I have faced a problem which may be common in this forum but found no good solution.
Why this problem occurs and how to solve.
My program details are as follows
#Named("login")
#SessionScoped
public class Login implements Serializable {
private String userId;
private String password;
#Inject
private UserBeanLocal userBean;
public Login() {
}
public String getUserId() {
return userId;
}
public void setUserId(String userId) {
this.userId = userId;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
public String isValid(){
if(userBean.getUser(userId).getPassword().equals(getPassword())) {
return "home?faces-redirect=true";
}
return "index?faces-redirect=true";
}
and the index.xhtml
<h:form>
<h:outputText class="title" value="Login"/><br/>
<h:inputText id="userId"
value="#{login.userId}"
requiredMessage="User Id is required!" /><br />
<h:inputText id="password"
value="#{login.password}"
requiredMessage="Password is required!"/>
<h:commandButton id="submit"
value="Submit"
action="#{login.isValid()}"/>
</h:form>
and the web.xml and beans.xml file is already there..
Did the CDI container boot properly? Please review your logs or try to inject an interface with no implementation and make sure that an exception is thrown.
Further if you have nothing defined in beans.xml then please remove everything in the file so that it's completely empty.
Remove the ("login") part of your #Named definition, it is superfluous to override with exact same value it would default to.
Make sure #SessionScoped is imported using the correct package. What you want is javax.enterprise.
Further answer the following questions:
1) What is your container?
2) Has CDI worked previously or is this your first try?
3) Describe the exact location of your beans.xml file.
Pasting your boot log from your servlet container would be helpful too (Tomcat, jboss whatever)
Related
I would like to pass an value to a managed bean under the hood. So I have this managed bean:
#ManagedBean(name = "mbWorkOrderController")
#SessionScoped
public class WorkOrderController {
// more attributes...
private WorkOrder workOrderCurrent;
// more code here...
public WorkOrder getWorkOrderCurrent() {
return workOrderCurrent;
}
public void setWorkOrderCurrent(WorkOrder workOrderCurrent) {
this.workOrderCurrent = workOrderCurrent;
}
}
It holds a parameter workOrderCurrent of the custom type WorkOrder. The class WorkOrder has an attribute applicant of type String.
At the moment I am using a placeholder inside my inputtext to show the user, what he needs to type inside an inputText.
<p:inputText id="applicant"
value="#{mbWorkOrderController.workOrderCurrent.applicant}"
required="true" maxlength="6"
placeholder="#{mbUserController.userLoggedIn.username}" />
What I want to do, is to automatically pass the value of mbUserController.userLoggedIn.username to mbWorkOrderController.workOrderCurrent.applicant and remove the inputText for applicant completely from my form.
I tried to use c:set:
<c:set value="#{mbUserController.userLoggedIn.username}" target="#{mbWorkOrderController}" property="workOrderCurrent.applicant" />
But unfortunatelly I get a javax.servlet.ServletException with the message:
The class 'WorkOrderController' does not have the property 'workOrderCurrent.applicant'.
Does anybody have an advice?
The class 'WorkOrderController' does not have the property 'workOrderCurrent.applicant'.
Your <c:set> syntax is incorrect.
<c:set value="#{mbUserController.userLoggedIn.username}"
target="#{mbWorkOrderController}"
property="workOrderCurrent.applicant" />
You seem to be thinking that the part..
value="#{mbWorkOrderController.workOrderCurrent.applicant}"
..works under the covers as below:
WorkOrderCurrent workOrderCurrent = mbWorkOrderController.getWorkOrderCurrent();
workOrderCurrent.setApplicant(applicant);
mbWorkOrderController.setWorkOrderCurrent(workOrderCurrent);
This isn't true. It works under the covers as below:
mbWorkOrderController.getWorkOrderCurrent().setApplicant(applicant);
The correct <c:set> syntax is therefore as below:
<c:set value="#{mbUserController.userLoggedIn.username}"
target="#{mbWorkOrderController.workOrderCurrent}"
property="applicant" />
That said, all of this isn't the correct solution to the concrete problem you actually tried to solve. You should perform model prepopulating in the model itself. This can be achieved by using #ManagedProperty to reference another bean property and by using #PostConstruct to perform initialization based on it.
#ManagedBean(name = "mbWorkOrderController")
#SessionScoped
public class WorkOrderController {
#ManagedProperty("#{mbUserController.userLoggedIn}")
private User userLoggedIn;
#PostConstruct
public void init() {
workOrderCurrent.setApplicant(userLoggedIn.getUsername());
}
// ...
}
Perhaps you could explain the context a bit more, but here's another solution. If you're navigating from another page, you can pass some identifier of work WorkOrder in the URL, like this http://host:port/context/page.xhtml?workOrderId=1.
Then, you can set the identifier in the managed bean like this:
<h:html>
<f:viewParam name="workOrderId" value="#{mbWorkOrderController.id}"/>
</h:html>
You'll have to add a new property to your bean:
public class WorkOrderController {
private long id;
public long getId() { return id; }
public void setId(long id) { this.id = id; }
// ...
}
And then, after the property has been set by JSF, you can find the work order in a lifecycle event:
<h:html>
<f:viewParam name="workOrderId" value="#{mbWorkOrderController.id}"/>
<f:event type="preRenderView" listener="#{mbWorkOrderController.findWorkOrder()}"/>
</h:html>
public class WorkOrderController {
private long id;
public long getId() { return id; }
public void setId(long id) { this.id = id; }
public void findWorkOrder() {
this.workOrderCurrent = null /* some way of finding the work order */
}
// ...
}
This strategy has the advantage of letting you have bookmarkable URLs.
Edit: The comment section solved my problem! The problem was that I was using incorrect imports for the Scopes.
I have a simple JSF application (login, pull data from database, allow user to edit data). It works well, I want to update the code to use CDI (Weld), but I am having trouble.
I am following / looking at: http://docs.jboss.org/weld/reference/latest/en-US/html/example.html
Original stuff without Weld:
login.xhtml
<h:form id="inputForm">
<h:panelGrid columns="2" cellpadding="5" cellspacing="1">
<h:outputText id="nameDesc" value="Name"></h:outputText>
<h:inputText id="nameInput" value="#{login.loginName}" binding="#{name}"></h:inputText>
<h:outputText id="passwordDesc" value="Password"></h:outputText>
<h:inputSecret id="passwordInput" value="#{login.password}" binding="#{password}"></h:inputSecret>
</h:panelGrid>
<h:commandButton value="Login" action="#{login.login(name.value, password.value)}"/>
</h:form>
LoginBean.java:
#ManagedBean(name="login")
#SessionScoped
public class LoginBean implements Serializable {
private static final long serialVersionUID = 1L;
#ManagedProperty(value="#{db}")
private DatabaseBean db;
private String password;
private String loginName;
// other stuff and functions
public String getLoginName () {
return loginName;
}
public void setLoginName (String name) {
this.loginName = name;
}
public String getPassword () {
return password;
}
public void setPassword (final String password) {
this.password = password;
}
public void setDb(DatabaseBean db) {
this.db = db;
}
DatabaseBean.java:
#ManagedBean(name="db", eager=true)
#ApplicationScoped
public class DatabaseBean implements Serializable {
#PostConstruct
public void init() {
//... connect to database etc
}
}
---------What I tried to get it running with Weld (only changes from above to make it a bit shorter): --------
LoginBean.java, changed to #Named from #ManagedBean, added #Inject for DatabaseBean
#Named("login")
#SessionScoped
public class LoginBean implements Serializable {
// stuff
private #Inject DatabaseBean db;
}
DatabaseBean.java, changed to #Named from #ManagedBean:
#Named("db")
#ApplicationScoped
public class DatabaseBean implements Serializable {
}
LoginBean has a function:
public String login(String name, String password) {
System.out.println("login called"+name);
// other stuff
}
With my second implementation (the one where I try to use Weld), the print is called once: "login called", and the username is empty (I checked this with name.IsEmpty()).
I have also tried injecting it by constructor:
loginBean.java
#Inject
public LoginBean(DatabaseBean db) {
System.out.println("constructor");
this.db = db;
}
When I do this the I get lots of "constructor" prints, so it is called several times, but I don't see why - I guess this is the problem though, only one instance of LoginBean gets the input (username and password) and then lots of new ones are created for some reason. Why is that?
I use Eclipse and Tomcat8 to run it.
Thank you for reading!
managed bean constructor called multiple times
CDI may call constructor more often than expected while generating/creating enhanced subclasses/proxies. See also Field.get(obj) returns all nulls on injected CDI managed beans, while manually invoking getters return correct values. Just do not log constructor invocation, it would only confuse yourself. #PostConstruct is the only interesting method to hook on.
the print is called once: "login called", and the username is empty (I checked this with name.IsEmpty()).
As to the concrete problem of form input values being null when the action method is invoked, and thus the #SessionScoped CDI managed bean seemingly being recreated on every access, this matches the behavior of a #Dependent scoped bean. This is the default scope when no valid CDI managed bean scope can be found. See also What is the default Managed Bean Scope in a JSF 2 application?
This in turn suggests you imported #SessionScoped from the wrong package. Make sure it's from the javax.enterprise.context package and not from e.g. javax.faces.bean. JSF managed bean scopes are not recognizable as valid CDI managed bean scopes.
import javax.inject.Named;
import javax.enterprise.context.SessionScoped;
#Named("login")
#SessionScoped
public class LoginBean implements Serializable {
// ...
}
I have started learning JSF, but sadly most tutorials out there present only a log in or a register section.
Can you point me to some more in depth examples? One thing I'm interested in is a page presenting a list of products. I'm on page home and I press on page products so that I can see the latest products added. And every time I visit the page, the product list will be created from the latest entries in the database. How can I handle this?
One way to solve this would be to create a session scoped managed bean in which I would place different entities updated through other managed beans. I found this kind of approach in some tutorials, but it seems quite difficult and clumsy.
Which would be the best approach to solve a thing like this? What is the correct usage of session scope in two-page master-detail user interface?
What is the correct usage of session scope
Use it for session scoped data only, nothing else. For example, the logged-in user, its settings, the chosen language, etcetera.
See also:
How to choose the right bean scope?
And every time I visit the page, the product list will be created from the latest entries in the database. How can I handle this?
Typically you use the request or view scope for it. Loading of the list should happen in a #PostConstruct method. If the page doesn't contain any <h:form>, then the request scope is fine. A view scoped bean would behave like a request scoped when there's no <h:form> anyway.
All "view product" and "edit product" links/buttons which just retrieve information (i.e. idempotent) whould be just plain GET <h:link> / <h:button> wherein you pass the entity identifier as a request parameter by <f:param>.
All "delete product" and "save product" links/buttons which will manipulate information (i.e. non-idempotent) should perform POST by <h:commandLink>/<h:commandButton> (you don't want them to be bookmarkable/searchbot-indexable!). This in turn requires a <h:form>. In order to preserve the data for validations and ajax requests (so that you don't need to reload/preinitialize the entity on every request), the bean should preferably be view scoped.
Note that you should basically have a separate bean for each view and also note that those beans doesn't necessarily need to reference each other.
So, given this "product" entity:
#Entity
public class Product {
#Id
private Long id;
private String name;
private String description;
// ...
}
And this "product service" EJB:
#Stateless
public class ProductService {
#PersistenceContext
private EntityManager em;
public Product find(Long id) {
return em.find(Product.class, id);
}
public List<Product> list() {
return em.createQuery("SELECT p FROM Product p", Product.class).getResultList();
}
public void create(Product product) {
em.persist(product);
}
public void update(Product product) {
em.merge(product);
}
public void delete(Product product) {
em.remove(em.contains(product) ? product : em.merge(product));
}
// ...
}
You can have this "view products" on /products.xhtml:
<h:dataTable value="#{viewProducts.products}" var="product">
<h:column>#{product.id}</h:column>
<h:column>#{product.name}</h:column>
<h:column>#{product.description}</h:column>
<h:column>
<h:link value="Edit" outcome="/products/edit">
<f:param name="id" value="#{product.id}" />
</h:link>
</h:column>
</h:dataTable>
#Named
#RequestScoped
public class ViewProducts {
private List<Product> products; // +getter
#EJB
private ProductService productService;
#PostConstruct
public void init() {
products = productService.list();
}
// ...
}
And you can have this "edit product" on /products/edit.xhtml:
<f:metadata>
<f:viewParam name="id" value="#{editProduct.product}"
converter="#{productConverter}" converterMessage="Unknown product, please use a link from within the system."
required="true" requiredMessage="Bad request, please use a link from within the system."
/>
</f:metadata>
<h:messages />
<h:form rendered="#{not empty editProduct.product}>
<h:inputText value="#{editProduct.product.name}" />
<h:inputTextarea value="#{editProduct.product.description}" />
...
<h:commandButton value="save" action="#{editProduct.save}" />
</h:form>
#Named
#ViewScoped
public class EditProduct {
private Product product; // +getter +setter
#EJB
private ProductService productService;
public String save() {
productService.update(product);
return "/products?faces-redirect=true";
}
// ...
}
And this converter for <f:viewParam> of "edit product":
#Named
#RequestScoped
public class ProductConverter implements Converter {
#EJB
private ProductService productService;
#Override
public Object getAsObject(FacesContext context, UIComponent component, String value) {
if (value == null || value.isEmpty()) {
return null;
}
try {
Long id = Long.valueOf(value);
return productService.find(id);
} catch (NumberFormatException e) {
throw new ConverterException("The value is not a valid Product ID: " + value, e);
}
}
#Override
public String getAsString(FacesContext context, UIComponent component, Object value) {
if (value == null) {
return "";
}
if (value instanceof Product) {
Long id = ((Product) value).getId();
return (id != null) ? String.valueOf(id) : null;
} else {
throw new ConverterException("The value is not a valid Product instance: " + value);
}
}
}
You can even use a generic converter, this is explained in Implement converters for entities with Java Generics.
See also:
How to navigate in JSF? How to make URL reflect current page (and not previous one)
JSF Controller, Service and DAO
JSF Service Layer
How to inject #EJB, #PersistenceContext, #Inject, #Autowired, etc in #FacesConverter?
Communication in JSF 2.0 - Contains several examples/hints
As a small improvement to what BalusC recommended, sometimes you can remove the required / requiredMessage part from the <f:viewParam> of your "details" screen and instead use the conditional rendering of the editing form (as BalusC did) with a reverse condition for recommending a specific link for the "list/master" screen or, even use a viewAction that would test the param and force a redirect to that list.
I am using a session scoped managed bean for handling login in a Java EE application. After I authenticate the user, the user object is saved in this session bean. However, after I refresh the page, the session bean values are gone.
I was debugging the code and it results that the constructor of the session scoped managed bean is called again on page refresh, therefore initializing the user object with a new user. I guess this is not a normal behavior since it should be preserved on the session shouldn't it?
I am posting some parts of the login managed bean including the parameters and the login method. Basically the enteredEmail and enteredPassword stand for the entered data on the login form. If the authentication succeeds, the loggedIn boolean is turned to true and the logged in user object is stored in the checkedUser variable.
import javax.faces.bean.ManagedBean;
import javax.faces.bean.SessionScoped;
#ManagedBean
#SessionScoped
public class LoginController implements Serializable {
#EJB
private LoginSessionBean loginSessionBean;
#EJB
private LecturerFacade lecturerFacade;
private Lecturer checkedUser;
private String enteredEmail;
private String enteredPassword;
private boolean loggedIn;
/** Creates a new instance of loginController */
public LoginController() {
loggedIn = false;
checkedUser = new Lecturer();
}
public String login(){
RequestContext context = RequestContext.getCurrentInstance();
FacesMessage msg = null;
this.setCheckedUser(lecturerFacade.findLecturerByEmail(enteredEmail));
if(loginSessionBean.checkPassword(checkedUser, enteredPassword))
{
loggedIn = true;
msg = new FacesMessage(FacesMessage.SEVERITY_INFO, "Welcome", checkedUser.getFirstName()+ " " + checkedUser.getLastName());
FacesContext.getCurrentInstance().addMessage(null, msg);
context.addCallbackParam("loggedIn", loggedIn);
}
return "Index";
I am also posting the two EJBs that the above managed bean uses. The lecturerFacade retrieves the user object with the entered email, while the loginSessionBean checks the password.
#Stateless
public class LecturerFacade extends AbstractFacade<Lecturer> {
#PersistenceContext(unitName = "EffectinetWebPU")
private EntityManager em;
Logger logger = Logger.getLogger("MyLog");
FileHandler fh;
protected EntityManager getEntityManager() {
return em;
}
public LecturerFacade() {
super(Lecturer.class);
}
public Lecturer findLecturerByEmail(String email) {
try {
return (Lecturer) this.getEntityManager().createQuery("SELECT l FROM Lecturer l WHERE l.email = :email").setParameter("email", email).getSingleResult();
} catch (NoResultException e) {
System.err.println("Caught NOResultException: "+ e.getMessage());
return null;
} catch (NonUniqueResultException e) {
System.err.println("Caught NonUniqueResultException: "+ e.getMessage());
return null;
} catch (IllegalStateException e) {
System.err.println("Caught IllegalStateException: "+ e.getMessage());
return null;
}
}
_
#Stateless
public class LoginSessionBean {
// Add business logic below. (Right-click in editor and choose
// "Insert Code > Add Business Method")
#PersistenceContext(unitName = "EffectinetWebPU")
private EntityManager em;
protected EntityManager getEntityManager() {
return em;
}
public void setEntityManager(EntityManager em) {
this.em = em;
}
public boolean checkPassword(Lecturer user, final String enteredPassword) {
if (user.getPassword().equals(enteredPassword)) {
return true;
} else {
return false;
}
}
}
Please if someone has any suggestion of what is going wrong, please tell me
Im using glassfish 3.1 as application server and Primefaces as JSF library. Also, I have checked and the imported the sessionScoped annotation from the right package and not from javax.enterprise...
Your problem is thus here:
<p:menuitem value="Logout" ... onclick="#{loginController.logout()}"/>
The onclick attribute should represent a JavaScript handler function which is to be executed in the webbrowser when the enduser clicks the element. Something like
onclick="alert('You have clicked this element!')"
The onclick attribute also accepts a ValueExpression, so you can even let JSF/EL autogenerate its value accordingly:
onclick="#{bean.onclickFunction}"
with
public String getOnclickFunction() {
return "alert('You have clicked this element!')";
}
All the EL is thus evaluated when the page is rendered. In your particular case, the logout() method is called everytime the EL is evaluated and thus you're invalidating the session everytime the page is rendered!
You need to bind it to an attribute which takes a MethodExpression like <h:commandLink action>, <h:commandButton action> and in this particular case <p:menuitem action>.
<p:menuitem value="Logout" ... action="#{loginController.logout()}"/>
This can be understood by understanding basic HTML and JavaScript concepts and keeping in mind that JSF ultimately produces HTML/CSS/JS. Open the JSF page in webbrowser, rightclick and View Source to realize it.
Well I managed to solve it today. This was the problem, although I cannot explain why:
I was using Primefaces 3.2 as JSF library so this was the main menu of the index page.
<h:form>
<p:menubar >
<p:menuitem id="registerLink" value="Register" rendered="#{!loginController.loggedIn}" onclick="registerDialog.show()" />
<p:menuitem id="loginLink" value="Login" rendered="#{!loginController.loggedIn}" onclick="loginDialog.show()" />
<p:submenu label="Units" rendered="true">
<p:menuitem id="addNew" value="Add New" onclick="createUnitDialog.show()" />
<p:menuitem id="myUnits" value="My Units" onclick="" />
</p:submenu>
<p:menuitem id="results" value="Results/Statistics" rendered="#{loginController.loggedIn}" onclick=""/>
<p:menuitem id="profile" value="My Profile" rendered="#{loginController.loggedIn}" onclick=""/>
<p:menuitem id="logout" value="Logout" rendered="#{loginController.loggedIn}" onclick="#{loginController.logout()}"/>
</p:menubar>
</h:form>
After setting breakpoints to the whole code I discovered that the logout() method, which is supposed to destroy the managed bean, was called on every page refresh. I don't know why this happened as it should be called when the logout menuitem was clicked.
However, after changing the onclick="#{loginController.logout()} with action="#{loginController.logout()} the problem was solved.
I checked the documentation of Primefaces but nowhere this behavior was explained
When login page is loaded the input text box is displaying #{ad.userid}. When I erased it and entered id and pwd and clicked submit button the login method is called but userid property is giving null value in bean. How can this happen and how can I solve it?
Here is the login.jsp:
<%# page contentType="text/html"%>
<%# taglib uri="http://java.sun.com/jsf/core" prefix="f" %>
<%# taglib uri="http://java.sun.com/jsf/html" prefix="h" %>
<f:view>
<html>
<h:form>
<h:outputText value="Login"/>
<h:inputText value="#{ad.userid}" id="log" required="true"/>
<h:outputText value="Password" />
<h:inputSecret id="pw" value="#{ad.password}" required="true"/>
<h:commandButton value="submit" action="#{ad.login}"/>
</h:form>
</body>
</html>
</f:view>
Here is the bean's action method. The login worked successfully earlier. All db connections are set in constructor.
public String login() {
ResultSet rs;
try {
System.out.println(userid); // this is giving null
String s = "select id from slogin where id='" + userid + "'";
System.out.println(s);
rs = st.executeQuery(s);
if (rs.next()) {
String loginid = rs.getString(1);
if (userid.equals(loginid)) {
id = loginid;
return "studhome";
}
} else {
System.out.println("error");
}
} catch(Exception e) {
}
}
Getter and setter methods:
public void setpassword(String pass) {
this.password = pass;
}
public String getpassword() {
return password;
}
public void setuserid(String uid) {
this.userid = uid;
}
public String getuserid() {
return userid;
}
Please, take your time to edit your question, format it properly using the formatting code tools that StackOverflow provides. The braces will appear if you use the button with the symbol "0101010101".
The answer:
Change:
public void setuserid(String uid)
to
public void setUserid(String uid)
and also:
public void setpassword(String pass)
to
public void setPassword(String pass)
Have a look at Java Naming Conventions, JSF relies on them to access the properties of a managed bean.
Btw, try to set your backing bean to Session scope to see if it works, to discard other problems
I am not sure if this is helpful -
1) add debug(sysouts) statements in the getters and setters and use the naming conventions as said by pakore (better you can ask eclipse to generate getters and setters).
2) try to write a Phaselistener to see if all the apply request and update model phases of jsf life cycle happens.