>>>
> >>>>>> On Tue, Dec 20, 2011 at 4:52 PM, Pid * <pi...@pidster.com> wrote:
> >>>>>>
> >>>>>>> On 20 Dec 2011, at 11:02, S B <sb...@gmail.com> wrote:
> >>>>>>>
> >>>>>>>> Hi,
> >>>>>>>>
> >>>>>>>> I created and deployed an MBean in my tomcat. It uses datasource
> to
> >>>>>>> connect
> >>>>>>>> to DB.
> >>>>>>>
> >>>>>>> Which version of Java? Tomcat?
> >>>>>>>
> >>>>>>>
> >>>>>>>> My questions is:
> >>>>>>>>
> >>>>>>>> When I create InitialContext() inside MBean's constructor and pass
> >> the
> >>>>>>>> envContext to DBManager class to lookup datasource it works fine.
> >>>>>>> However
> >>>>>>>> when I create InitialContext() in DBManager class, it fails.
> >>>>>>>>
> >>>>>>>> Is it necessary to create InitialContext() during loading of MBean
> >>>>>>> (either
> >>>>>>>> in ContextListener class or inside MBean constructor).
> >>>>>>>
> >>>>>>> It depends on where you run the code. You haven't told us this.
> >>>>>>>
> >>>>>>> Can you post a code example.
> >>>>>>>
> >>>>>>>
> >>>>>>> p
> >>>>>>>
> >>>>>>>
> >>>>>>>> When I did new InitialContext() in my DBManager class which is
> >> called
> >>>>>>> from
> >>>>>>>> hello method of MBean it failed with below exception:
> >>>>>>>>
> >>>>>>>> avax.naming.NoInitialContextException: Cannot instantiate class:
> >>>>>>>> org.apache.naming.java.javaURLContextFactory [Root exception is
> >>>>>>>> java.lang.ClassNotFoundException:
> >>>>>>>> org.apache.naming.java.javaURLContextFactory]
> >>>>>>>>
> >>>>>>>> I invoked hello method of MBean from JConsole.
> >>>>>>>>
> >>>>>>>>
> >>>>>>>> Please let me know is it Tomcat specific? or same behavior is seen
> >>>>>>> across
> >>>>>>>> all app servers. Also, What difference does it make if I create
> >>>>>>>> InitialContext inside MBean's constructor or in some other class
> at
> >> a
> >>>>>>> later
> >>>>>>>> point of time.
> >>>>>>>>
> >>>>>>>> Thanks
> >>>>>>>> Ravi
> >>>>>>>
> >>>>>>>
> ---------------------------------------------------------------------
> >>>>>>> To unsubscribe, e-mail: users-unsubscribe@tomcat.apache.org
> >>>>>>> For additional commands, e-mail: users-help@tomcat.apache.org
> >>>>>>>
> >>>>>>>
> >>>>>>
> >>>>>
> >>>>
> >>>>
> >>>> --
> >>>>
> >>>> [key:62590808]
> >>>>
> >>>>
> >>>
> >>
> >>
> >> --
> >>
> >> [key:62590808]
> >>
> >>
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: users-unsubscribe@tomcat.apache.org
> For additional commands, e-mail: users-help@tomcat.apache.org
>
>
Re: MBean InitialContext() Tomcat query- pls help
Posted by Pid * <pi...@pidster.com>.
On 20 Dec 2011, at 15:47, S B <sb...@gmail.com> wrote:
> On Tue, Dec 20, 2011 at 7:00 PM, Pid <pi...@pidster.com> wrote:
>
>> On 20/12/2011 11:57, S B wrote:
>>> MBeanImpl code is packaged as a war and deployed in tomcat along with
>> it's
>>> mbeans-descriptor.xml
>>> I am not using ServletContextListener in my code. (mbean registration is
>>> done inside constructor).
>>
>> Right, but what is calling the constructor?
>>
>
> constructor is run during server startup hook. MBean is registered during
> that time .
This is like pulling teeth. What exactly is the "server startup hook"?
> Mbean is registered using below code (in constructor):
>
> MBeanServer server = getServer();
> server.registerMBean(*this*, new
> ObjectName(StoreServerSyncAndReloadConstants.MBEAN_NAME)
>
> When we invoke reload() from jconsole, it causes class to load and call
How can it do that if it needs to be loaded already for the MBean to work?
How are you unloading it?
> it's public constructor and create instance before calling reload() on that
> instance.
Right. I can't make any sense out of the above.
> During reload() constructor is called again and registration code runs
> again.
So you re-register the Mbean that you're using to load the same MBean?
p
>
>
>
>
>
>
>>
>>> (I am using gmail and hitting reply button on your messages. Please let
>> me
>>> know if my messages are not being put in order as mailing list expects.)
>>
>> That shouldn't prevent you from scrolling down and entering your replies
>> at the appropriate points in the text. Just like I am.
>>
>>
>> p
>>
>>> On Tue, Dec 20, 2011 at 5:18 PM, Pid <pi...@pidster.com> wrote:
>>>
>>>> On 20/12/2011 11:46, S B wrote:
>>>>> Code Sample that fails with exception(I am invoking reload() from
>>>> jconsole
>>>>> ):
>>>>>
>>>>> class MBeanImpl implements MBeanInterface{
>>>>>
>>>>> public MBeanImpl{
>>>>> // code to register this bean.
>>>>> }
>>>>>
>>>>>
>>>>> @Override
>>>>> public void reload() {
>>>>>
>>>>> DBManager.loadFromDB();
>>>>>
>>>>> }
>>>>> }
>>>>>
>>>>>
>>>>> class DBManager{
>>>>>
>>>>> public static void loadFromDB(){
>>>>>
>>>>> InitialContext initContext = new
>>>>> InitialContext(); // here it fails with
>> exception
>>>>> avax.naming.NoInitialContextException: Cannot instantiate class:
>>>>> org.apache.naming.java.javaURLContextFactory [Root
>>>>>
>>>>> // exception is java.lang.ClassNotFoundException:
>>>>> org.apache.naming.java.javaURLContextFactory]
>>>>> Context context = (Context)
>>>>> initContext.lookup("java:comp/env");
>>>>> logger.info("context found " + context);
>>>>> BasicDataSource ds = (BasicDataSource)
>>>>> context.lookup("jdbc/" + dataSourceName);
>>>>> ...............
>>>>> ...............
>>>>> }
>>>>>
>>>>> }
>>>>>
>>>>>
>>>>> ---------------------------------------------
>>>>>
>>>>> Code Sample that works:
>>>>>
>>>>> class MBeanImpl implements MBeanInterface{
>>>>> private Context envContext = null;
>>>>>
>>>>> public MBeanImpl{
>>>>> InitialContext initialContext = new InitialContext();
>>>>> envContext = (Context)
>>>> initialContext.lookup("java:/comp/env");
>>>>> // code to register this bean.
>>>>> }
>>>>>
>>>>>
>>>>> @Override
>>>>> public void reload() {
>>>>>
>>>>> DBManager.loadFromDB(envContext); // passed context object
>>>>> obtained in constructor
>>>>>
>>>>> }
>>>>> }
>>>>>
>>>>>
>>>>> class DBManager{
>>>>>
>>>>> public static void loadFromDB(Context context){
>>>>>
>>>>> BasicDataSource ds = (BasicDataSource)
>>>>> context.lookup("jdbc/" + dataSourceName); // works fine as I am not
>>>>> creating new InitialContext here.
>>>>> ...............
>>>>> ...............
>>>>> }
>>>>>
>>>>> }
>>>>
>>>> Where does the MBeanImpl code run? In a ServletContextListener, or
>>>> somewhere else?
>>>>
>>>>
>>>> p
>>>>
>>>>
>>>>> On Tue, Dec 20, 2011 at 4:59 PM, S B <sb...@gmail.com> wrote:
>>>>>
>>>>>> Hi,
>>>>>> I am using :
>>>>>>
>>>>>> Server version: Apache Tomcat/6.0.32
>>>>>> OS Name: Mac OS X
>>>>>> OS Version: 10.6.8
>>>>>> Architecture: x86_64
>>>>>> JVM Version: 1.6.0_29-b11-402-10M3527
>>>>>>
>>>>>> Thanks,
>>>>>> Ravi
>>>>>>
>>>>>>
>>>>>> On Tue, Dec 20, 2011 at 4:52 PM, Pid * <pi...@pidster.com> wrote:
>>>>>>
>>>>>>> On 20 Dec 2011, at 11:02, S B <sb...@gmail.com> wrote:
>>>>>>>
>>>>>>>> Hi,
>>>>>>>>
>>>>>>>> I created and deployed an MBean in my tomcat. It uses datasource to
>>>>>>> connect
>>>>>>>> to DB.
>>>>>>>
>>>>>>> Which version of Java? Tomcat?
>>>>>>>
>>>>>>>
>>>>>>>> My questions is:
>>>>>>>>
>>>>>>>> When I create InitialContext() inside MBean's constructor and pass
>> the
>>>>>>>> envContext to DBManager class to lookup datasource it works fine.
>>>>>>> However
>>>>>>>> when I create InitialContext() in DBManager class, it fails.
>>>>>>>>
>>>>>>>> Is it necessary to create InitialContext() during loading of MBean
>>>>>>> (either
>>>>>>>> in ContextListener class or inside MBean constructor).
>>>>>>>
>>>>>>> It depends on where you run the code. You haven't told us this.
>>>>>>>
>>>>>>> Can you post a code example.
>>>>>>>
>>>>>>>
>>>>>>> p
>>>>>>>
>>>>>>>
>>>>>>>> When I did new InitialContext() in my DBManager class which is
>> called
>>>>>>> from
>>>>>>>> hello method of MBean it failed with below exception:
>>>>>>>>
>>>>>>>> avax.naming.NoInitialContextException: Cannot instantiate class:
>>>>>>>> org.apache.naming.java.javaURLContextFactory [Root exception is
>>>>>>>> java.lang.ClassNotFoundException:
>>>>>>>> org.apache.naming.java.javaURLContextFactory]
>>>>>>>>
>>>>>>>> I invoked hello method of MBean from JConsole.
>>>>>>>>
>>>>>>>>
>>>>>>>> Please let me know is it Tomcat specific? or same behavior is seen
>>>>>>> across
>>>>>>>> all app servers. Also, What difference does it make if I create
>>>>>>>> InitialContext inside MBean's constructor or in some other class at
>> a
>>>>>>> later
>>>>>>>> point of time.
>>>>>>>>
>>>>>>>> Thanks
>>>>>>>> Ravi
>>>>>>>
>>>>>>> ---------------------------------------------------------------------
>>>>>>> To unsubscribe, e-mail: users-unsubscribe@tomcat.apache.org
>>>>>>> For additional commands, e-mail: users-help@tomcat.apache.org
>>>>>>>
>>>>>>>
>>>>>>
>>>>>
>>>>
>>>>
>>>> --
>>>>
>>>> [key:62590808]
>>>>
>>>>
>>>
>>
>>
>> --
>>
>> [key:62590808]
>>
>>
---------------------------------------------------------------------
To unsubscribe, e-mail: users-unsubscribe@tomcat.apache.org
For additional commands, e-mail: users-help@tomcat.apache.org
Re: MBean InitialContext() Tomcat query- pls help
Posted by S B <sb...@gmail.com>.
On Tue, Dec 20, 2011 at 7:00 PM, Pid <pi...@pidster.com> wrote:
> On 20/12/2011 11:57, S B wrote:
> > MBeanImpl code is packaged as a war and deployed in tomcat along with
> it's
> > mbeans-descriptor.xml
> > I am not using ServletContextListener in my code. (mbean registration is
> > done inside constructor).
>
> Right, but what is calling the constructor?
>
constructor is run during server startup hook. MBean is registered during
that time .
MBean is registered using below code (in constructor):
MBeanServer server = getServer();
server.registerMBean(*this*, new
ObjectName(StoreServerSyncAndReloadConstants.MBEAN_NAME)
When we invoke reload() from jconsole, it causes class to load and call
it's public constructor and create instance before calling reload() on that
instance.
During reload() constructor is called again and registration code runs
again.
>
> > (I am using gmail and hitting reply button on your messages. Please let
> me
> > know if my messages are not being put in order as mailing list expects.)
>
> That shouldn't prevent you from scrolling down and entering your replies
> at the appropriate points in the text. Just like I am.
>
>
> p
>
> > On Tue, Dec 20, 2011 at 5:18 PM, Pid <pi...@pidster.com> wrote:
> >
> >> On 20/12/2011 11:46, S B wrote:
> >>> Code Sample that fails with exception(I am invoking reload() from
> >> jconsole
> >>> ):
> >>>
> >>> class MBeanImpl implements MBeanInterface{
> >>>
> >>> public MBeanImpl{
> >>> // code to register this bean.
> >>> }
> >>>
> >>>
> >>> @Override
> >>> public void reload() {
> >>>
> >>> DBManager.loadFromDB();
> >>>
> >>> }
> >>> }
> >>>
> >>>
> >>> class DBManager{
> >>>
> >>> public static void loadFromDB(){
> >>>
> >>> InitialContext initContext = new
> >>> InitialContext(); // here it fails with
> exception
> >>> avax.naming.NoInitialContextException: Cannot instantiate class:
> >>> org.apache.naming.java.javaURLContextFactory [Root
> >>>
> >>> // exception is java.lang.ClassNotFoundException:
> >>> org.apache.naming.java.javaURLContextFactory]
> >>> Context context = (Context)
> >>> initContext.lookup("java:comp/env");
> >>> logger.info("context found " + context);
> >>> BasicDataSource ds = (BasicDataSource)
> >>> context.lookup("jdbc/" + dataSourceName);
> >>> ...............
> >>> ...............
> >>> }
> >>>
> >>> }
> >>>
> >>>
> >>> ---------------------------------------------
> >>>
> >>> Code Sample that works:
> >>>
> >>> class MBeanImpl implements MBeanInterface{
> >>> private Context envContext = null;
> >>>
> >>> public MBeanImpl{
> >>> InitialContext initialContext = new InitialContext();
> >>> envContext = (Context)
> >> initialContext.lookup("java:/comp/env");
> >>> // code to register this bean.
> >>> }
> >>>
> >>>
> >>> @Override
> >>> public void reload() {
> >>>
> >>> DBManager.loadFromDB(envContext); // passed context object
> >>> obtained in constructor
> >>>
> >>> }
> >>> }
> >>>
> >>>
> >>> class DBManager{
> >>>
> >>> public static void loadFromDB(Context context){
> >>>
> >>> BasicDataSource ds = (BasicDataSource)
> >>> context.lookup("jdbc/" + dataSourceName); // works fine as I am not
> >>> creating new InitialContext here.
> >>> ...............
> >>> ...............
> >>> }
> >>>
> >>> }
> >>
> >> Where does the MBeanImpl code run? In a ServletContextListener, or
> >> somewhere else?
> >>
> >>
> >> p
> >>
> >>
> >>> On Tue, Dec 20, 2011 at 4:59 PM, S B <sb...@gmail.com> wrote:
> >>>
> >>>> Hi,
> >>>> I am using :
> >>>>
> >>>> Server version: Apache Tomcat/6.0.32
> >>>> OS Name: Mac OS X
> >>>> OS Version: 10.6.8
> >>>> Architecture: x86_64
> >>>> JVM Version: 1.6.0_29-b11-402-10M3527
> >>>>
> >>>> Thanks,
> >>>> Ravi
> >>>>
> >>>>
> >>>> On Tue, Dec 20, 2011 at 4:52 PM, Pid * <pi...@pidster.com> wrote:
> >>>>
> >>>>> On 20 Dec 2011, at 11:02, S B <sb...@gmail.com> wrote:
> >>>>>
> >>>>>> Hi,
> >>>>>>
> >>>>>> I created and deployed an MBean in my tomcat. It uses datasource to
> >>>>> connect
> >>>>>> to DB.
> >>>>>
> >>>>> Which version of Java? Tomcat?
> >>>>>
> >>>>>
> >>>>>> My questions is:
> >>>>>>
> >>>>>> When I create InitialContext() inside MBean's constructor and pass
> the
> >>>>>> envContext to DBManager class to lookup datasource it works fine.
> >>>>> However
> >>>>>> when I create InitialContext() in DBManager class, it fails.
> >>>>>>
> >>>>>> Is it necessary to create InitialContext() during loading of MBean
> >>>>> (either
> >>>>>> in ContextListener class or inside MBean constructor).
> >>>>>
> >>>>> It depends on where you run the code. You haven't told us this.
> >>>>>
> >>>>> Can you post a code example.
> >>>>>
> >>>>>
> >>>>> p
> >>>>>
> >>>>>
> >>>>>> When I did new InitialContext() in my DBManager class which is
> called
> >>>>> from
> >>>>>> hello method of MBean it failed with below exception:
> >>>>>>
> >>>>>> avax.naming.NoInitialContextException: Cannot instantiate class:
> >>>>>> org.apache.naming.java.javaURLContextFactory [Root exception is
> >>>>>> java.lang.ClassNotFoundException:
> >>>>>> org.apache.naming.java.javaURLContextFactory]
> >>>>>>
> >>>>>> I invoked hello method of MBean from JConsole.
> >>>>>>
> >>>>>>
> >>>>>> Please let me know is it Tomcat specific? or same behavior is seen
> >>>>> across
> >>>>>> all app servers. Also, What difference does it make if I create
> >>>>>> InitialContext inside MBean's constructor or in some other class at
> a
> >>>>> later
> >>>>>> point of time.
> >>>>>>
> >>>>>> Thanks
> >>>>>> Ravi
> >>>>>
> >>>>> ---------------------------------------------------------------------
> >>>>> To unsubscribe, e-mail: users-unsubscribe@tomcat.apache.org
> >>>>> For additional commands, e-mail: users-help@tomcat.apache.org
> >>>>>
> >>>>>
> >>>>
> >>>
> >>
> >>
> >> --
> >>
> >> [key:62590808]
> >>
> >>
> >
>
>
> --
>
> [key:62590808]
>
>
Re: MBean InitialContext() Tomcat query- pls help
Posted by Pid <pi...@pidster.com>.
On 20/12/2011 11:57, S B wrote:
> MBeanImpl code is packaged as a war and deployed in tomcat along with it's
> mbeans-descriptor.xml
> I am not using ServletContextListener in my code. (mbean registration is
> done inside constructor).
Right, but what is calling the constructor?
> (I am using gmail and hitting reply button on your messages. Please let me
> know if my messages are not being put in order as mailing list expects.)
That shouldn't prevent you from scrolling down and entering your replies
at the appropriate points in the text. Just like I am.
p
> On Tue, Dec 20, 2011 at 5:18 PM, Pid <pi...@pidster.com> wrote:
>
>> On 20/12/2011 11:46, S B wrote:
>>> Code Sample that fails with exception(I am invoking reload() from
>> jconsole
>>> ):
>>>
>>> class MBeanImpl implements MBeanInterface{
>>>
>>> public MBeanImpl{
>>> // code to register this bean.
>>> }
>>>
>>>
>>> @Override
>>> public void reload() {
>>>
>>> DBManager.loadFromDB();
>>>
>>> }
>>> }
>>>
>>>
>>> class DBManager{
>>>
>>> public static void loadFromDB(){
>>>
>>> InitialContext initContext = new
>>> InitialContext(); // here it fails with exception
>>> avax.naming.NoInitialContextException: Cannot instantiate class:
>>> org.apache.naming.java.javaURLContextFactory [Root
>>>
>>> // exception is java.lang.ClassNotFoundException:
>>> org.apache.naming.java.javaURLContextFactory]
>>> Context context = (Context)
>>> initContext.lookup("java:comp/env");
>>> logger.info("context found " + context);
>>> BasicDataSource ds = (BasicDataSource)
>>> context.lookup("jdbc/" + dataSourceName);
>>> ...............
>>> ...............
>>> }
>>>
>>> }
>>>
>>>
>>> ---------------------------------------------
>>>
>>> Code Sample that works:
>>>
>>> class MBeanImpl implements MBeanInterface{
>>> private Context envContext = null;
>>>
>>> public MBeanImpl{
>>> InitialContext initialContext = new InitialContext();
>>> envContext = (Context)
>> initialContext.lookup("java:/comp/env");
>>> // code to register this bean.
>>> }
>>>
>>>
>>> @Override
>>> public void reload() {
>>>
>>> DBManager.loadFromDB(envContext); // passed context object
>>> obtained in constructor
>>>
>>> }
>>> }
>>>
>>>
>>> class DBManager{
>>>
>>> public static void loadFromDB(Context context){
>>>
>>> BasicDataSource ds = (BasicDataSource)
>>> context.lookup("jdbc/" + dataSourceName); // works fine as I am not
>>> creating new InitialContext here.
>>> ...............
>>> ...............
>>> }
>>>
>>> }
>>
>> Where does the MBeanImpl code run? In a ServletContextListener, or
>> somewhere else?
>>
>>
>> p
>>
>>
>>> On Tue, Dec 20, 2011 at 4:59 PM, S B <sb...@gmail.com> wrote:
>>>
>>>> Hi,
>>>> I am using :
>>>>
>>>> Server version: Apache Tomcat/6.0.32
>>>> OS Name: Mac OS X
>>>> OS Version: 10.6.8
>>>> Architecture: x86_64
>>>> JVM Version: 1.6.0_29-b11-402-10M3527
>>>>
>>>> Thanks,
>>>> Ravi
>>>>
>>>>
>>>> On Tue, Dec 20, 2011 at 4:52 PM, Pid * <pi...@pidster.com> wrote:
>>>>
>>>>> On 20 Dec 2011, at 11:02, S B <sb...@gmail.com> wrote:
>>>>>
>>>>>> Hi,
>>>>>>
>>>>>> I created and deployed an MBean in my tomcat. It uses datasource to
>>>>> connect
>>>>>> to DB.
>>>>>
>>>>> Which version of Java? Tomcat?
>>>>>
>>>>>
>>>>>> My questions is:
>>>>>>
>>>>>> When I create InitialContext() inside MBean's constructor and pass the
>>>>>> envContext to DBManager class to lookup datasource it works fine.
>>>>> However
>>>>>> when I create InitialContext() in DBManager class, it fails.
>>>>>>
>>>>>> Is it necessary to create InitialContext() during loading of MBean
>>>>> (either
>>>>>> in ContextListener class or inside MBean constructor).
>>>>>
>>>>> It depends on where you run the code. You haven't told us this.
>>>>>
>>>>> Can you post a code example.
>>>>>
>>>>>
>>>>> p
>>>>>
>>>>>
>>>>>> When I did new InitialContext() in my DBManager class which is called
>>>>> from
>>>>>> hello method of MBean it failed with below exception:
>>>>>>
>>>>>> avax.naming.NoInitialContextException: Cannot instantiate class:
>>>>>> org.apache.naming.java.javaURLContextFactory [Root exception is
>>>>>> java.lang.ClassNotFoundException:
>>>>>> org.apache.naming.java.javaURLContextFactory]
>>>>>>
>>>>>> I invoked hello method of MBean from JConsole.
>>>>>>
>>>>>>
>>>>>> Please let me know is it Tomcat specific? or same behavior is seen
>>>>> across
>>>>>> all app servers. Also, What difference does it make if I create
>>>>>> InitialContext inside MBean's constructor or in some other class at a
>>>>> later
>>>>>> point of time.
>>>>>>
>>>>>> Thanks
>>>>>> Ravi
>>>>>
>>>>> ---------------------------------------------------------------------
>>>>> To unsubscribe, e-mail: users-unsubscribe@tomcat.apache.org
>>>>> For additional commands, e-mail: users-help@tomcat.apache.org
>>>>>
>>>>>
>>>>
>>>
>>
>>
>> --
>>
>> [key:62590808]
>>
>>
>
--
[key:62590808]
Re: MBean InitialContext() Tomcat query- pls help
Posted by S B <sb...@gmail.com>.
MBeanImpl code is packaged as a war and deployed in tomcat along with it's
mbeans-descriptor.xml
I am not using ServletContextListener in my code. (mbean registration is
done inside constructor).
(I am using gmail and hitting reply button on your messages. Please let me
know if my messages are not being put in order as mailing list expects.)
On Tue, Dec 20, 2011 at 5:18 PM, Pid <pi...@pidster.com> wrote:
> On 20/12/2011 11:46, S B wrote:
> > Code Sample that fails with exception(I am invoking reload() from
> jconsole
> > ):
> >
> > class MBeanImpl implements MBeanInterface{
> >
> > public MBeanImpl{
> > // code to register this bean.
> > }
> >
> >
> > @Override
> > public void reload() {
> >
> > DBManager.loadFromDB();
> >
> > }
> > }
> >
> >
> > class DBManager{
> >
> > public static void loadFromDB(){
> >
> > InitialContext initContext = new
> > InitialContext(); // here it fails with exception
> > avax.naming.NoInitialContextException: Cannot instantiate class:
> > org.apache.naming.java.javaURLContextFactory [Root
> >
> > // exception is java.lang.ClassNotFoundException:
> > org.apache.naming.java.javaURLContextFactory]
> > Context context = (Context)
> > initContext.lookup("java:comp/env");
> > logger.info("context found " + context);
> > BasicDataSource ds = (BasicDataSource)
> > context.lookup("jdbc/" + dataSourceName);
> > ...............
> > ...............
> > }
> >
> > }
> >
> >
> > ---------------------------------------------
> >
> > Code Sample that works:
> >
> > class MBeanImpl implements MBeanInterface{
> > private Context envContext = null;
> >
> > public MBeanImpl{
> > InitialContext initialContext = new InitialContext();
> > envContext = (Context)
> initialContext.lookup("java:/comp/env");
> > // code to register this bean.
> > }
> >
> >
> > @Override
> > public void reload() {
> >
> > DBManager.loadFromDB(envContext); // passed context object
> > obtained in constructor
> >
> > }
> > }
> >
> >
> > class DBManager{
> >
> > public static void loadFromDB(Context context){
> >
> > BasicDataSource ds = (BasicDataSource)
> > context.lookup("jdbc/" + dataSourceName); // works fine as I am not
> > creating new InitialContext here.
> > ...............
> > ...............
> > }
> >
> > }
>
> Where does the MBeanImpl code run? In a ServletContextListener, or
> somewhere else?
>
>
> p
>
>
> > On Tue, Dec 20, 2011 at 4:59 PM, S B <sb...@gmail.com> wrote:
> >
> >> Hi,
> >> I am using :
> >>
> >> Server version: Apache Tomcat/6.0.32
> >> OS Name: Mac OS X
> >> OS Version: 10.6.8
> >> Architecture: x86_64
> >> JVM Version: 1.6.0_29-b11-402-10M3527
> >>
> >> Thanks,
> >> Ravi
> >>
> >>
> >> On Tue, Dec 20, 2011 at 4:52 PM, Pid * <pi...@pidster.com> wrote:
> >>
> >>> On 20 Dec 2011, at 11:02, S B <sb...@gmail.com> wrote:
> >>>
> >>>> Hi,
> >>>>
> >>>> I created and deployed an MBean in my tomcat. It uses datasource to
> >>> connect
> >>>> to DB.
> >>>
> >>> Which version of Java? Tomcat?
> >>>
> >>>
> >>>> My questions is:
> >>>>
> >>>> When I create InitialContext() inside MBean's constructor and pass the
> >>>> envContext to DBManager class to lookup datasource it works fine.
> >>> However
> >>>> when I create InitialContext() in DBManager class, it fails.
> >>>>
> >>>> Is it necessary to create InitialContext() during loading of MBean
> >>> (either
> >>>> in ContextListener class or inside MBean constructor).
> >>>
> >>> It depends on where you run the code. You haven't told us this.
> >>>
> >>> Can you post a code example.
> >>>
> >>>
> >>> p
> >>>
> >>>
> >>>> When I did new InitialContext() in my DBManager class which is called
> >>> from
> >>>> hello method of MBean it failed with below exception:
> >>>>
> >>>> avax.naming.NoInitialContextException: Cannot instantiate class:
> >>>> org.apache.naming.java.javaURLContextFactory [Root exception is
> >>>> java.lang.ClassNotFoundException:
> >>>> org.apache.naming.java.javaURLContextFactory]
> >>>>
> >>>> I invoked hello method of MBean from JConsole.
> >>>>
> >>>>
> >>>> Please let me know is it Tomcat specific? or same behavior is seen
> >>> across
> >>>> all app servers. Also, What difference does it make if I create
> >>>> InitialContext inside MBean's constructor or in some other class at a
> >>> later
> >>>> point of time.
> >>>>
> >>>> Thanks
> >>>> Ravi
> >>>
> >>> ---------------------------------------------------------------------
> >>> To unsubscribe, e-mail: users-unsubscribe@tomcat.apache.org
> >>> For additional commands, e-mail: users-help@tomcat.apache.org
> >>>
> >>>
> >>
> >
>
>
> --
>
> [key:62590808]
>
>
Re: MBean InitialContext() Tomcat query- pls help
Posted by Pid <pi...@pidster.com>.
On 20/12/2011 11:46, S B wrote:
> Code Sample that fails with exception(I am invoking reload() from jconsole
> ):
>
> class MBeanImpl implements MBeanInterface{
>
> public MBeanImpl{
> // code to register this bean.
> }
>
>
> @Override
> public void reload() {
>
> DBManager.loadFromDB();
>
> }
> }
>
>
> class DBManager{
>
> public static void loadFromDB(){
>
> InitialContext initContext = new
> InitialContext(); // here it fails with exception
> avax.naming.NoInitialContextException: Cannot instantiate class:
> org.apache.naming.java.javaURLContextFactory [Root
>
> // exception is java.lang.ClassNotFoundException:
> org.apache.naming.java.javaURLContextFactory]
> Context context = (Context)
> initContext.lookup("java:comp/env");
> logger.info("context found " + context);
> BasicDataSource ds = (BasicDataSource)
> context.lookup("jdbc/" + dataSourceName);
> ...............
> ...............
> }
>
> }
>
>
> ---------------------------------------------
>
> Code Sample that works:
>
> class MBeanImpl implements MBeanInterface{
> private Context envContext = null;
>
> public MBeanImpl{
> InitialContext initialContext = new InitialContext();
> envContext = (Context) initialContext.lookup("java:/comp/env");
> // code to register this bean.
> }
>
>
> @Override
> public void reload() {
>
> DBManager.loadFromDB(envContext); // passed context object
> obtained in constructor
>
> }
> }
>
>
> class DBManager{
>
> public static void loadFromDB(Context context){
>
> BasicDataSource ds = (BasicDataSource)
> context.lookup("jdbc/" + dataSourceName); // works fine as I am not
> creating new InitialContext here.
> ...............
> ...............
> }
>
> }
Where does the MBeanImpl code run? In a ServletContextListener, or
somewhere else?
p
> On Tue, Dec 20, 2011 at 4:59 PM, S B <sb...@gmail.com> wrote:
>
>> Hi,
>> I am using :
>>
>> Server version: Apache Tomcat/6.0.32
>> OS Name: Mac OS X
>> OS Version: 10.6.8
>> Architecture: x86_64
>> JVM Version: 1.6.0_29-b11-402-10M3527
>>
>> Thanks,
>> Ravi
>>
>>
>> On Tue, Dec 20, 2011 at 4:52 PM, Pid * <pi...@pidster.com> wrote:
>>
>>> On 20 Dec 2011, at 11:02, S B <sb...@gmail.com> wrote:
>>>
>>>> Hi,
>>>>
>>>> I created and deployed an MBean in my tomcat. It uses datasource to
>>> connect
>>>> to DB.
>>>
>>> Which version of Java? Tomcat?
>>>
>>>
>>>> My questions is:
>>>>
>>>> When I create InitialContext() inside MBean's constructor and pass the
>>>> envContext to DBManager class to lookup datasource it works fine.
>>> However
>>>> when I create InitialContext() in DBManager class, it fails.
>>>>
>>>> Is it necessary to create InitialContext() during loading of MBean
>>> (either
>>>> in ContextListener class or inside MBean constructor).
>>>
>>> It depends on where you run the code. You haven't told us this.
>>>
>>> Can you post a code example.
>>>
>>>
>>> p
>>>
>>>
>>>> When I did new InitialContext() in my DBManager class which is called
>>> from
>>>> hello method of MBean it failed with below exception:
>>>>
>>>> avax.naming.NoInitialContextException: Cannot instantiate class:
>>>> org.apache.naming.java.javaURLContextFactory [Root exception is
>>>> java.lang.ClassNotFoundException:
>>>> org.apache.naming.java.javaURLContextFactory]
>>>>
>>>> I invoked hello method of MBean from JConsole.
>>>>
>>>>
>>>> Please let me know is it Tomcat specific? or same behavior is seen
>>> across
>>>> all app servers. Also, What difference does it make if I create
>>>> InitialContext inside MBean's constructor or in some other class at a
>>> later
>>>> point of time.
>>>>
>>>> Thanks
>>>> Ravi
>>>
>>> ---------------------------------------------------------------------
>>> To unsubscribe, e-mail: users-unsubscribe@tomcat.apache.org
>>> For additional commands, e-mail: users-help@tomcat.apache.org
>>>
>>>
>>
>
--
[key:62590808]
Re: MBean InitialContext() Tomcat query- pls help
Posted by S B <sb...@gmail.com>.
Code Sample that fails with exception(I am invoking reload() from jconsole
):
class MBeanImpl implements MBeanInterface{
public MBeanImpl{
// code to register this bean.
}
@Override
public void reload() {
DBManager.loadFromDB();
}
}
class DBManager{
public static void loadFromDB(){
InitialContext initContext = new
InitialContext(); // here it fails with exception
avax.naming.NoInitialContextException: Cannot instantiate class:
org.apache.naming.java.javaURLContextFactory [Root
// exception is java.lang.ClassNotFoundException:
org.apache.naming.java.javaURLContextFactory]
Context context = (Context)
initContext.lookup("java:comp/env");
logger.info("context found " + context);
BasicDataSource ds = (BasicDataSource)
context.lookup("jdbc/" + dataSourceName);
...............
...............
}
}
---------------------------------------------
Code Sample that works:
class MBeanImpl implements MBeanInterface{
private Context envContext = null;
public MBeanImpl{
InitialContext initialContext = new InitialContext();
envContext = (Context) initialContext.lookup("java:/comp/env");
// code to register this bean.
}
@Override
public void reload() {
DBManager.loadFromDB(envContext); // passed context object
obtained in constructor
}
}
class DBManager{
public static void loadFromDB(Context context){
BasicDataSource ds = (BasicDataSource)
context.lookup("jdbc/" + dataSourceName); // works fine as I am not
creating new InitialContext here.
...............
...............
}
}
On Tue, Dec 20, 2011 at 4:59 PM, S B <sb...@gmail.com> wrote:
> Hi,
> I am using :
>
> Server version: Apache Tomcat/6.0.32
> OS Name: Mac OS X
> OS Version: 10.6.8
> Architecture: x86_64
> JVM Version: 1.6.0_29-b11-402-10M3527
>
> Thanks,
> Ravi
>
>
> On Tue, Dec 20, 2011 at 4:52 PM, Pid * <pi...@pidster.com> wrote:
>
>> On 20 Dec 2011, at 11:02, S B <sb...@gmail.com> wrote:
>>
>> > Hi,
>> >
>> > I created and deployed an MBean in my tomcat. It uses datasource to
>> connect
>> > to DB.
>>
>> Which version of Java? Tomcat?
>>
>>
>> > My questions is:
>> >
>> > When I create InitialContext() inside MBean's constructor and pass the
>> > envContext to DBManager class to lookup datasource it works fine.
>> However
>> > when I create InitialContext() in DBManager class, it fails.
>> >
>> > Is it necessary to create InitialContext() during loading of MBean
>> (either
>> > in ContextListener class or inside MBean constructor).
>>
>> It depends on where you run the code. You haven't told us this.
>>
>> Can you post a code example.
>>
>>
>> p
>>
>>
>> > When I did new InitialContext() in my DBManager class which is called
>> from
>> > hello method of MBean it failed with below exception:
>> >
>> > avax.naming.NoInitialContextException: Cannot instantiate class:
>> > org.apache.naming.java.javaURLContextFactory [Root exception is
>> > java.lang.ClassNotFoundException:
>> > org.apache.naming.java.javaURLContextFactory]
>> >
>> > I invoked hello method of MBean from JConsole.
>> >
>> >
>> > Please let me know is it Tomcat specific? or same behavior is seen
>> across
>> > all app servers. Also, What difference does it make if I create
>> > InitialContext inside MBean's constructor or in some other class at a
>> later
>> > point of time.
>> >
>> > Thanks
>> > Ravi
>>
>> ---------------------------------------------------------------------
>> To unsubscribe, e-mail: users-unsubscribe@tomcat.apache.org
>> For additional commands, e-mail: users-help@tomcat.apache.org
>>
>>
>
Re: MBean InitialContext() Tomcat query- pls help
Posted by S B <sb...@gmail.com>.
Hi,
I am using :
Server version: Apache Tomcat/6.0.32
OS Name: Mac OS X
OS Version: 10.6.8
Architecture: x86_64
JVM Version: 1.6.0_29-b11-402-10M3527
Thanks,
Ravi
On Tue, Dec 20, 2011 at 4:52 PM, Pid * <pi...@pidster.com> wrote:
> On 20 Dec 2011, at 11:02, S B <sb...@gmail.com> wrote:
>
> > Hi,
> >
> > I created and deployed an MBean in my tomcat. It uses datasource to
> connect
> > to DB.
>
> Which version of Java? Tomcat?
>
>
> > My questions is:
> >
> > When I create InitialContext() inside MBean's constructor and pass the
> > envContext to DBManager class to lookup datasource it works fine. However
> > when I create InitialContext() in DBManager class, it fails.
> >
> > Is it necessary to create InitialContext() during loading of MBean
> (either
> > in ContextListener class or inside MBean constructor).
>
> It depends on where you run the code. You haven't told us this.
>
> Can you post a code example.
>
>
> p
>
>
> > When I did new InitialContext() in my DBManager class which is called
> from
> > hello method of MBean it failed with below exception:
> >
> > avax.naming.NoInitialContextException: Cannot instantiate class:
> > org.apache.naming.java.javaURLContextFactory [Root exception is
> > java.lang.ClassNotFoundException:
> > org.apache.naming.java.javaURLContextFactory]
> >
> > I invoked hello method of MBean from JConsole.
> >
> >
> > Please let me know is it Tomcat specific? or same behavior is seen across
> > all app servers. Also, What difference does it make if I create
> > InitialContext inside MBean's constructor or in some other class at a
> later
> > point of time.
> >
> > Thanks
> > Ravi
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: users-unsubscribe@tomcat.apache.org
> For additional commands, e-mail: users-help@tomcat.apache.org
>
>
Re: MBean InitialContext() Tomcat query- pls help
Posted by Pid * <pi...@pidster.com>.
On 20 Dec 2011, at 11:02, S B <sb...@gmail.com> wrote:
> Hi,
>
> I created and deployed an MBean in my tomcat. It uses datasource to connect
> to DB.
Which version of Java? Tomcat?
> My questions is:
>
> When I create InitialContext() inside MBean's constructor and pass the
> envContext to DBManager class to lookup datasource it works fine. However
> when I create InitialContext() in DBManager class, it fails.
>
> Is it necessary to create InitialContext() during loading of MBean (either
> in ContextListener class or inside MBean constructor).
It depends on where you run the code. You haven't told us this.
Can you post a code example.
p
> When I did new InitialContext() in my DBManager class which is called from
> hello method of MBean it failed with below exception:
>
> avax.naming.NoInitialContextException: Cannot instantiate class:
> org.apache.naming.java.javaURLContextFactory [Root exception is
> java.lang.ClassNotFoundException:
> org.apache.naming.java.javaURLContextFactory]
>
> I invoked hello method of MBean from JConsole.
>
>
> Please let me know is it Tomcat specific? or same behavior is seen across
> all app servers. Also, What difference does it make if I create
> InitialContext inside MBean's constructor or in some other class at a later
> point of time.
>
> Thanks
> Ravi
---------------------------------------------------------------------
To unsubscribe, e-mail: users-unsubscribe@tomcat.apache.org
For additional commands, e-mail: users-help@tomcat.apache.org
Re: MBean InitialContext() Tomcat query- pls help
Posted by S B <sb...@gmail.com>.
On Tue, Dec 27, 2011 at 6:55 PM, Konstantin Kolinko
<kn...@gmail.com>wrote:
> 2011/12/27 S B <sb...@gmail.com>:
> > On Tue, Dec 27, 2011 at 4:53 PM, Pid * <pi...@pidster.com> wrote:
> >
> >> On 27 Dec 2011, at 11:16, S B <sb...@gmail.com> wrote:
> >>
> >> > On Tue, Dec 27, 2011 at 4:06 PM, Pid * <pi...@pidster.com> wrote:
> >> >
> >> >> On 27 Dec 2011, at 01:33, S B <sb...@gmail.com> wrote:
> >> >>
> >> >>> On Mon, Dec 26, 2011 at 3:28 PM, Pid * <pi...@pidster.com> wrote:
> >> >>>
> >> >>>> On 26 Dec 2011, at 09:50, S B <sb...@gmail.com> wrote:
> >> >>>>
> >> >>>>> On Sat, Dec 24, 2011 at 6:29 PM, Pid <pi...@pidster.com> wrote:
> >> >>>>>
> >> >>>>>> On 23/12/2011 04:57, S B wrote:
> >> >>>>>>> On Thu, Dec 22, 2011 at 8:49 PM, Pid <pi...@pidster.com> wrote:
> >> >>>>>>>
> >> >>>>>>>> On 22/12/2011 10:34, Konstantin Kolinko wrote:
> >> >>>>>>>>> 2011/12/20 S B <sb...@gmail.com>:
> >> >>>>>>>>>> Hi,
> >> >>>>>>>>>>
> >> >>>>>>>>>> I created and deployed an MBean in my tomcat. It uses
> datasource
> >> >> to
> >> >>>>>>>> connect
> >> >>>>>>>>>> to DB.
> >> >>>>>>>>>>
> >> >>>>>>>>>> My questions is:
> >> >>>>>>>>>>
> >> >>>>>>>>>> When I create InitialContext() inside MBean's constructor and
> >> pass
> >> >>>> the
> >> >>>>>>>>>> envContext to DBManager class to lookup datasource it works
> >> fine.
> >> >>>>>>>> However
> >> >>>>>>>>>> when I create InitialContext() in DBManager class, it fails.
> >> >>>>>>>>>
> >> >>>>>>>>> IIRC what InitialContext() sees as its environment highly
> depends
> >> >> on
> >> >>>>>>>>> what classloader is active. That is TCCL =
> >> >>>>>>>>> Thread.getContextClassLoader().
> >> >>>>>>>>>
> >> >>>>>>>>> So while it is run from within web application your TCCL =
> your
> >> >>>>>>>>> webapp's classloader.
> >> >>>>>>>>>
> >> >>>>>>>>> When it is invoked from jconsole it might be a separate
> Thread,
> >> not
> >> >>>>>>>>> related to your web application.
> >> >>>>>>>>
> >> >>>>>>>>
> >> >>>>>>>> Like he ^^^ said. :)
> >> >>>>>>>>
> >> >>>>>>>>
> >> >>>>>>>> p
> >> >>>>>>>>
> >> >>>>>>>>
> >> >>>>>>>> --
> >> >>>>>>>>
> >> >>>>>>>> [key:62590808]
> >> >>>>>>>>
> >> >>>>>>>>
> >> >>>>>>> Hi Pid/Konstantin,
> >> >>>>>>>
> >> >>>>>>> yes you are right. I just verified it. When it is invoked from
> >> >>>> jconsole,
> >> >>>>>>> the classloader is: sun.misc.Launcher$AppClassLoader@61e63e3d
> >> >>>>>>> and when it is run within a web application the clasloader is
> >> >>>>>>> WebAppClassloader.
> >> >>>>>>>
> >> >>>>>>> So, how can I force it to use webapp classloader during new
> >> >>>>>>> InitialContext() while invoking from jconsole
> >> >>>>>>> One possible way is to reuse the initialContext created during
> >> server
> >> >>>>>>> startup. (pass it as param during invocation from jconsole).
> >> >>>>>>>
> >> >>>>>>> Is there a smarter way ??
> >> >>>>>>
> >> >>>>>> I am a bit concerned about how you are registering the bean
> inside
> >> the
> >> >>>>>> bean's own constructor. I am not clear on how you are
> subsequently
> >> >>>>>> unregistering that bean, before the reloading operation - and I
> am
> >> not
> >> >>>>>> at all clear what the purpose of reloading is anyway.
> >> >>>>>>
> >> >>>>>> Is there a reason that the MBean itself needs to be recreated?
> >> >>>>>>
> >> >>>>>> Bear in mind that you are attempting to re-initialise the MBean,
> >> while
> >> >>>>>> you are still using it. This does not seem like a good idea to
> me.
> >> >>>>>>
> >> >>>>>> I would suggest that you either have a separate Manager MBean
> that
> >> >> does
> >> >>>>>> the reloading, or just have the reload method call the actual
> code
> >> on
> >> >>>>>> the DB, without re-initialising the bean.
> >> >>>>>>
> >> >>>>>>
> >> >>>>>> p
> >> >>>>>>
> >> >>>>>>
> >> >>>>>> --
> >> >>>>>>
> >> >>>>>> [key:62590808]
> >> >>>>>>
> >> >>>>>>
> >> >>>>> Hi,
> >> >>>>>
> >> >>>>> un-registering of mbean doesn't happen until servlet's destroy
> method
> >> >> is
> >> >>>>> called.
> >> >>>>> Actually, registration of bean happen only once, ie during server
> >> >>>> startup.
> >> >>>>> This time mbean's constructor is called and it is registered with
> >> MBean
> >> >>>>> server.
> >> >>>>> (I was wrong earlier when I said, constructor is called on each
> >> >>>> invocation
> >> >>>>> of reload() method from jconsole. sorry about that. i was lill
> >> >> confused.)
> >> >>>>>
> >> >>>>> MBean is never re-created. It is created only once and registered
> >> only
> >> >>>> once.
> >> >>>>>
> >> >>>>> actual flow is:
> >> >>>>>
> >> >>>>> click reload() on jconsole gui.
> >> >>>>> *it causes constructor of MBeanImpl to run. (verified from logs.)*
> >> --
> >> >>>> *Wrong.
> >> >>>>> pls disregard this statement.*
> >> >>>>> calls reload() defined in MBeanImpl.
> >> >>>>> calls DBManager.reload()
> >> >>>>> inside DBManager.reload() it fails at InitialContext initContext =
> >> new
> >> >>>>> InitialContext();
> >> >>>>> the exception is - javax.naming.NoInitialContextException:
> Cannot
> >> >>>>> instantiate class: org.apache.naming.java.javaURLContextFactory
> [Root
> >> >>>>> exception is java.lang.ClassNotFoundException:
> >> >>>>> org.apache.naming.java.javaURLContextFactory]
> >> >>>>
> >> >>>> OK, but what is the purpose of DBManager.reload()?
> >> >>>>
> >> >>>>
> >> >>>> p
> >> >>>>
> >> >>>>
> ---------------------------------------------------------------------
> >> >>>> To unsubscribe, e-mail: users-unsubscribe@tomcat.apache.org
> >> >>>> For additional commands, e-mail: users-help@tomcat.apache.org
> >> >>>>
> >> >>>>
> >> >>>
> >> >>> Hi Pid, Marry Christmas !!!
> >> >>> Purpose of DBManager.reload() is to load some application specific
> data
> >> >>> from DB. Pls don't consider reload() as reload of MBean.
> >> >>> reload() can better be renamed as loadData().
> >> >>>
> >> >>> when I invoke reload() from jconsole my application is suppose to
> make
> >> a
> >> >> db
> >> >>> connection and load app specific data from database.
> >> >>
> >> >> OK, so why not retain a reference to the DataSource that you're
> >> >> getting the connection from?
> >> >>
> >> >>
> >> >> p
> >> >>
> >> >> ---------------------------------------------------------------------
> >> >> To unsubscribe, e-mail: users-unsubscribe@tomcat.apache.org
> >> >> For additional commands, e-mail: users-help@tomcat.apache.org
> >> >>
> >> >>
> >> > yes. thats one possible workaround. I followed similar approach and
> >> > retailed reference of Context (which i used to get datasource during
> >> > invocation from jconsole).
> >> > This approach works.
> >> > And as Konstantin earlier said it is because of different class
> loaders
> >> > that I can't do "new InitialContext()" during invocation from
> jconsole.
> >> > *My question is: how can I force it to use webapp classloader during
> new
> >> > InitialContext() while invoking from jconsole.*
> >> >
> >> > is there a way to do something like
> >> > InitialContext.useClassLoader(webaappClassLoader)
> >> > ?
> >> > During server startup InitialContext() used webapp classloader and
> during
> >> > invocation of mbean from jconsole it was some other classloader hence
> "
> >> new
> >> > InitialContext()" failed.
> >> >
> >> > you got my question ?
> >>
> >>
> >> Yes. I got it.
> >>
> >> I'm not trying to find a solution because I'm not sure why you insist
> >> on doing things the hard way when there is a perfectly reasonable
> >> alternative.
> >>
> >>
> >>
> > That's fine. I just wanted to confirm whether the reference-retention
> > approach is the smartest one or there are any better solution available.
> > Thanks for your help.
>
> Either way you have to retain a reference. Be it a WebappClassLoader
> reference (and call Thread.setContextClassLoader()) or an object
> reference.
>
> The purpose of JNDI is to provide access to configuration. Once you
> did the lookup it is better to keep the obtained value.
>
> > :)
>
> Best regards,
> Konstantin Kolinko
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: users-unsubscribe@tomcat.apache.org
> For additional commands, e-mail: users-help@tomcat.apache.org
>
>
Yes. That makes sense.
Thanks :)
Re: MBean InitialContext() Tomcat query- pls help
Posted by Konstantin Kolinko <kn...@gmail.com>.
2011/12/27 S B <sb...@gmail.com>:
> On Tue, Dec 27, 2011 at 4:53 PM, Pid * <pi...@pidster.com> wrote:
>
>> On 27 Dec 2011, at 11:16, S B <sb...@gmail.com> wrote:
>>
>> > On Tue, Dec 27, 2011 at 4:06 PM, Pid * <pi...@pidster.com> wrote:
>> >
>> >> On 27 Dec 2011, at 01:33, S B <sb...@gmail.com> wrote:
>> >>
>> >>> On Mon, Dec 26, 2011 at 3:28 PM, Pid * <pi...@pidster.com> wrote:
>> >>>
>> >>>> On 26 Dec 2011, at 09:50, S B <sb...@gmail.com> wrote:
>> >>>>
>> >>>>> On Sat, Dec 24, 2011 at 6:29 PM, Pid <pi...@pidster.com> wrote:
>> >>>>>
>> >>>>>> On 23/12/2011 04:57, S B wrote:
>> >>>>>>> On Thu, Dec 22, 2011 at 8:49 PM, Pid <pi...@pidster.com> wrote:
>> >>>>>>>
>> >>>>>>>> On 22/12/2011 10:34, Konstantin Kolinko wrote:
>> >>>>>>>>> 2011/12/20 S B <sb...@gmail.com>:
>> >>>>>>>>>> Hi,
>> >>>>>>>>>>
>> >>>>>>>>>> I created and deployed an MBean in my tomcat. It uses datasource
>> >> to
>> >>>>>>>> connect
>> >>>>>>>>>> to DB.
>> >>>>>>>>>>
>> >>>>>>>>>> My questions is:
>> >>>>>>>>>>
>> >>>>>>>>>> When I create InitialContext() inside MBean's constructor and
>> pass
>> >>>> the
>> >>>>>>>>>> envContext to DBManager class to lookup datasource it works
>> fine.
>> >>>>>>>> However
>> >>>>>>>>>> when I create InitialContext() in DBManager class, it fails.
>> >>>>>>>>>
>> >>>>>>>>> IIRC what InitialContext() sees as its environment highly depends
>> >> on
>> >>>>>>>>> what classloader is active. That is TCCL =
>> >>>>>>>>> Thread.getContextClassLoader().
>> >>>>>>>>>
>> >>>>>>>>> So while it is run from within web application your TCCL = your
>> >>>>>>>>> webapp's classloader.
>> >>>>>>>>>
>> >>>>>>>>> When it is invoked from jconsole it might be a separate Thread,
>> not
>> >>>>>>>>> related to your web application.
>> >>>>>>>>
>> >>>>>>>>
>> >>>>>>>> Like he ^^^ said. :)
>> >>>>>>>>
>> >>>>>>>>
>> >>>>>>>> p
>> >>>>>>>>
>> >>>>>>>>
>> >>>>>>>> --
>> >>>>>>>>
>> >>>>>>>> [key:62590808]
>> >>>>>>>>
>> >>>>>>>>
>> >>>>>>> Hi Pid/Konstantin,
>> >>>>>>>
>> >>>>>>> yes you are right. I just verified it. When it is invoked from
>> >>>> jconsole,
>> >>>>>>> the classloader is: sun.misc.Launcher$AppClassLoader@61e63e3d
>> >>>>>>> and when it is run within a web application the clasloader is
>> >>>>>>> WebAppClassloader.
>> >>>>>>>
>> >>>>>>> So, how can I force it to use webapp classloader during new
>> >>>>>>> InitialContext() while invoking from jconsole
>> >>>>>>> One possible way is to reuse the initialContext created during
>> server
>> >>>>>>> startup. (pass it as param during invocation from jconsole).
>> >>>>>>>
>> >>>>>>> Is there a smarter way ??
>> >>>>>>
>> >>>>>> I am a bit concerned about how you are registering the bean inside
>> the
>> >>>>>> bean's own constructor. I am not clear on how you are subsequently
>> >>>>>> unregistering that bean, before the reloading operation - and I am
>> not
>> >>>>>> at all clear what the purpose of reloading is anyway.
>> >>>>>>
>> >>>>>> Is there a reason that the MBean itself needs to be recreated?
>> >>>>>>
>> >>>>>> Bear in mind that you are attempting to re-initialise the MBean,
>> while
>> >>>>>> you are still using it. This does not seem like a good idea to me.
>> >>>>>>
>> >>>>>> I would suggest that you either have a separate Manager MBean that
>> >> does
>> >>>>>> the reloading, or just have the reload method call the actual code
>> on
>> >>>>>> the DB, without re-initialising the bean.
>> >>>>>>
>> >>>>>>
>> >>>>>> p
>> >>>>>>
>> >>>>>>
>> >>>>>> --
>> >>>>>>
>> >>>>>> [key:62590808]
>> >>>>>>
>> >>>>>>
>> >>>>> Hi,
>> >>>>>
>> >>>>> un-registering of mbean doesn't happen until servlet's destroy method
>> >> is
>> >>>>> called.
>> >>>>> Actually, registration of bean happen only once, ie during server
>> >>>> startup.
>> >>>>> This time mbean's constructor is called and it is registered with
>> MBean
>> >>>>> server.
>> >>>>> (I was wrong earlier when I said, constructor is called on each
>> >>>> invocation
>> >>>>> of reload() method from jconsole. sorry about that. i was lill
>> >> confused.)
>> >>>>>
>> >>>>> MBean is never re-created. It is created only once and registered
>> only
>> >>>> once.
>> >>>>>
>> >>>>> actual flow is:
>> >>>>>
>> >>>>> click reload() on jconsole gui.
>> >>>>> *it causes constructor of MBeanImpl to run. (verified from logs.)*
>> --
>> >>>> *Wrong.
>> >>>>> pls disregard this statement.*
>> >>>>> calls reload() defined in MBeanImpl.
>> >>>>> calls DBManager.reload()
>> >>>>> inside DBManager.reload() it fails at InitialContext initContext =
>> new
>> >>>>> InitialContext();
>> >>>>> the exception is - javax.naming.NoInitialContextException: Cannot
>> >>>>> instantiate class: org.apache.naming.java.javaURLContextFactory [Root
>> >>>>> exception is java.lang.ClassNotFoundException:
>> >>>>> org.apache.naming.java.javaURLContextFactory]
>> >>>>
>> >>>> OK, but what is the purpose of DBManager.reload()?
>> >>>>
>> >>>>
>> >>>> p
>> >>>>
>> >>>> ---------------------------------------------------------------------
>> >>>> To unsubscribe, e-mail: users-unsubscribe@tomcat.apache.org
>> >>>> For additional commands, e-mail: users-help@tomcat.apache.org
>> >>>>
>> >>>>
>> >>>
>> >>> Hi Pid, Marry Christmas !!!
>> >>> Purpose of DBManager.reload() is to load some application specific data
>> >>> from DB. Pls don't consider reload() as reload of MBean.
>> >>> reload() can better be renamed as loadData().
>> >>>
>> >>> when I invoke reload() from jconsole my application is suppose to make
>> a
>> >> db
>> >>> connection and load app specific data from database.
>> >>
>> >> OK, so why not retain a reference to the DataSource that you're
>> >> getting the connection from?
>> >>
>> >>
>> >> p
>> >>
>> >> ---------------------------------------------------------------------
>> >> To unsubscribe, e-mail: users-unsubscribe@tomcat.apache.org
>> >> For additional commands, e-mail: users-help@tomcat.apache.org
>> >>
>> >>
>> > yes. thats one possible workaround. I followed similar approach and
>> > retailed reference of Context (which i used to get datasource during
>> > invocation from jconsole).
>> > This approach works.
>> > And as Konstantin earlier said it is because of different class loaders
>> > that I can't do "new InitialContext()" during invocation from jconsole.
>> > *My question is: how can I force it to use webapp classloader during new
>> > InitialContext() while invoking from jconsole.*
>> >
>> > is there a way to do something like
>> > InitialContext.useClassLoader(webaappClassLoader)
>> > ?
>> > During server startup InitialContext() used webapp classloader and during
>> > invocation of mbean from jconsole it was some other classloader hence "
>> new
>> > InitialContext()" failed.
>> >
>> > you got my question ?
>>
>>
>> Yes. I got it.
>>
>> I'm not trying to find a solution because I'm not sure why you insist
>> on doing things the hard way when there is a perfectly reasonable
>> alternative.
>>
>>
>>
> That's fine. I just wanted to confirm whether the reference-retention
> approach is the smartest one or there are any better solution available.
> Thanks for your help.
Either way you have to retain a reference. Be it a WebappClassLoader
reference (and call Thread.setContextClassLoader()) or an object
reference.
The purpose of JNDI is to provide access to configuration. Once you
did the lookup it is better to keep the obtained value.
> :)
Best regards,
Konstantin Kolinko
---------------------------------------------------------------------
To unsubscribe, e-mail: users-unsubscribe@tomcat.apache.org
For additional commands, e-mail: users-help@tomcat.apache.org
Re: MBean InitialContext() Tomcat query- pls help
Posted by S B <sb...@gmail.com>.
On Tue, Dec 27, 2011 at 4:53 PM, Pid * <pi...@pidster.com> wrote:
> On 27 Dec 2011, at 11:16, S B <sb...@gmail.com> wrote:
>
> > On Tue, Dec 27, 2011 at 4:06 PM, Pid * <pi...@pidster.com> wrote:
> >
> >> On 27 Dec 2011, at 01:33, S B <sb...@gmail.com> wrote:
> >>
> >>> On Mon, Dec 26, 2011 at 3:28 PM, Pid * <pi...@pidster.com> wrote:
> >>>
> >>>> On 26 Dec 2011, at 09:50, S B <sb...@gmail.com> wrote:
> >>>>
> >>>>> On Sat, Dec 24, 2011 at 6:29 PM, Pid <pi...@pidster.com> wrote:
> >>>>>
> >>>>>> On 23/12/2011 04:57, S B wrote:
> >>>>>>> On Thu, Dec 22, 2011 at 8:49 PM, Pid <pi...@pidster.com> wrote:
> >>>>>>>
> >>>>>>>> On 22/12/2011 10:34, Konstantin Kolinko wrote:
> >>>>>>>>> 2011/12/20 S B <sb...@gmail.com>:
> >>>>>>>>>> Hi,
> >>>>>>>>>>
> >>>>>>>>>> I created and deployed an MBean in my tomcat. It uses datasource
> >> to
> >>>>>>>> connect
> >>>>>>>>>> to DB.
> >>>>>>>>>>
> >>>>>>>>>> My questions is:
> >>>>>>>>>>
> >>>>>>>>>> When I create InitialContext() inside MBean's constructor and
> pass
> >>>> the
> >>>>>>>>>> envContext to DBManager class to lookup datasource it works
> fine.
> >>>>>>>> However
> >>>>>>>>>> when I create InitialContext() in DBManager class, it fails.
> >>>>>>>>>
> >>>>>>>>> IIRC what InitialContext() sees as its environment highly depends
> >> on
> >>>>>>>>> what classloader is active. That is TCCL =
> >>>>>>>>> Thread.getContextClassLoader().
> >>>>>>>>>
> >>>>>>>>> So while it is run from within web application your TCCL = your
> >>>>>>>>> webapp's classloader.
> >>>>>>>>>
> >>>>>>>>> When it is invoked from jconsole it might be a separate Thread,
> not
> >>>>>>>>> related to your web application.
> >>>>>>>>
> >>>>>>>>
> >>>>>>>> Like he ^^^ said. :)
> >>>>>>>>
> >>>>>>>>
> >>>>>>>> p
> >>>>>>>>
> >>>>>>>>
> >>>>>>>> --
> >>>>>>>>
> >>>>>>>> [key:62590808]
> >>>>>>>>
> >>>>>>>>
> >>>>>>> Hi Pid/Konstantin,
> >>>>>>>
> >>>>>>> yes you are right. I just verified it. When it is invoked from
> >>>> jconsole,
> >>>>>>> the classloader is: sun.misc.Launcher$AppClassLoader@61e63e3d
> >>>>>>> and when it is run within a web application the clasloader is
> >>>>>>> WebAppClassloader.
> >>>>>>>
> >>>>>>> So, how can I force it to use webapp classloader during new
> >>>>>>> InitialContext() while invoking from jconsole
> >>>>>>> One possible way is to reuse the initialContext created during
> server
> >>>>>>> startup. (pass it as param during invocation from jconsole).
> >>>>>>>
> >>>>>>> Is there a smarter way ??
> >>>>>>
> >>>>>> I am a bit concerned about how you are registering the bean inside
> the
> >>>>>> bean's own constructor. I am not clear on how you are subsequently
> >>>>>> unregistering that bean, before the reloading operation - and I am
> not
> >>>>>> at all clear what the purpose of reloading is anyway.
> >>>>>>
> >>>>>> Is there a reason that the MBean itself needs to be recreated?
> >>>>>>
> >>>>>> Bear in mind that you are attempting to re-initialise the MBean,
> while
> >>>>>> you are still using it. This does not seem like a good idea to me.
> >>>>>>
> >>>>>> I would suggest that you either have a separate Manager MBean that
> >> does
> >>>>>> the reloading, or just have the reload method call the actual code
> on
> >>>>>> the DB, without re-initialising the bean.
> >>>>>>
> >>>>>>
> >>>>>> p
> >>>>>>
> >>>>>>
> >>>>>> --
> >>>>>>
> >>>>>> [key:62590808]
> >>>>>>
> >>>>>>
> >>>>> Hi,
> >>>>>
> >>>>> un-registering of mbean doesn't happen until servlet's destroy method
> >> is
> >>>>> called.
> >>>>> Actually, registration of bean happen only once, ie during server
> >>>> startup.
> >>>>> This time mbean's constructor is called and it is registered with
> MBean
> >>>>> server.
> >>>>> (I was wrong earlier when I said, constructor is called on each
> >>>> invocation
> >>>>> of reload() method from jconsole. sorry about that. i was lill
> >> confused.)
> >>>>>
> >>>>> MBean is never re-created. It is created only once and registered
> only
> >>>> once.
> >>>>>
> >>>>> actual flow is:
> >>>>>
> >>>>> click reload() on jconsole gui.
> >>>>> *it causes constructor of MBeanImpl to run. (verified from logs.)*
> --
> >>>> *Wrong.
> >>>>> pls disregard this statement.*
> >>>>> calls reload() defined in MBeanImpl.
> >>>>> calls DBManager.reload()
> >>>>> inside DBManager.reload() it fails at InitialContext initContext =
> new
> >>>>> InitialContext();
> >>>>> the exception is - javax.naming.NoInitialContextException: Cannot
> >>>>> instantiate class: org.apache.naming.java.javaURLContextFactory [Root
> >>>>> exception is java.lang.ClassNotFoundException:
> >>>>> org.apache.naming.java.javaURLContextFactory]
> >>>>
> >>>> OK, but what is the purpose of DBManager.reload()?
> >>>>
> >>>>
> >>>> p
> >>>>
> >>>> ---------------------------------------------------------------------
> >>>> To unsubscribe, e-mail: users-unsubscribe@tomcat.apache.org
> >>>> For additional commands, e-mail: users-help@tomcat.apache.org
> >>>>
> >>>>
> >>>
> >>> Hi Pid, Marry Christmas !!!
> >>> Purpose of DBManager.reload() is to load some application specific data
> >>> from DB. Pls don't consider reload() as reload of MBean.
> >>> reload() can better be renamed as loadData().
> >>>
> >>> when I invoke reload() from jconsole my application is suppose to make
> a
> >> db
> >>> connection and load app specific data from database.
> >>
> >> OK, so why not retain a reference to the DataSource that you're
> >> getting the connection from?
> >>
> >>
> >> p
> >>
> >> ---------------------------------------------------------------------
> >> To unsubscribe, e-mail: users-unsubscribe@tomcat.apache.org
> >> For additional commands, e-mail: users-help@tomcat.apache.org
> >>
> >>
> > yes. thats one possible workaround. I followed similar approach and
> > retailed reference of Context (which i used to get datasource during
> > invocation from jconsole).
> > This approach works.
> > And as Konstantin earlier said it is because of different class loaders
> > that I can't do "new InitialContext()" during invocation from jconsole.
> > *My question is: how can I force it to use webapp classloader during new
> > InitialContext() while invoking from jconsole.*
> >
> > is there a way to do something like
> > InitialContext.useClassLoader(webaappClassLoader)
> > ?
> > During server startup InitialContext() used webapp classloader and during
> > invocation of mbean from jconsole it was some other classloader hence "
> new
> > InitialContext()" failed.
> >
> > you got my question ?
>
>
> Yes. I got it.
>
> I'm not trying to find a solution because I'm not sure why you insist
> on doing things the hard way when there is a perfectly reasonable
> alternative.
>
>
> p
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: users-unsubscribe@tomcat.apache.org
> For additional commands, e-mail: users-help@tomcat.apache.org
>
>
That's fine. I just wanted to confirm whether the reference-retention
approach is the smartest one or there are any better solution available.
Thanks for your help.
:)
Re: MBean InitialContext() Tomcat query- pls help
Posted by Pid * <pi...@pidster.com>.
On 27 Dec 2011, at 11:16, S B <sb...@gmail.com> wrote:
> On Tue, Dec 27, 2011 at 4:06 PM, Pid * <pi...@pidster.com> wrote:
>
>> On 27 Dec 2011, at 01:33, S B <sb...@gmail.com> wrote:
>>
>>> On Mon, Dec 26, 2011 at 3:28 PM, Pid * <pi...@pidster.com> wrote:
>>>
>>>> On 26 Dec 2011, at 09:50, S B <sb...@gmail.com> wrote:
>>>>
>>>>> On Sat, Dec 24, 2011 at 6:29 PM, Pid <pi...@pidster.com> wrote:
>>>>>
>>>>>> On 23/12/2011 04:57, S B wrote:
>>>>>>> On Thu, Dec 22, 2011 at 8:49 PM, Pid <pi...@pidster.com> wrote:
>>>>>>>
>>>>>>>> On 22/12/2011 10:34, Konstantin Kolinko wrote:
>>>>>>>>> 2011/12/20 S B <sb...@gmail.com>:
>>>>>>>>>> Hi,
>>>>>>>>>>
>>>>>>>>>> I created and deployed an MBean in my tomcat. It uses datasource
>> to
>>>>>>>> connect
>>>>>>>>>> to DB.
>>>>>>>>>>
>>>>>>>>>> My questions is:
>>>>>>>>>>
>>>>>>>>>> When I create InitialContext() inside MBean's constructor and pass
>>>> the
>>>>>>>>>> envContext to DBManager class to lookup datasource it works fine.
>>>>>>>> However
>>>>>>>>>> when I create InitialContext() in DBManager class, it fails.
>>>>>>>>>
>>>>>>>>> IIRC what InitialContext() sees as its environment highly depends
>> on
>>>>>>>>> what classloader is active. That is TCCL =
>>>>>>>>> Thread.getContextClassLoader().
>>>>>>>>>
>>>>>>>>> So while it is run from within web application your TCCL = your
>>>>>>>>> webapp's classloader.
>>>>>>>>>
>>>>>>>>> When it is invoked from jconsole it might be a separate Thread, not
>>>>>>>>> related to your web application.
>>>>>>>>
>>>>>>>>
>>>>>>>> Like he ^^^ said. :)
>>>>>>>>
>>>>>>>>
>>>>>>>> p
>>>>>>>>
>>>>>>>>
>>>>>>>> --
>>>>>>>>
>>>>>>>> [key:62590808]
>>>>>>>>
>>>>>>>>
>>>>>>> Hi Pid/Konstantin,
>>>>>>>
>>>>>>> yes you are right. I just verified it. When it is invoked from
>>>> jconsole,
>>>>>>> the classloader is: sun.misc.Launcher$AppClassLoader@61e63e3d
>>>>>>> and when it is run within a web application the clasloader is
>>>>>>> WebAppClassloader.
>>>>>>>
>>>>>>> So, how can I force it to use webapp classloader during new
>>>>>>> InitialContext() while invoking from jconsole
>>>>>>> One possible way is to reuse the initialContext created during server
>>>>>>> startup. (pass it as param during invocation from jconsole).
>>>>>>>
>>>>>>> Is there a smarter way ??
>>>>>>
>>>>>> I am a bit concerned about how you are registering the bean inside the
>>>>>> bean's own constructor. I am not clear on how you are subsequently
>>>>>> unregistering that bean, before the reloading operation - and I am not
>>>>>> at all clear what the purpose of reloading is anyway.
>>>>>>
>>>>>> Is there a reason that the MBean itself needs to be recreated?
>>>>>>
>>>>>> Bear in mind that you are attempting to re-initialise the MBean, while
>>>>>> you are still using it. This does not seem like a good idea to me.
>>>>>>
>>>>>> I would suggest that you either have a separate Manager MBean that
>> does
>>>>>> the reloading, or just have the reload method call the actual code on
>>>>>> the DB, without re-initialising the bean.
>>>>>>
>>>>>>
>>>>>> p
>>>>>>
>>>>>>
>>>>>> --
>>>>>>
>>>>>> [key:62590808]
>>>>>>
>>>>>>
>>>>> Hi,
>>>>>
>>>>> un-registering of mbean doesn't happen until servlet's destroy method
>> is
>>>>> called.
>>>>> Actually, registration of bean happen only once, ie during server
>>>> startup.
>>>>> This time mbean's constructor is called and it is registered with MBean
>>>>> server.
>>>>> (I was wrong earlier when I said, constructor is called on each
>>>> invocation
>>>>> of reload() method from jconsole. sorry about that. i was lill
>> confused.)
>>>>>
>>>>> MBean is never re-created. It is created only once and registered only
>>>> once.
>>>>>
>>>>> actual flow is:
>>>>>
>>>>> click reload() on jconsole gui.
>>>>> *it causes constructor of MBeanImpl to run. (verified from logs.)* --
>>>> *Wrong.
>>>>> pls disregard this statement.*
>>>>> calls reload() defined in MBeanImpl.
>>>>> calls DBManager.reload()
>>>>> inside DBManager.reload() it fails at InitialContext initContext = new
>>>>> InitialContext();
>>>>> the exception is - javax.naming.NoInitialContextException: Cannot
>>>>> instantiate class: org.apache.naming.java.javaURLContextFactory [Root
>>>>> exception is java.lang.ClassNotFoundException:
>>>>> org.apache.naming.java.javaURLContextFactory]
>>>>
>>>> OK, but what is the purpose of DBManager.reload()?
>>>>
>>>>
>>>> p
>>>>
>>>> ---------------------------------------------------------------------
>>>> To unsubscribe, e-mail: users-unsubscribe@tomcat.apache.org
>>>> For additional commands, e-mail: users-help@tomcat.apache.org
>>>>
>>>>
>>>
>>> Hi Pid, Marry Christmas !!!
>>> Purpose of DBManager.reload() is to load some application specific data
>>> from DB. Pls don't consider reload() as reload of MBean.
>>> reload() can better be renamed as loadData().
>>>
>>> when I invoke reload() from jconsole my application is suppose to make a
>> db
>>> connection and load app specific data from database.
>>
>> OK, so why not retain a reference to the DataSource that you're
>> getting the connection from?
>>
>>
>> p
>>
>> ---------------------------------------------------------------------
>> To unsubscribe, e-mail: users-unsubscribe@tomcat.apache.org
>> For additional commands, e-mail: users-help@tomcat.apache.org
>>
>>
> yes. thats one possible workaround. I followed similar approach and
> retailed reference of Context (which i used to get datasource during
> invocation from jconsole).
> This approach works.
> And as Konstantin earlier said it is because of different class loaders
> that I can't do "new InitialContext()" during invocation from jconsole.
> *My question is: how can I force it to use webapp classloader during new
> InitialContext() while invoking from jconsole.*
>
> is there a way to do something like
> InitialContext.useClassLoader(webaappClassLoader)
> ?
> During server startup InitialContext() used webapp classloader and during
> invocation of mbean from jconsole it was some other classloader hence " new
> InitialContext()" failed.
>
> you got my question ?
Yes. I got it.
I'm not trying to find a solution because I'm not sure why you insist
on doing things the hard way when there is a perfectly reasonable
alternative.
p
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Re: MBean InitialContext() Tomcat query- pls help
Posted by S B <sb...@gmail.com>.
On Tue, Dec 27, 2011 at 4:06 PM, Pid * <pi...@pidster.com> wrote:
> On 27 Dec 2011, at 01:33, S B <sb...@gmail.com> wrote:
>
> > On Mon, Dec 26, 2011 at 3:28 PM, Pid * <pi...@pidster.com> wrote:
> >
> >> On 26 Dec 2011, at 09:50, S B <sb...@gmail.com> wrote:
> >>
> >>> On Sat, Dec 24, 2011 at 6:29 PM, Pid <pi...@pidster.com> wrote:
> >>>
> >>>> On 23/12/2011 04:57, S B wrote:
> >>>>> On Thu, Dec 22, 2011 at 8:49 PM, Pid <pi...@pidster.com> wrote:
> >>>>>
> >>>>>> On 22/12/2011 10:34, Konstantin Kolinko wrote:
> >>>>>>> 2011/12/20 S B <sb...@gmail.com>:
> >>>>>>>> Hi,
> >>>>>>>>
> >>>>>>>> I created and deployed an MBean in my tomcat. It uses datasource
> to
> >>>>>> connect
> >>>>>>>> to DB.
> >>>>>>>>
> >>>>>>>> My questions is:
> >>>>>>>>
> >>>>>>>> When I create InitialContext() inside MBean's constructor and pass
> >> the
> >>>>>>>> envContext to DBManager class to lookup datasource it works fine.
> >>>>>> However
> >>>>>>>> when I create InitialContext() in DBManager class, it fails.
> >>>>>>>
> >>>>>>> IIRC what InitialContext() sees as its environment highly depends
> on
> >>>>>>> what classloader is active. That is TCCL =
> >>>>>>> Thread.getContextClassLoader().
> >>>>>>>
> >>>>>>> So while it is run from within web application your TCCL = your
> >>>>>>> webapp's classloader.
> >>>>>>>
> >>>>>>> When it is invoked from jconsole it might be a separate Thread, not
> >>>>>>> related to your web application.
> >>>>>>
> >>>>>>
> >>>>>> Like he ^^^ said. :)
> >>>>>>
> >>>>>>
> >>>>>> p
> >>>>>>
> >>>>>>
> >>>>>> --
> >>>>>>
> >>>>>> [key:62590808]
> >>>>>>
> >>>>>>
> >>>>> Hi Pid/Konstantin,
> >>>>>
> >>>>> yes you are right. I just verified it. When it is invoked from
> >> jconsole,
> >>>>> the classloader is: sun.misc.Launcher$AppClassLoader@61e63e3d
> >>>>> and when it is run within a web application the clasloader is
> >>>>> WebAppClassloader.
> >>>>>
> >>>>> So, how can I force it to use webapp classloader during new
> >>>>> InitialContext() while invoking from jconsole
> >>>>> One possible way is to reuse the initialContext created during server
> >>>>> startup. (pass it as param during invocation from jconsole).
> >>>>>
> >>>>> Is there a smarter way ??
> >>>>
> >>>> I am a bit concerned about how you are registering the bean inside the
> >>>> bean's own constructor. I am not clear on how you are subsequently
> >>>> unregistering that bean, before the reloading operation - and I am not
> >>>> at all clear what the purpose of reloading is anyway.
> >>>>
> >>>> Is there a reason that the MBean itself needs to be recreated?
> >>>>
> >>>> Bear in mind that you are attempting to re-initialise the MBean, while
> >>>> you are still using it. This does not seem like a good idea to me.
> >>>>
> >>>> I would suggest that you either have a separate Manager MBean that
> does
> >>>> the reloading, or just have the reload method call the actual code on
> >>>> the DB, without re-initialising the bean.
> >>>>
> >>>>
> >>>> p
> >>>>
> >>>>
> >>>> --
> >>>>
> >>>> [key:62590808]
> >>>>
> >>>>
> >>> Hi,
> >>>
> >>> un-registering of mbean doesn't happen until servlet's destroy method
> is
> >>> called.
> >>> Actually, registration of bean happen only once, ie during server
> >> startup.
> >>> This time mbean's constructor is called and it is registered with MBean
> >>> server.
> >>> (I was wrong earlier when I said, constructor is called on each
> >> invocation
> >>> of reload() method from jconsole. sorry about that. i was lill
> confused.)
> >>>
> >>> MBean is never re-created. It is created only once and registered only
> >> once.
> >>>
> >>> actual flow is:
> >>>
> >>> click reload() on jconsole gui.
> >>> *it causes constructor of MBeanImpl to run. (verified from logs.)* --
> >> *Wrong.
> >>> pls disregard this statement.*
> >>> calls reload() defined in MBeanImpl.
> >>> calls DBManager.reload()
> >>> inside DBManager.reload() it fails at InitialContext initContext = new
> >>> InitialContext();
> >>> the exception is - javax.naming.NoInitialContextException: Cannot
> >>> instantiate class: org.apache.naming.java.javaURLContextFactory [Root
> >>> exception is java.lang.ClassNotFoundException:
> >>> org.apache.naming.java.javaURLContextFactory]
> >>
> >> OK, but what is the purpose of DBManager.reload()?
> >>
> >>
> >> p
> >>
> >> ---------------------------------------------------------------------
> >> To unsubscribe, e-mail: users-unsubscribe@tomcat.apache.org
> >> For additional commands, e-mail: users-help@tomcat.apache.org
> >>
> >>
> >
> > Hi Pid, Marry Christmas !!!
> > Purpose of DBManager.reload() is to load some application specific data
> > from DB. Pls don't consider reload() as reload of MBean.
> > reload() can better be renamed as loadData().
> >
> > when I invoke reload() from jconsole my application is suppose to make a
> db
> > connection and load app specific data from database.
>
> OK, so why not retain a reference to the DataSource that you're
> getting the connection from?
>
>
> p
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: users-unsubscribe@tomcat.apache.org
> For additional commands, e-mail: users-help@tomcat.apache.org
>
>
yes. thats one possible workaround. I followed similar approach and
retailed reference of Context (which i used to get datasource during
invocation from jconsole).
This approach works.
And as Konstantin earlier said it is because of different class loaders
that I can't do "new InitialContext()" during invocation from jconsole.
*My question is: how can I force it to use webapp classloader during new
InitialContext() while invoking from jconsole.*
is there a way to do something like
InitialContext.useClassLoader(webaappClassLoader)
?
During server startup InitialContext() used webapp classloader and during
invocation of mbean from jconsole it was some other classloader hence " new
InitialContext()" failed.
you got my question ?
Re: MBean InitialContext() Tomcat query- pls help
Posted by Pid * <pi...@pidster.com>.
On 27 Dec 2011, at 01:33, S B <sb...@gmail.com> wrote:
> On Mon, Dec 26, 2011 at 3:28 PM, Pid * <pi...@pidster.com> wrote:
>
>> On 26 Dec 2011, at 09:50, S B <sb...@gmail.com> wrote:
>>
>>> On Sat, Dec 24, 2011 at 6:29 PM, Pid <pi...@pidster.com> wrote:
>>>
>>>> On 23/12/2011 04:57, S B wrote:
>>>>> On Thu, Dec 22, 2011 at 8:49 PM, Pid <pi...@pidster.com> wrote:
>>>>>
>>>>>> On 22/12/2011 10:34, Konstantin Kolinko wrote:
>>>>>>> 2011/12/20 S B <sb...@gmail.com>:
>>>>>>>> Hi,
>>>>>>>>
>>>>>>>> I created and deployed an MBean in my tomcat. It uses datasource to
>>>>>> connect
>>>>>>>> to DB.
>>>>>>>>
>>>>>>>> My questions is:
>>>>>>>>
>>>>>>>> When I create InitialContext() inside MBean's constructor and pass
>> the
>>>>>>>> envContext to DBManager class to lookup datasource it works fine.
>>>>>> However
>>>>>>>> when I create InitialContext() in DBManager class, it fails.
>>>>>>>
>>>>>>> IIRC what InitialContext() sees as its environment highly depends on
>>>>>>> what classloader is active. That is TCCL =
>>>>>>> Thread.getContextClassLoader().
>>>>>>>
>>>>>>> So while it is run from within web application your TCCL = your
>>>>>>> webapp's classloader.
>>>>>>>
>>>>>>> When it is invoked from jconsole it might be a separate Thread, not
>>>>>>> related to your web application.
>>>>>>
>>>>>>
>>>>>> Like he ^^^ said. :)
>>>>>>
>>>>>>
>>>>>> p
>>>>>>
>>>>>>
>>>>>> --
>>>>>>
>>>>>> [key:62590808]
>>>>>>
>>>>>>
>>>>> Hi Pid/Konstantin,
>>>>>
>>>>> yes you are right. I just verified it. When it is invoked from
>> jconsole,
>>>>> the classloader is: sun.misc.Launcher$AppClassLoader@61e63e3d
>>>>> and when it is run within a web application the clasloader is
>>>>> WebAppClassloader.
>>>>>
>>>>> So, how can I force it to use webapp classloader during new
>>>>> InitialContext() while invoking from jconsole
>>>>> One possible way is to reuse the initialContext created during server
>>>>> startup. (pass it as param during invocation from jconsole).
>>>>>
>>>>> Is there a smarter way ??
>>>>
>>>> I am a bit concerned about how you are registering the bean inside the
>>>> bean's own constructor. I am not clear on how you are subsequently
>>>> unregistering that bean, before the reloading operation - and I am not
>>>> at all clear what the purpose of reloading is anyway.
>>>>
>>>> Is there a reason that the MBean itself needs to be recreated?
>>>>
>>>> Bear in mind that you are attempting to re-initialise the MBean, while
>>>> you are still using it. This does not seem like a good idea to me.
>>>>
>>>> I would suggest that you either have a separate Manager MBean that does
>>>> the reloading, or just have the reload method call the actual code on
>>>> the DB, without re-initialising the bean.
>>>>
>>>>
>>>> p
>>>>
>>>>
>>>> --
>>>>
>>>> [key:62590808]
>>>>
>>>>
>>> Hi,
>>>
>>> un-registering of mbean doesn't happen until servlet's destroy method is
>>> called.
>>> Actually, registration of bean happen only once, ie during server
>> startup.
>>> This time mbean's constructor is called and it is registered with MBean
>>> server.
>>> (I was wrong earlier when I said, constructor is called on each
>> invocation
>>> of reload() method from jconsole. sorry about that. i was lill confused.)
>>>
>>> MBean is never re-created. It is created only once and registered only
>> once.
>>>
>>> actual flow is:
>>>
>>> click reload() on jconsole gui.
>>> *it causes constructor of MBeanImpl to run. (verified from logs.)* --
>> *Wrong.
>>> pls disregard this statement.*
>>> calls reload() defined in MBeanImpl.
>>> calls DBManager.reload()
>>> inside DBManager.reload() it fails at InitialContext initContext = new
>>> InitialContext();
>>> the exception is - javax.naming.NoInitialContextException: Cannot
>>> instantiate class: org.apache.naming.java.javaURLContextFactory [Root
>>> exception is java.lang.ClassNotFoundException:
>>> org.apache.naming.java.javaURLContextFactory]
>>
>> OK, but what is the purpose of DBManager.reload()?
>>
>>
>> p
>>
>> ---------------------------------------------------------------------
>> To unsubscribe, e-mail: users-unsubscribe@tomcat.apache.org
>> For additional commands, e-mail: users-help@tomcat.apache.org
>>
>>
>
> Hi Pid, Marry Christmas !!!
> Purpose of DBManager.reload() is to load some application specific data
> from DB. Pls don't consider reload() as reload of MBean.
> reload() can better be renamed as loadData().
>
> when I invoke reload() from jconsole my application is suppose to make a db
> connection and load app specific data from database.
OK, so why not retain a reference to the DataSource that you're
getting the connection from?
p
---------------------------------------------------------------------
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For additional commands, e-mail: users-help@tomcat.apache.org
Re: MBean InitialContext() Tomcat query- pls help
Posted by S B <sb...@gmail.com>.
On Mon, Dec 26, 2011 at 3:28 PM, Pid * <pi...@pidster.com> wrote:
> On 26 Dec 2011, at 09:50, S B <sb...@gmail.com> wrote:
>
> > On Sat, Dec 24, 2011 at 6:29 PM, Pid <pi...@pidster.com> wrote:
> >
> >> On 23/12/2011 04:57, S B wrote:
> >>> On Thu, Dec 22, 2011 at 8:49 PM, Pid <pi...@pidster.com> wrote:
> >>>
> >>>> On 22/12/2011 10:34, Konstantin Kolinko wrote:
> >>>>> 2011/12/20 S B <sb...@gmail.com>:
> >>>>>> Hi,
> >>>>>>
> >>>>>> I created and deployed an MBean in my tomcat. It uses datasource to
> >>>> connect
> >>>>>> to DB.
> >>>>>>
> >>>>>> My questions is:
> >>>>>>
> >>>>>> When I create InitialContext() inside MBean's constructor and pass
> the
> >>>>>> envContext to DBManager class to lookup datasource it works fine.
> >>>> However
> >>>>>> when I create InitialContext() in DBManager class, it fails.
> >>>>>
> >>>>> IIRC what InitialContext() sees as its environment highly depends on
> >>>>> what classloader is active. That is TCCL =
> >>>>> Thread.getContextClassLoader().
> >>>>>
> >>>>> So while it is run from within web application your TCCL = your
> >>>>> webapp's classloader.
> >>>>>
> >>>>> When it is invoked from jconsole it might be a separate Thread, not
> >>>>> related to your web application.
> >>>>
> >>>>
> >>>> Like he ^^^ said. :)
> >>>>
> >>>>
> >>>> p
> >>>>
> >>>>
> >>>> --
> >>>>
> >>>> [key:62590808]
> >>>>
> >>>>
> >>> Hi Pid/Konstantin,
> >>>
> >>> yes you are right. I just verified it. When it is invoked from
> jconsole,
> >>> the classloader is: sun.misc.Launcher$AppClassLoader@61e63e3d
> >>> and when it is run within a web application the clasloader is
> >>> WebAppClassloader.
> >>>
> >>> So, how can I force it to use webapp classloader during new
> >>> InitialContext() while invoking from jconsole
> >>> One possible way is to reuse the initialContext created during server
> >>> startup. (pass it as param during invocation from jconsole).
> >>>
> >>> Is there a smarter way ??
> >>
> >> I am a bit concerned about how you are registering the bean inside the
> >> bean's own constructor. I am not clear on how you are subsequently
> >> unregistering that bean, before the reloading operation - and I am not
> >> at all clear what the purpose of reloading is anyway.
> >>
> >> Is there a reason that the MBean itself needs to be recreated?
> >>
> >> Bear in mind that you are attempting to re-initialise the MBean, while
> >> you are still using it. This does not seem like a good idea to me.
> >>
> >> I would suggest that you either have a separate Manager MBean that does
> >> the reloading, or just have the reload method call the actual code on
> >> the DB, without re-initialising the bean.
> >>
> >>
> >> p
> >>
> >>
> >> --
> >>
> >> [key:62590808]
> >>
> >>
> > Hi,
> >
> > un-registering of mbean doesn't happen until servlet's destroy method is
> > called.
> > Actually, registration of bean happen only once, ie during server
> startup.
> > This time mbean's constructor is called and it is registered with MBean
> > server.
> > (I was wrong earlier when I said, constructor is called on each
> invocation
> > of reload() method from jconsole. sorry about that. i was lill confused.)
> >
> > MBean is never re-created. It is created only once and registered only
> once.
> >
> > actual flow is:
> >
> > click reload() on jconsole gui.
> > *it causes constructor of MBeanImpl to run. (verified from logs.)* --
> *Wrong.
> > pls disregard this statement.*
> > calls reload() defined in MBeanImpl.
> > calls DBManager.reload()
> > inside DBManager.reload() it fails at InitialContext initContext = new
> > InitialContext();
> > the exception is - javax.naming.NoInitialContextException: Cannot
> > instantiate class: org.apache.naming.java.javaURLContextFactory [Root
> > exception is java.lang.ClassNotFoundException:
> > org.apache.naming.java.javaURLContextFactory]
>
> OK, but what is the purpose of DBManager.reload()?
>
>
> p
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: users-unsubscribe@tomcat.apache.org
> For additional commands, e-mail: users-help@tomcat.apache.org
>
>
Hi Pid, Marry Christmas !!!
Purpose of DBManager.reload() is to load some application specific data
from DB. Pls don't consider reload() as reload of MBean.
reload() can better be renamed as loadData().
when I invoke reload() from jconsole my application is suppose to make a db
connection and load app specific data from database.
Re: MBean InitialContext() Tomcat query- pls help
Posted by Pid * <pi...@pidster.com>.
On 26 Dec 2011, at 09:50, S B <sb...@gmail.com> wrote:
> On Sat, Dec 24, 2011 at 6:29 PM, Pid <pi...@pidster.com> wrote:
>
>> On 23/12/2011 04:57, S B wrote:
>>> On Thu, Dec 22, 2011 at 8:49 PM, Pid <pi...@pidster.com> wrote:
>>>
>>>> On 22/12/2011 10:34, Konstantin Kolinko wrote:
>>>>> 2011/12/20 S B <sb...@gmail.com>:
>>>>>> Hi,
>>>>>>
>>>>>> I created and deployed an MBean in my tomcat. It uses datasource to
>>>> connect
>>>>>> to DB.
>>>>>>
>>>>>> My questions is:
>>>>>>
>>>>>> When I create InitialContext() inside MBean's constructor and pass the
>>>>>> envContext to DBManager class to lookup datasource it works fine.
>>>> However
>>>>>> when I create InitialContext() in DBManager class, it fails.
>>>>>
>>>>> IIRC what InitialContext() sees as its environment highly depends on
>>>>> what classloader is active. That is TCCL =
>>>>> Thread.getContextClassLoader().
>>>>>
>>>>> So while it is run from within web application your TCCL = your
>>>>> webapp's classloader.
>>>>>
>>>>> When it is invoked from jconsole it might be a separate Thread, not
>>>>> related to your web application.
>>>>
>>>>
>>>> Like he ^^^ said. :)
>>>>
>>>>
>>>> p
>>>>
>>>>
>>>> --
>>>>
>>>> [key:62590808]
>>>>
>>>>
>>> Hi Pid/Konstantin,
>>>
>>> yes you are right. I just verified it. When it is invoked from jconsole,
>>> the classloader is: sun.misc.Launcher$AppClassLoader@61e63e3d
>>> and when it is run within a web application the clasloader is
>>> WebAppClassloader.
>>>
>>> So, how can I force it to use webapp classloader during new
>>> InitialContext() while invoking from jconsole
>>> One possible way is to reuse the initialContext created during server
>>> startup. (pass it as param during invocation from jconsole).
>>>
>>> Is there a smarter way ??
>>
>> I am a bit concerned about how you are registering the bean inside the
>> bean's own constructor. I am not clear on how you are subsequently
>> unregistering that bean, before the reloading operation - and I am not
>> at all clear what the purpose of reloading is anyway.
>>
>> Is there a reason that the MBean itself needs to be recreated?
>>
>> Bear in mind that you are attempting to re-initialise the MBean, while
>> you are still using it. This does not seem like a good idea to me.
>>
>> I would suggest that you either have a separate Manager MBean that does
>> the reloading, or just have the reload method call the actual code on
>> the DB, without re-initialising the bean.
>>
>>
>> p
>>
>>
>> --
>>
>> [key:62590808]
>>
>>
> Hi,
>
> un-registering of mbean doesn't happen until servlet's destroy method is
> called.
> Actually, registration of bean happen only once, ie during server startup.
> This time mbean's constructor is called and it is registered with MBean
> server.
> (I was wrong earlier when I said, constructor is called on each invocation
> of reload() method from jconsole. sorry about that. i was lill confused.)
>
> MBean is never re-created. It is created only once and registered only once.
>
> actual flow is:
>
> click reload() on jconsole gui.
> *it causes constructor of MBeanImpl to run. (verified from logs.)* -- *Wrong.
> pls disregard this statement.*
> calls reload() defined in MBeanImpl.
> calls DBManager.reload()
> inside DBManager.reload() it fails at InitialContext initContext = new
> InitialContext();
> the exception is - javax.naming.NoInitialContextException: Cannot
> instantiate class: org.apache.naming.java.javaURLContextFactory [Root
> exception is java.lang.ClassNotFoundException:
> org.apache.naming.java.javaURLContextFactory]
OK, but what is the purpose of DBManager.reload()?
p
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Re: MBean InitialContext() Tomcat query- pls help
Posted by S B <sb...@gmail.com>.
On Sat, Dec 24, 2011 at 6:29 PM, Pid <pi...@pidster.com> wrote:
> On 23/12/2011 04:57, S B wrote:
> > On Thu, Dec 22, 2011 at 8:49 PM, Pid <pi...@pidster.com> wrote:
> >
> >> On 22/12/2011 10:34, Konstantin Kolinko wrote:
> >>> 2011/12/20 S B <sb...@gmail.com>:
> >>>> Hi,
> >>>>
> >>>> I created and deployed an MBean in my tomcat. It uses datasource to
> >> connect
> >>>> to DB.
> >>>>
> >>>> My questions is:
> >>>>
> >>>> When I create InitialContext() inside MBean's constructor and pass the
> >>>> envContext to DBManager class to lookup datasource it works fine.
> >> However
> >>>> when I create InitialContext() in DBManager class, it fails.
> >>>
> >>> IIRC what InitialContext() sees as its environment highly depends on
> >>> what classloader is active. That is TCCL =
> >>> Thread.getContextClassLoader().
> >>>
> >>> So while it is run from within web application your TCCL = your
> >>> webapp's classloader.
> >>>
> >>> When it is invoked from jconsole it might be a separate Thread, not
> >>> related to your web application.
> >>
> >>
> >> Like he ^^^ said. :)
> >>
> >>
> >> p
> >>
> >>
> >> --
> >>
> >> [key:62590808]
> >>
> >>
> > Hi Pid/Konstantin,
> >
> > yes you are right. I just verified it. When it is invoked from jconsole,
> > the classloader is: sun.misc.Launcher$AppClassLoader@61e63e3d
> > and when it is run within a web application the clasloader is
> > WebAppClassloader.
> >
> > So, how can I force it to use webapp classloader during new
> > InitialContext() while invoking from jconsole
> > One possible way is to reuse the initialContext created during server
> > startup. (pass it as param during invocation from jconsole).
> >
> > Is there a smarter way ??
>
> I am a bit concerned about how you are registering the bean inside the
> bean's own constructor. I am not clear on how you are subsequently
> unregistering that bean, before the reloading operation - and I am not
> at all clear what the purpose of reloading is anyway.
>
> Is there a reason that the MBean itself needs to be recreated?
>
> Bear in mind that you are attempting to re-initialise the MBean, while
> you are still using it. This does not seem like a good idea to me.
>
> I would suggest that you either have a separate Manager MBean that does
> the reloading, or just have the reload method call the actual code on
> the DB, without re-initialising the bean.
>
>
> p
>
>
> --
>
> [key:62590808]
>
>
Hi,
un-registering of mbean doesn't happen until servlet's destroy method is
called.
Actually, registration of bean happen only once, ie during server startup.
This time mbean's constructor is called and it is registered with MBean
server.
(I was wrong earlier when I said, constructor is called on each invocation
of reload() method from jconsole. sorry about that. i was lill confused.)
MBean is never re-created. It is created only once and registered only once.
actual flow is:
click reload() on jconsole gui.
*it causes constructor of MBeanImpl to run. (verified from logs.)* -- *Wrong.
pls disregard this statement.*
calls reload() defined in MBeanImpl.
calls DBManager.reload()
inside DBManager.reload() it fails at InitialContext initContext = new
InitialContext();
the exception is - javax.naming.NoInitialContextException: Cannot
instantiate class: org.apache.naming.java.javaURLContextFactory [Root
exception is java.lang.ClassNotFoundException:
org.apache.naming.java.javaURLContextFactory]
Re: MBean InitialContext() Tomcat query- pls help
Posted by Pid <pi...@pidster.com>.
On 23/12/2011 04:57, S B wrote:
> On Thu, Dec 22, 2011 at 8:49 PM, Pid <pi...@pidster.com> wrote:
>
>> On 22/12/2011 10:34, Konstantin Kolinko wrote:
>>> 2011/12/20 S B <sb...@gmail.com>:
>>>> Hi,
>>>>
>>>> I created and deployed an MBean in my tomcat. It uses datasource to
>> connect
>>>> to DB.
>>>>
>>>> My questions is:
>>>>
>>>> When I create InitialContext() inside MBean's constructor and pass the
>>>> envContext to DBManager class to lookup datasource it works fine.
>> However
>>>> when I create InitialContext() in DBManager class, it fails.
>>>
>>> IIRC what InitialContext() sees as its environment highly depends on
>>> what classloader is active. That is TCCL =
>>> Thread.getContextClassLoader().
>>>
>>> So while it is run from within web application your TCCL = your
>>> webapp's classloader.
>>>
>>> When it is invoked from jconsole it might be a separate Thread, not
>>> related to your web application.
>>
>>
>> Like he ^^^ said. :)
>>
>>
>> p
>>
>>
>> --
>>
>> [key:62590808]
>>
>>
> Hi Pid/Konstantin,
>
> yes you are right. I just verified it. When it is invoked from jconsole,
> the classloader is: sun.misc.Launcher$AppClassLoader@61e63e3d
> and when it is run within a web application the clasloader is
> WebAppClassloader.
>
> So, how can I force it to use webapp classloader during new
> InitialContext() while invoking from jconsole
> One possible way is to reuse the initialContext created during server
> startup. (pass it as param during invocation from jconsole).
>
> Is there a smarter way ??
I am a bit concerned about how you are registering the bean inside the
bean's own constructor. I am not clear on how you are subsequently
unregistering that bean, before the reloading operation - and I am not
at all clear what the purpose of reloading is anyway.
Is there a reason that the MBean itself needs to be recreated?
Bear in mind that you are attempting to re-initialise the MBean, while
you are still using it. This does not seem like a good idea to me.
I would suggest that you either have a separate Manager MBean that does
the reloading, or just have the reload method call the actual code on
the DB, without re-initialising the bean.
p
--
[key:62590808]
Re: MBean InitialContext() Tomcat query- pls help
Posted by S B <sb...@gmail.com>.
On Thu, Dec 22, 2011 at 8:49 PM, Pid <pi...@pidster.com> wrote:
> On 22/12/2011 10:34, Konstantin Kolinko wrote:
> > 2011/12/20 S B <sb...@gmail.com>:
> >> Hi,
> >>
> >> I created and deployed an MBean in my tomcat. It uses datasource to
> connect
> >> to DB.
> >>
> >> My questions is:
> >>
> >> When I create InitialContext() inside MBean's constructor and pass the
> >> envContext to DBManager class to lookup datasource it works fine.
> However
> >> when I create InitialContext() in DBManager class, it fails.
> >
> > IIRC what InitialContext() sees as its environment highly depends on
> > what classloader is active. That is TCCL =
> > Thread.getContextClassLoader().
> >
> > So while it is run from within web application your TCCL = your
> > webapp's classloader.
> >
> > When it is invoked from jconsole it might be a separate Thread, not
> > related to your web application.
>
>
> Like he ^^^ said. :)
>
>
> p
>
>
> --
>
> [key:62590808]
>
>
Hi Pid/Konstantin,
yes you are right. I just verified it. When it is invoked from jconsole,
the classloader is: sun.misc.Launcher$AppClassLoader@61e63e3d
and when it is run within a web application the clasloader is
WebAppClassloader.
So, how can I force it to use webapp classloader during new
InitialContext() while invoking from jconsole
One possible way is to reuse the initialContext created during server
startup. (pass it as param during invocation from jconsole).
Is there a smarter way ??
Thanks,
Re: MBean InitialContext() Tomcat query- pls help
Posted by Pid <pi...@pidster.com>.
On 22/12/2011 10:34, Konstantin Kolinko wrote:
> 2011/12/20 S B <sb...@gmail.com>:
>> Hi,
>>
>> I created and deployed an MBean in my tomcat. It uses datasource to connect
>> to DB.
>>
>> My questions is:
>>
>> When I create InitialContext() inside MBean's constructor and pass the
>> envContext to DBManager class to lookup datasource it works fine. However
>> when I create InitialContext() in DBManager class, it fails.
>
> IIRC what InitialContext() sees as its environment highly depends on
> what classloader is active. That is TCCL =
> Thread.getContextClassLoader().
>
> So while it is run from within web application your TCCL = your
> webapp's classloader.
>
> When it is invoked from jconsole it might be a separate Thread, not
> related to your web application.
Like he ^^^ said. :)
p
--
[key:62590808]
Re: MBean InitialContext() Tomcat query- pls help
Posted by Konstantin Kolinko <kn...@gmail.com>.
2011/12/20 S B <sb...@gmail.com>:
> Hi,
>
> I created and deployed an MBean in my tomcat. It uses datasource to connect
> to DB.
>
> My questions is:
>
> When I create InitialContext() inside MBean's constructor and pass the
> envContext to DBManager class to lookup datasource it works fine. However
> when I create InitialContext() in DBManager class, it fails.
IIRC what InitialContext() sees as its environment highly depends on
what classloader is active. That is TCCL =
Thread.getContextClassLoader().
So while it is run from within web application your TCCL = your
webapp's classloader.
When it is invoked from jconsole it might be a separate Thread, not
related to your web application.
Best regards,
Konstantin Kolinko
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