How to understand EJB and JSP

just now i read some articles about EJB and it make me a little confused in what i have understood about EJB and JSP ( at least i thought i understood them, but now ....()
1. i found that in most JSP examples, the javabeans are used but not the EJB, right? so i have a qustion, an EJB can be used in JSP or not? and how if it can? why if it can not?
...still have a lot of question ....
thanks a lot

Hi,
1. i found that in most JSP examples, the javabeans
are used but not the EJB, right? so i have a qustion,
an EJB can be used in JSP or not? and how if it can?
why if it can not?It can be there for more of the examples,but you can invoke the EJB from the JSP also .Actual EJB is entirely the different concept whose foundation is build on the Distributed Technology.I advice you to read the Mastering EJB which is freely available at http://theserverside.com
before starting coding.The EJB is a vast concept and requires time and strong core foundation to understand,once it is clear then you understand it true potential...
...still have a lot of question ....You queries are welcome here!!!
regards
Vicky

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try this...as a test..
take a simple Contact ejb (as simple as you can make it, just a name and email address). In the ejb-jar.xml set up a role, for example, user, and restrict the access to only this role for all methods.
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hello,
i am novice programmer in EJB.
i am using weblogic 6.1 ...
my problem is how to use EJB in jsp page.
my code is as follow..but its not displaying any result.
<%@ page import="javax.naming.InitialContext,
javax.naming.Context,
java.util.Properties,
firstEJB.First,
firstEJB.FirstHome"%>
<%
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     p.put(Context.INITIAL_CONTEXT_FACTORY,"weblogic.jndi.TengahInitialContextFactory");
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%>
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javax.servlet.RequestDispatcher dispatcher = getServletContext().getRequestDispatcher(�/Ashu.jsp�);
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How to understand Credit and Debit account.....

Hi,
As an SD consultant, what's your understanding on Credit and Debit those FI terms.
Like Sales revene or Sales return scenario...
How those process interacted with Credit and Debit...
Thanks.

Accounting Principle is lad down on Golden Rule as under:
Personal Account:
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Credit - The Giver
Real Account:
Debit - What Comes In
Credit - What Goes Out
Nominal account:
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Credit - All Income and Gains
To illustrate with Example:
When We raise an Invoice to Customer, the Accounting Entry is as under:
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To Sales..........................Credit
To Taxes..........................Credit
In SAP, Based on Mapping of G/l Account in T.code: VKOA and OB40, relevant G/L account are triggered. G/L accounts as disigned such that it would take cage of Debit and Credit, if mapping is correct in T.code: VKOA and OB40.
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How to run EJB with JSP as client on TOMCAT - JBOSS server

Hi all,
I am having my EJB component successfully deployed on JBOSS server. My core-java client is able to access the same. But when I use the JSP page which is on Tomcat server, I am getting following exception. Please help me out.
Exception Report:
org.apache.jasper.JasperException: sealing violation
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     at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:407)
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     at org.apache.catalina.connector.http.HttpProcessor.process(HttpProcessor.java:818)
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Root Cause:
java.lang.SecurityException: sealing violation
     at java.net.URLClassLoader.defineClass(URLClassLoader.java:234)
     at java.net.URLClassLoader.access$100(URLClassLoader.java:56)
     at java.net.URLClassLoader$1.run(URLClassLoader.java:195)
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     at org.apache.jasper.servlet.JasperLoader.loadClass(JasperLoader.java:136)
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     at java.lang.Class.newInstance0(Native Method)
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     at org.apache.jasper.servlet.JspServlet$JspServletWrapper.loadIfNecessary(JspServlet.java:161)
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     at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:977)
     at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:196)
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     at org.apache.catalina.core.StandardContext.invoke(StandardContext.java:2041)
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     at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:977)
     at org.apache.catalina.connector.http.HttpProcessor.process(HttpProcessor.java:818)
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Please let me know what the problem is as I am new to EJB.
Thanx a lot
Unmesh

Hi
Even i have the same problem...
i have deployed the ejb in jboss..
but i cannot even run the core-java client program
can u pls mail me the code...
and the directory path
thanks a lot
cheers
simreen

How to connect EJB by JSP??

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Hi,everyone,I hava found out its anwsers.
The method :
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CODE:
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InitialContext ctx=new InitialConrect();
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HappyHome hoppyhome;
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%>
WELCOME FOR YOUE ADVISE!!!

EJBs and JSPs error

Hi!
I'm deploying a new application using the deploy tool from J2SDKEEE1.2.1.
It has a bean (Entity CMP Bean) called Product (ProductEJB, ProductHome, Product) which works if I test it with a console-based client.
My problem is that I want to query it using a JSP. I don't want to use JavaBeans (<jsp:useBean...) and write the simple code straight to the .jsp file.
But the JSP, when getting compiled on the server, is unable to find the Product and ProductHome classes needed in the code.
I tried to put these in WEB-INF/classes but it still won't work.
I'm pretty new at this EJB stuff (I'm a Resin user). Please help!
THX!

Make sure your import-statements include the package where the classes reside.

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I have an EJB (called Vault) which (apart from all the essential stuff) contains only:
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This is a simplified version of code that was presenting a similar problem; on re-pressing a button, old data was being displayed.
HTML/JSP code below.
Any insights would be greatly appreciated.
John
Frame page defines javascript for three buttons:
<HTML>
<HEAD>
<TITLE>Vault</TITLE>
<SCRIPT LANGUAGE="JavaScript">

</SCRIPT>
</HEAD>
<FRAMESET onLoad="initialize()" FRAMEBORDER="0" FRAMESPACING="0"
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<FRAME SRC="Browse.html" NAME="treeFrame">
</FRAMESET>
</HTML>
Initial page Browse.html
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<HEAD>
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</HEAD>
<BODY>
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<INPUT TYPE=BUTTON OnClick="javascript:top.two()" VALUE="2">
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</BODY>
</HTML>
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<HEAD>
<TITLE>DisplayData</TITLE>
<SCRIPT LANGUAGE="JavaScript">
</SCRIPT>
</HEAD>
<BODY>
<%!
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%>
<form>
<INPUT TYPE=BUTTON OnClick="javascript:top.one()" VALUE="1">
<INPUT TYPE=BUTTON OnClick="javascript:top.two()" VALUE="2">
<INPUT TYPE=BUTTON OnClick="javascript:top.three()" VALUE="3">
</form>
<%
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%>
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This is not an EJB problem as I thought, as I can duplicate it with a
normal Java class called from JSP page; in fact its an IE special
feature. It works fine under Netscape, and only shows the offending
behaviour under IE (thank you again Micros**t). So its back to
Netscape as standard for me!
John

How to understand EJB and JSP

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