EJB / EE :: Session Bean Must Not Extend Another Session Bean?
Nov 9, 2014
I have tried this example ([URL].../) with CarDao extending the BaseDao, it works like a charm.However, from the CarDao class, my NetBeans underlined the class name “CarDao” with the error message “A session bean must not extend another session bean.” But I can compile, deploy and run the application without any problem.
I have also heard that a session bean cannot extend another session bean, but why it works here?
I am using Java EE 6, NetBeans 8.0.1 and WebLogic 12c for this code testing.
But resource.returnString(r); gives a org.apache.jasper.JasperException: java.lang.NullPointerException I started the glassfish server in debug mode and found out that "resource" was null. but @PostConstruct in singleton does print which means singleton bean exists.
Can we call singleton beans with no interface in such a way form a session bean? I actually want to acquire instance of singleton bean when a client invokes method in Client bean...
When i create an application Bean how i can update it from another bean? Lets say application Bean has variable h=1 and i want to update from another bean and make it 2 how i can do it? And how i can access the value of a session bean from another bean?
In stateful session bean client servlet we are explicitly setting shoppingCart to session attribute. I do not remember doing similar step withStatelessSession bean.
In my case my managed bean is View Scoped and it supports a UI page which has multiple forms and each form is submitted as AJAX POST request.
As per the statndard, setting restriction to 5 should create 5 views and after that based on LRU algorithm the oldest views should get deleted if 6th views is created.
Therefore any action on the oldest view will throw the ViewExpiredException and i simply redirect the user to view expired page.
1) When i set the restriction to 5 views, i open 4 tabs with 3 forms each. 2) I submit the 3 forms on first tab everything works fine. 3) As soon as I go to 2nd tab and submit the first form thr, i get view expired exception 4) It seems I am exceeding the number of views I mentioned in web.xml
I want to know :
1) Does every AJAX POST submit itself creates a view ? 2) How I can count the number of views created in a session ? 3)Can i force expiry of a view in JSF 2.0.2 while the session is still alive ? 4) Normally JSF 2.0.2 session cachces the views. Lets assume session is alive the entire day but a view was created in morning at 9:00 AM and is not used again the entire day. Assuming that session doesn't reaches the max number of views it can save in entire day, will the view created in morning expire on its own after certain interval of time ? If not , can we still force its expiry while keeping the session alive ?
I read JEE6 doc and confused with : Does container managed entity manager (injected by PersistenceContext annotation) is thread-safe in stateless session bean in multiple-thread env?
See code below, if there are 2 requests to stateless sesion bean in 2 concurrent threads , is it using same Entity Manager Instance or not?
@Stateless(name = "HRFacade", mappedName = "HR_FACES_EJB_JPA-HRFacade-HRFacade") public class HRFacadeBean implements HRFacade, HRFacadeLocal { @Resource SessionContext sessionContext;
I'm new to JSP but I've to use it to grab data coming from an external site, pass data to a Bean, write data in a DB and redirect the user to another page. Follow the JSP page.
<%@page import="EJB.getResponse"%> <% long paymentID = Long.parseLong(request.getParameter("paymentid")); String responsecode = "9999"; getResponse g = new getResponse();
[Code] ....
This is the bean:
@ManagedBean @RequestScoped public class getResponse implements Serializable { private Long paymentId; private String result; private String auth;
[Code] ....
On the console I see the prints but I receive the NullPointerException
WARNING: StandardWrapperValve[jsp]: PWC1406: Servlet.service() for servlet jsp threw exception java.lang.NullPointerException at EJB.getResponse.printData(getResponse.java:72) at org.apache.jsp.notify_jsp._jspService(notify_jsp.java from :60) at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:111)
May be I did not understand the meaning and usage of attribute "session" in page directive. My understanding is if session=false, in page directive, then the JSP page will not participate in the session. However, I have my welcomepage as below:
Can I access the session object even session has been expired? I need to check whether session is expired or not for each request.The session invalidation is set null the session object. What I concluded, session time out I can access session object but session invalidation I can not access session object. How can I find the session time out by using session object?
1) From War A, I login to the application and then fetch some users that is a rest call. I get the response back from rest in json form that ui consumes and display the data on page.
2) Now I click on the logout link from ui jsp. This logs out the session from Ui. I use <form data-dojo-type="dijit/form/Form" based logout.
3) I then go to the proxy (using burp) and manually request the rest call which I made in step no 1), the rest gives the response back with the same json object returned in step no 1) This shows that the logout action on step 2) is invalidated the session from War A (ui war) but the session or cookie based from WAR B (rest war) is not invalidated.
Expected outcome:After I Logout from War A(ui war), the session must also get invalidated from war B (rest war) and manually request from proxy should not get the same response object as received in step 1)
I am developing a e-commerce college project, here i add the items in the cart(a div tag in the jsp page) via servlet by creating sessions,
flow control: shopping jsp (when user wants to add an item in the cart) --> item servlet (which is used to create session and synchronized it) --> cart servlet(which is used to add items in the arraylist and show them in the shopping.jsp's div tag + it also sets the total purchase amount in the session variable "totalpurchase")
now after that user wants to proceed to checkout, here i use the onclick event to check the minimumshopping amount must be less than the totalpurchase (totalpurchase which i had setted in the session),but my jsp page is unable to rechognise the updated value of the totalpurchase, yes, if i reload the page, it rechognises the new updated value of the totalpurchase? but i want it to rechognise the updated total purchase value, without reloading he jsp page..
I have a managed bean for a form. I map the fields filled in the form with managed bean properties. when I submit the form and click new form , values from the previous form submitted gets displayed in the input fields. I used the scope of the from bean to session. what should be its scope so that values should be destroyed after I submit the form .For every new form ,new bean has to be initialized. On submit I navigate to another bean with session scope.
I am working on eclipse kepler, JSF 2.2 with PrimeFaces 4.0 / Mojarra 2.2 library.
actually there are 2 Problems:
I still get this server message no matter what I do.
(( javax.el.PropertyNotFoundException: /Order.xhtml @28,76 value="#{kk.refugee.id}": Target Unreachable, 'refugee' returned null))
and if I delete the input text puls the hidden, the message keeps pop up for 'material' selectOneMenu. -
I have no chance to examin : ((is this javascript code correct, to copy the value of one component to the other.)) these are my xhtml file and java calsses.
**kk.java** ----------- package khldqr.beans; import javax.faces.bean.ManagedBean; import javax.faces.bean.SessionScoped; @SessionScoped @ManagedBean public class kk {
I have a JSF bean which is request scope and corresponding JSF UI page. when user tries to open this page, we are getting exception 'Cannot instantiate user.java class <default constructor>'. This does not come always. It comes very rarely. JSF version is 1.2
I have a bean that represents data been collected from a form on a jsp page. Currently I would like to validate my fields and write some test cases for them. As you can see from my test case example I test a string in the hope that it fails because it contains only one letter. My problem is my unit test is passing. The reason this is from what I can tell is that at runtime it fails when I try to persist my object using my entity manager. During my unit test I just I don’t call my entity manager I just try and set the field.
What I thought would happen was that when I use my bean fields set method the annotations would be checked and fail at that point. Hence why I expected my unit test in this case to fail.
What I would like to know is
1.Are annotations specifically designed to validate when I persist my object and am I using them incorrectly at this point?
2.Is this the best method to use to validate fields, is there a better way, should I write my own code to validate for me when I set my value?
a. Should I throw an exception from the set method of each bean field?
Unit Test:
@Test public void testName(){ Human h=new Human(); try { h.setFname("a"); } catch (Exception e) { // TODO Auto-generated catch block fail("failed"); e.printStackTrace();
1. When we have a view and this uses two or three managed beans and not only one, is this ok? is a good design?
2 If we have two views and both of them only share one functionality (they need to display datatable with clients) , for the second view and for the shared functionality, should I in the managed bean for the second view create the same method that gets the clients or reuse the method in the managed bean created for the first view?
I got the correct output here. But now I want to generalize my method into a utility class so that I can reuse the same method for setting response data directly to respective beans as given below:-
My question is how will I pass the bean object in my utility class?
public static Object getResponseData(String response,[b]String bean[/b]) throws Exception { ObjectMapper mapper = new ObjectMapper(); mapper.configure(DeserializationConfig.Feature.FAIL_ON_UNKNOWN_PROPERTIES, false); JsonNode root = mapper.readTree(response);
i get this error when trying to Persist a customer Entity in my web application using netbeans with the default glassfish server persistence provider eclipselink(JPA2.0)
error is
SEVERE: javax.validation.ConstraintViolationException: Bean Validation constraint(s) violated while executing Automatic Bean Validation on callback event:'prePersist'. Please refer to embedded ConstraintViolations for details.
the table that i want to write to has the following colums id ==> primarykey auto increment not null int name == varchar(45) not null phone ==> varchar(19) nationalIdNo ==>varchar(19) balance ==> bigdecimal(6,2) not null default(0.00)
in my addNewCustomer i only need to set name, phone and nationalIdNo only this is my code
/* * To change this template, choose Tools | Templates * and open the template in the editor. */ package session;
