When to use ApplicationBean and Session Bean dataproviders

hi i am developing a small application, in which i have cached rowset and if i want to access the database i have to call the bean component so which one to call either application Bean or Session Bean component in some examples they used application bean and in some applications they used session bean. Please suggest me the right one and i have to access the database correctly. I am confused ,please help me out in solving this problem.
Thanking You in Advance.

The following excerpt is from http://developers.sun.com/prodtech/javatools/jscreator/learning/tutorials/2/scopes.html
Before you create a bean property to store a value, you must decide what scope to put the property in. Because several users can access a web application at the same time, you want to use the smallest scope possible so that you don't waste valuable space. The following figure illustrates the duration of each type of scope.
* Application scope lasts until the server stops the application. Values that you store in an application bean are available to every session and every request that uses the same application map.
* Session scope begins when a user first accesses a page in the web application and ends when the session times out due to inactivity, or when the web application invalidates the session, such as, for example, by calling session.invalidate().
* Request scope begins when the user submits the page and ends when the response is fully rendered, whatever page that is.

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When to use Custom Adapter, Event Beans and Spring beans

Hi,
I have basic question on when or on what basis/scenario the Custom Adapter, Event Beans or Spring beans should be used.
All three has same implementation methods.
Please help me in understanding when to use Custom Adapters, Event Beans or Spring beans.
Thanks,
Sri
Edited by: 897694 on Mar 7, 2012 8:12 AM

custom adapters:
you have to use a custom adapter when you don't find any adapter in ocep which will serve your purpose.
Most of the times you use an adapter to connect the application with external things like http server, etc It can be both to listen the events or to send the events outside.
Event Beans:
This type of beans does most of the work that an adapter code does but in convention beans are not used to connect the application with external stuff
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If you implement Interfaces like Initializing Bean for an adapter code it won't work properly, you have to use an event Bean in that case.
Spring beans:
Spring beans are used when the bean code doesn't implement EventSink or EventSender.
These beans are used to enable something (eg: make ${wlevs_dev_home}/abc/a/b.java this path is not understandable by java code unless you override the path using a spring bean)
Most of the things which doesn't need a connection between components in the application (eg cache loader: you can do this using spring beans and event beans both but spring beans doesn't need a connection with cache)
Hope this small writeup helps you :)
Edited by: Patha on Mar 8, 2012 9:10 AM

Entity Beans and Session beans to represet Business lOgic

How cam we implement Entity Beans and Session beans to represent Business Logic.
Can anyone explain how can we do this.
Regards...

I have session beans calling method in entity beans and any client
doesn't have access to entity beans, only via session beans.
If i define security policy and method permissions for session beans
only, do entity beans use that permissions when calling their methods
from sessions beans OR should i define the security policy for entity
beans separately?If you want to set the permission on individual
methods of entity bean ( with different roles)
you have to do it separately.
If you want to delegate the Authenticated user along with
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For more detail please check out the EJB2.0 Spec.
-utpal

Error when returning Vector from EJB Session Bean

I am testing the EJB functionality within JDeveloper(9.0.3). I simply expanded on the tutorial that is in the documentation (departments and employees). I created a method in the stateless session bean that retrieves a Collection of employees for a department, then converts it to a Vector. When I try to return the Vector from the session bean to a sample client, I get an error indicating that the Object is NOT serializable. I know that Vector IS serializable. Why do I get this error? (The error displays on the client message log, NOT the OC4J message log). I tried dumping the Vector to System.out.println - this works fine, so I l know I'm getting data.
Here is the stack trace and errors that display:
com.evermind.server.rmi.OrionRemoteException: Error (de-)serializing object: EmployeeLocal_EntityBeanWrapper4
     java.lang.Object com.evermind.server.ejb.EJBUtils.cloneSerialize(java.lang.Object, com.evermind.server.ejb.AbstractEJBHome)
          EJBUtils.java:404
     java.lang.Object com.evermind.server.ejb.EJBUtils.cloneObject(java.lang.Object, com.evermind.server.ejb.AbstractEJBHome)
          EJBUtils.java:377
     java.lang.Object com.evermind.server.ejb.EJBUtils.cloneOneObjectInstance(java.lang.Object, com.evermind.server.ejb.AbstractEJBHome)
          EJBUtils.java:419
     java.lang.Object com.evermind.server.ejb.EJBUtils.cloneArrayList(java.util.ArrayList, com.evermind.server.ejb.AbstractEJBHome)
          EJBUtils.java:599
     java.lang.Object com.evermind.server.ejb.EJBUtils.cloneObject(java.lang.Object, com.evermind.server.ejb.AbstractEJBHome)
          EJBUtils.java:357
     java.util.Collection hrApp_StatelessSessionBeanWrapper2.getEmployeesByDepartment(java.lang.Long)
          hrApp_StatelessSessionBeanWrapper2.java:323
     java.lang.Object java.lang.reflect.Method.invoke(java.lang.Object, java.lang.Object[])
          native code
     void com.evermind.server.rmi.RMICallHandler.run(java.lang.Thread)
          RMICallHandler.java:119
     void com.evermind.server.rmi.RMICallHandler.run()
          RMICallHandler.java:48
     void EDU.oswego.cs.dl.util.concurrent.PooledExecutor$Worker.run()
          PooledExecutor.java:803
     void java.lang.Thread.run()
          Thread.java:484
at connection to localhost/127.0.0.1 as admin
     void com.evermind.server.rmi.RMIConnection.EXCEPTION_ORIGINATES_FROM_THE_REMOTE_SERVER(java.lang.Throwable)
          RMIConnection.java:1558
     java.lang.Object com.evermind.server.rmi.RMIConnection.invokeMethod(com.evermind.server.rmi.RMIContext, long, long, java.lang.reflect.Method, java.lang.Object[])
          RMIConnection.java:1511
     java.lang.Object com.evermind.server.rmi.RemoteInvocationHandler.invoke(java.lang.Object, java.lang.reflect.Method, java.lang.Object[])
          RemoteInvocationHandler.java:53
     java.lang.Object com.evermind.server.rmi.RecoverableRemoteInvocationHandler.invoke(java.lang.Object, java.lang.reflect.Method, java.lang.Object[])
          RecoverableRemoteInvocationHandler.java:22
     java.lang.Object com.evermind.server.ejb.StatelessSessionRemoteInvocationHandler.invoke(java.lang.Object, java.lang.reflect.Method, java.lang.Object[])
          StatelessSessionRemoteInvocationHandler.java:50
     java.util.Collection __Proxy1.getEmployeesByDepartment(java.lang.Long)
     javax.swing.table.DefaultTableModel hr.hrAppClientFrame.getTableModel()
          hrAppClientFrame.java:150
     void hr.hrAppClientFrame.jbInit()
          hrAppClientFrame.java:122
     void hr.hrAppClientFrame.<init>()
          hrAppClientFrame.java:58
     void hr.hrAppClientFrame.main(java.lang.String[])
          hrAppClientFrame.java:141
     Nested exception is:
java.io.NotSerializableException: EmployeeLocal_EntityBeanWrapper4
     void java.io.ObjectOutputStream.outputObject(java.lang.Object)
          ObjectOutputStream.java:1148
     void java.io.ObjectOutputStream.writeObject(java.lang.Object)
          ObjectOutputStream.java:366
     java.lang.Object com.evermind.server.ejb.EJBUtils.cloneSerialize(java.lang.Object, com.evermind.server.ejb.AbstractEJBHome)
          EJBUtils.java:390
     java.lang.Object com.evermind.server.ejb.EJBUtils.cloneObject(java.lang.Object, com.evermind.server.ejb.AbstractEJBHome)
          EJBUtils.java:377
     java.lang.Object com.evermind.server.ejb.EJBUtils.cloneOneObjectInstance(java.lang.Object, com.evermind.server.ejb.AbstractEJBHome)
          EJBUtils.java:419
     java.lang.Object com.evermind.server.ejb.EJBUtils.cloneArrayList(java.util.ArrayList, com.evermind.server.ejb.AbstractEJBHome)
          EJBUtils.java:599
     java.lang.Object com.evermind.server.ejb.EJBUtils.cloneObject(java.lang.Object, com.evermind.server.ejb.AbstractEJBHome)
          EJBUtils.java:357
     java.util.Collection hrApp_StatelessSessionBeanWrapper2.getEmployeesByDepartment(java.lang.Long)
          hrApp_StatelessSessionBeanWrapper2.java:323
     java.lang.Object java.lang.reflect.Method.invoke(java.lang.Object, java.lang.Object[])
          native code
     void com.evermind.server.rmi.RMICallHandler.run(java.lang.Thread)
          RMICallHandler.java:119
     void com.evermind.server.rmi.RMICallHandler.run()
          RMICallHandler.java:48
     void EDU.oswego.cs.dl.util.concurrent.PooledExecutor$Worker.run()
          PooledExecutor.java:803
     void java.lang.Thread.run()
          Thread.java:484
at connection to localhost/127.0.0.1
     void com.evermind.server.rmi.OrionRemoteException.receive(java.net.InetAddress, java.lang.String)
          OrionRemoteException.java:130
     void com.evermind.server.rmi.RMIConnection.handleMethodInvocationResponse()
          RMIConnection.java:1673
     void com.evermind.server.rmi.RMIConnection.run(java.lang.Thread)
          RMIConnection.java:532
     void com.evermind.server.rmi.RMIConnection.run()
          RMIConnection.java:275
     void EDU.oswego.cs.dl.util.concurrent.PooledExecutor$Worker.run()
          PooledExecutor.java:797
     void java.lang.Thread.run()
          Thread.java:484
Any ideas?
Thanks

I would suggest opening a case with [email protected] FWIW, I recall seeing
          something like this in WLS 6.0. I believe it is fixed in WLS 6.1
          -- Rob
          Chris Dupuy wrote:
          > Btw, this occurs when I create an stateful session bean that ends up
          > throwing an exception and setRollbackOnly() is called. From that point
          > forward, my logs fill with this message.
          >
          > Chris
          >
          > "Chris Dupuy" <[email protected]> wrote in message
          > news:[email protected]..
          > > anyone know what this means, and what you can do about it?
          > >
          > >
          > > <Error> <ConnectionManager> <atossd03> <cbeyondServer> <ExecuteThread:
          > '14'
          > > for queue: 'd
          > > efault'> <> <> <000000> <Closing:
          > 'weblogic.rjvm.t3.T3JVMConnection@488831'
          > > because of: 'Server received a message over an uniniti
          > > alized connection: 'JVMMessage from: 'null' to:
          > >
          > '5825313123619479267S:10.6.6.40:[8000,8000,8001,8001,8000,8001,-1]:cbeyond:c
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          > > Server' cmd: 'CMD_REQUEST', QOS: '101', responseId: '2', invokableId: '1',
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          > > ffset: '204'''>
          > >
          > >
          > >

When I use Mail and want to paste an emailadress with a right mouse click in the adres field this doesn't work, ofcourse cmd V works. How can I solve this

when I use Mail and want to paste an emailadress with a right mouse click in the adres field this doesn't work, ofcourse cmd V works. How can I solve this

YAY! That did it.
Thank you so much.
And a Very Happy and Prosperous New Year to you!
bonnie

When to use inheritance and when not to?

I've just been trying find out when to use inheritance and when not to use inheritance? I know that inheritance gives advantages such as code reuse and maintainability. But when are their times not to use inheritance that may effect the design of a project?
Also when should one consider aggregation over inheritance(is-a relationship)?
thanks,
plandis

Hi
Answering this question usually requires a few books, so, I'm sorry, it's not really as simple as choosing between using a screwdriver vs. a hammer.
But, very short, inheritance should ideally only be used when there exist a strict 'is-a' relationship. However, sometimes it may be clever to inherit when you have a 'is-almost-a' relationship... And sometimes this is a stupid move. This depends on the context/circumstances.
Aggregation is normally considered a 'has-a' relationship, thereby differing clearly from inheritance. The old 'car' model says "a car is-a vehicle and has-some (at least) wheels."
The wheels are aggregated to the car class, that itself is inherited from vehicle.
However, this is just a good rule-of-thumb and there may be circumstantial reasons for not following these guidelines.

When to use SELECT and END SELECT in the query.

hi all,
When to use SELECT and END SELECT in the query.
regads,
Venkata Suresh Penke.

Hi Suresh..
When do we need to use SELECT .. ENDSELECT
Usually we will never use SELECT .. ENDSELECT as it gives very poor performance.
But whenever we read a single Record we will use it as an alternative for SELECT SINGLE in some scenarios.
Eg: When the Full primary key is not specified in the WHERE clause.
SELECT * FROM MARC INTO WA_MARC UP TO 1 ROWS WHERE MATNR = P_MATNR.
ENDSELECT.
And other scenario is when we perform AGGREGATE OPERATIONS.when the Result is only one row.
SELECT SUM( LABST ) FROM MARD INTO V_LABST UP TO 1 ROWS
WHERE MATNR = P_MATNR.
ENDSELECT.
Note: In The Above scenario we cannot use SELECT SINGLE..
<b>REWARD IF HELPFUL.</b>

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Summary:
========
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Using EJB remote session beans llike webservice.

My requirement is to fetch a big size ASCII stream file from a remote location. For this can I use Statless EJB Session beans?
For this EJB application & Web application will be on my application server side & EJB client should reside on the remote end side from where I want to fetch the file. - Please confirm my this logic as I am new in Java & EJB, I am having a basic query like this. (I don't want to proceed with EJB web service like (@Stateless, @WebService), I want to purly use EJB Statless Remote session beans - Is this possible?
If yes, can I have one sample example URL pls?
Thanks in advance for your help.

My requirement is to fetch a big size ASCII stream file from a remote location. For this can I use Statless EJB Session beans?
For this EJB application & Web application will be on my application server side & EJB client should reside on the remote end side from where I want to fetch the file. - Please confirm my this logic as I am new in Java & EJB, I am having a basic query like this. (I don't want to proceed with EJB web service like (@Stateless, @WebService), I want to purly use EJB Statless Remote session beans - Is this possible?
If yes, can I have one sample example URL pls?
Thanks in advance for your help.

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* http://forums.spybot.info/
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Hi,
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is there any software problems ??

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WHEN TO USE SYS_REFCURSOR AND WHEN NOT TO USE REFCURSOR

SYS_REFCURSOR is a Weakly Defined Cursor
DECLARE emp_refcur SYS_REFCURSOR;
when this is so simple
why this
DECLARE TYPE emp_cur_type IS REF CURSOR RETURN emp%ROWTYPE; my_rec emp_cur_type; ?
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> WHEN TO USE SYS_REFCURSOR AND WHEN NOT TO USE REFCURSOR
When the requirements define that one is better suited than the other.
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2) PL applies the back-end server logic and construct a SQL statement for the client.
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Advantages.
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So my response is "so what?" - it is more important to *correctly" chose what type of client cursor data type you want to use to interact with the back-end SQL cursor. Once that decision has been made (based on technical sound logic), then one can look at (minor) issues such as weak vs. strong ref cursors.

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You might look at "Keyboard Shortcuts" in the Keyboard and Mouse preference pane and see if somehow the lower case n has been inadvertently assigned to something.
Probably the best solution would be to click the "Restore Defaults" button.

My iphone 4s keeps freezing up. I have restored it as a new phone. Done numerous resets. But it still keeps freezing up when im using apps and trying to text. Its really annoying.

My iphone 4s keeps freezing up. I have restored it as a new phone. Done numerous resets. But it still keeps freezing up when im using apps and trying to text. Its really annoying.

Oh OisinC7,
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When to use ApplicationBean and Session Bean dataproviders

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