Monthly Archives: March 2012

How to in Jdeveloper ADF Tutorials- Solve No JDBC Connection Error


If you happen to get the JDBC Connection error when you run the Application Module then make sure to check the adf-config.xml property jbo.SQLBuilder which should point to the correct database.

Also check the jbo.sql92.driverclass property for the AM Configuration to refer the class relevant to the DB

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Could not Deserialize the session data


Recently there was an issue with the session not getting invalidated upon logging out in adf page. we were using the following code to invalidate the session in the logout method


FacesContext fc = FacesContext.getCurrentInstance();
ExternalContext ec = fc.getExternalContext();
HttpServletRequest req = (HttpServletRequest) ec.getRequest();
HttpServletResponse res = (HttpServletResponse) ec.getResponse();
HttpSession ses = (HttpSession) req.getSession(false);
ses.invalidate();
res.sendRedirect(target);
fc.responseComplete();

with the above code the following exception was thrown to the user


java.lang.NullPointerException
 at oracle.adf.share.http.HttpUtil.getAttribute(HttpUtil.java:98)
 at oracle.adf.share.http.HttpSessionScopeAdapter.get(HttpSessionScopeAdapter.java:240)
 at oracle.jbo.common.ampool.SessionCookieImpl.<init>(SessionCookieImpl.java:164)
 at oracle.jbo.http.HttpSessionCookieImpl.<init>(HttpSessionCookieImpl.java:133)
 at oracle.jbo.http.HttpSessionCookieImpl.<init>(HttpSessionCookieImpl.java:124)
 at oracle.jbo.http.HttpSessionCookieFactory.createSessionCookie(HttpSessionCookieFactory.java:131)
 at oracle.jbo.common.ampool.ApplicationPoolImpl.createSessionCookie(ApplicationPoolImpl.java:452)
 at oracle.adf.model.bc4j.DataControlFactoryImpl.findOrCreateSessionCookie(DataControlFactoryImpl.java:141)
 at oracle.adf.model.bc4j.DataControlFactoryImpl.createSession(DataControlFactoryImpl.java:222)
 at oracle.adf.model.binding.DCDataControlReference.getDataControl(DCDataControlReference.java:76)
 at oracle.adf.model.BindingContext.get(BindingContext.java:457)
 at oracle.adf.model.binding.DCUtil.findSpelObject(DCUtil.java:280)
 at oracle.adf.model.binding.DCUtil.findSpelObject(DCUtil.java:248)
 at oracle.adf.model.binding.DCUtil.findContextObject(DCUtil.java:383)
 at oracle.adf.model.binding.DCIteratorBinding.<init>(DCIteratorBinding.java:127)
 at oracle.jbo.uicli.binding.JUIteratorBinding.<init>(JUIteratorBinding.java:60)

the issue is solved using the solution given in this forum
https://cn.forums.oracle.com/forums/thread.jspa?threadID=663589

ie. we have to release the Datacontrol also to invalidate the session

...
ValueBinding vb = fc.getCurrentInstance().getApplication().createValueBinding("#{data}");
BindingContext bc = (BindingContext)vb.getValue(fc.getCurrentInstance());
DataControl dc = bc.findDataControl("DataControl");
dc.release(DataControl.REL_ALL_REFS);
..

Iterative Development – Webcenter


Ho to enable Iterative Development in Web-center?

Iterative Development helps the developer to see the changes by just a refresh of the page in the integrated Server.

This makes the portal application development easy and rapid development.

Disadvantages of enabling this is that the application will run slowly as all the performance optimization settings will all be disabled. The ‘Delete Customization Before every run‘ is to be checked if we plan to enable the iterative Development option.

ADF Application Troubleshooting Flowchart – Explained


Initial Stage

Debugging the Issue:

Debugging the problem is the important step in finding the problem in ADF Application. If you are able to debug the application flow then there is a possible chance of pointing out the problem in the first place. Debugging help us to understand where and when the problem arises.

In ADF Application you can debug the issue by placing the breakpoints in Java class file and also in Task Flows. To know more about debugging follow this link

If we are able to identify the problem and fix it then its good. otherwise note down the problem and move to next step

Look for Errors:

After debugging the issues we are sure that the outcome will result in

  • What is the problem?
  • Where is the problem occurring?
  • When is the problem occurring?

Most of the time we have the exception thrown to the user or in the console. Its easy foe advanced user to identify the  cause of the issue when the exception or the error is thrown. Also the exceptions that occur will be self explanatory but its hard for newbie to spot the root cause.

Its always advised to find the exception or error for the clear understanding of the problem. So we have to find a way to get these exceptions thrown. These are the qualified places to look for errors and exceptions

  • JDeveloper Console – For integrated server
  • Weblogic Console – if its a standalone deployment

This link will help you to find the errors and also some standard practice to look for exceptions by preparing the application to log the application events using a Logger file.

After seeing the Exceptions

Search for Errors online

By this time you would have got the exception or the error in your hand. So don’t waste time start searching for the error in

  • To Search in Google efficiently follow this link
  • OTN Forum link is here
  • Documentation (11.1.1.6) link is here
  • Oracle Support link is here

Eg. If this is the error that you are getting


oracle.adf.controller.internal.AdfcIllegalStateException: oracle.adf.controller.ControllerException: ADFC-12003: The page flow scope stack is empty.
 at oracle.adfinternal.controller.state.PageFlowStackEntry.getPageFlowScope(PageFlowStackEntry.java:271)
 at oracle.adfinternal.controller.state.ViewPortContextImpl.getCurrentStateInstance(ViewPortContextImpl.java:594)
 at oracle.adfinternal.controller.state.RequestState.setCurrentViewPortContext(RequestState.java:200)
 at oracle.adfinternal.controller.state.ControllerState.setRequestState(ControllerState.java:948)
 at oracle.adfinternal.controller.state.ControllerState.synchronizeStatePart1(ControllerState.java:360)
 at oracle.adfinternal.controller.application.SyncNavigationStateListener.beforePhase(SyncNavigationStateListener.java:127)
 at oracle.adfinternal.controller.lifecycle.ADFLifecycleImpl$PagePhaseListenerWrapper.beforePhase(ADFLifecycleImpl.java:551)
 at oracle.adfinternal.controller.lifecycle.LifecycleImpl.internalDispatchBeforeEvent(LifecycleImpl.java:100)
 at oracle.adfinternal.controller.lifecycle.LifecycleImpl.dispatchBeforePagePhaseEvent(LifecycleImpl.java:147)
 at oracle.adfinternal.controller.faces.lifecycle.ADFPhaseListener$PhaseInvokerImpl.dispatchBeforePagePhaseEvent(ADFPhaseListener.java:112)
 at oracle.adfinternal.controller.faces.lifecycle.ADFPhaseListener.beforePhase(ADFPhaseListener.java:59)
 ...

Options to search

  1. oracle.adf.controller.internal.AdfcIllegalStateException (common search term)
  2. oracle.adf.controller.ControllerException (common search term)
  3. ADFC-12003: The page flow scope stack is empty (common search term)
  4. ADFC-12003  – you are widening the scope of the search if the above search term is not helping you
  5. oracle.adfinternal.controller.state.PageFlowStackEntry.getPageFlowScope – this will help you to identify when this problem arises
  6. PageFlowStackEntry.java:271 – strike the hammer at the point

Note: If you want to find issues similar to this in otn then give like ‘ADFC-12003 + OTN

Analysis Stage

You will come to this stage if you are not success with the above approach to identify the issue.

Are you trying some new Feature?

Is this a Connection Problem?

  • Check the connection, and make sure if you are able to connect to the DB properly.
  • Make sure that you have configured the Data Source properly.
  • Is the Databindings.cpx points to the correct application module configuration

Is it a common Java Issue?

  • Class path issue – Check if the libraries are there in the class path and if you have added the libraries to the project.
  • Did you add the correct libraries to the project
  • make sure that you ‘Deploy by Default‘ the libaries that you add
  • Common Exceptions – NullPointerException, ArithmeticException, NumberFormatingException etc
  • If these errors are shown inside the framework then check if you are doing what is expected and you are sure to check how it works.

Is this a common JEE Issue?

  • Deployment issue – this can be related to configurations in web.xml, weblogic.xml or weblogic-application.xml. Check if this can be solved using the parameters, filters or servlet mapping in web.xml
  • Session related issue – This can be again related to web.xml and session handling
  • Transaction issue – configurations related to adfc-config.xml

Configuration Issue?

  • All configuration parameters are here

Page Refresh Issue?

  • Check iterator refresh condition property
  • Check the changeeventpolicy in iterator
  • is the partialsubmit or the autosubmit is working as expected
  • cross check with the immediate property
  • Check the partial triggers property

Security Issue?

  • May be related to jazn-data.xml, is the system-data.xml getting updated with the User and Roles
  • the configurations are done in web.xml, weblogic.xml
  • Check security settings in weblogic server.
  • Check security setting for the folders also, sometimes the server needs full permission for some updates. This may also cause some problem

Intermittent Issue?

  • This may be related to Clustering. Cross check with clustering of ADF Application
  • adf-config.xml has some property for clustering. check that

Memory Issue?

  • Increase the Heap size for the application and try
  • make your application more performance to overcome any memory issues

Data Issue?

  • Check if the DB data is proper
  • Run the query in the back end to make sure that you get the proper result

Change not reflecting?

  • Do a clean build and try to run again. make sure you generate the classes again
  • remove drs folder in system folder or remove the DefaultDomain folder or remove the complete system folder and try from scratch

Not sure about the problem?

  • Cross check our logic,never assume that your logic is correct, try to alter the logic ,ask your peer to review the logic (others will have an extra eye on the problem and the approach)
  • Read the Documentation again to check how the component works and make sure that you completely understand it

Note: Most of the issues listed above are common issues, you will get all related issues when you search online or in Oracle Forums. I believe that Only 5% of the issues can be considered as never experienced by others. So most of the issues that the user experience will be already discussed in the future. So do search the Oracle forums or Google to get your issues solved.

Submission Stage

Post a Forum Question

  • This stage is like you are asking for help from the experts who has some expertise in the area.
  • Wait for the answers, if you are not getting an answer ask for it again one or two times
  • If someone post for your question then try to validate that. Don’t ignore if someone who is not an expert replied to our post. Its better to try all possible ways.
  • If you get an answer, try that and update the post about your findings even if the issue is fixed. This will help some other person who is facing similar issue like you

Raise for help from Oracle

If you have tried all possible options above then you have to wait for Oracle to help you.

  • Raise an SR

ADF Resources and Learning


ADF Resources to learn
https://blogs.oracle.com/shay/entry/how_do_i_start_learning_oracle_adf_and_jdeveloper
also
http://download.oracle.com/tutorials/jtcd3/ecourse_adf_part1/html/temp_frameset/index.htm
http://www.oracle.com/technetwork/indexes/samplecode/index.html
http://docs.oracle.com/cd/E18941_01/tutorials/toc.htm
http://www.oracle.com/technetwork/developer-tools/jdev/overview/index.html

Stop Blog Theft !!!


This is to inform that Mr. Saravanan of http://jdeveloperandadf.blogspot.com is stealing many blog contents without prior permission of the original authors. I am the victim along with others.

So I believe that all his blogs are stolen from some other blogs..

Blog date May 4, 2010
https://vtkrishn.com/2010/05/04/how-normal-jar-library-is-different-from-adf-library/
Stealing date Sunday, May 15, 2011
http://jdeveloperandadf.blogspot.com/2011/05/how-normal-jar-library-is-different.html#comment-form

http://www.techartifact.com/blogs/2011/08/oracle-adf-interview-question-part-2.html
Stealing date Tuesday, February 15, 2011
http://jdeveloperandadf.blogspot.com/2011/02/oracle-adf-interview-questions-and.html

Blog date Tuesday, March 29, 2011
http://shidharth.blogspot.com/2011/03/floating-footer-page-layout-in-adf.html
Stealing date Sunday, April 3, 2011
http://jdeveloperandadf.blogspot.com/2011/04/floating-footer-page-layout-in-adf.html

Blog date Wednesday, February 24, 2010
http://sameh-nassar.blogspot.com/2010/02/javascript-functions-sample.html
Stealing date Thursday, March 3, 2011
http://jdeveloperandadf.blogspot.com/2011/03/javascript-with-adf-faces-samples.html

(In this the link that he mention’s goes to Andrejus’s Blog – caught red handed)
Blog date Sunday, February 13, 2011
http://andrejusb.blogspot.com/2011/02/adf-region-communication-region-refresh.html
Stealing date Saturday, March 5, 2011
http://jdeveloperandadf.blogspot.com/2011/03/adf-region-communication-region-refresh.html

So BEWARE of this guy..

Nic tool to keep multiple terminal sessions – Pedorosa


Recently I got to know this tool from my colleague to keep track of multiple terminal sessions under a single view.

For example, imagine you are working on multiple server session and you want to keep track of the session or the server running. search for the log files, tailing log outputs then we will open n number of putty terminals to connect to the server or telnet multiple windows. But how will this be organized under one single window?

That where the software Pedorasa come into picture.

The screenshot of the sample is

you can download this free tool from here