I have two scenario
I have two actions which have logic in bean like
My buttons
<h:commandButton value="Submit" action="#{bean.test}" />
<h:commandButton value="Submit" action="#{bean.testOne}" />
This are the two commnadButtons and there logic in bean
public void test() {
log.info("I m in test");
}
public void testOne() {
log.info("I m in testOne");
try {
FacesContext.getCurrentInstance()
.addMessage("", new FacesMessage("Record Saved successfully."));
FacesContext
.getCurrentInstance()
.getExternalContext()
.redirect(
FacesContext.getCurrentInstance()
.getExternalContext().getRequestContextPath()
+ "/cycle/page");
} catch (IOException e) {
log.error(e.getMessage());
}
}
When I am going to click on 1st button (test action) that time jsf life cycle goes to every phase like restore view Apply request valuesProcess validationupdate modelsinvoke applicationrender response
But when I click on testOne button that time jsf life cycle skip render response after invoke application like restore view Apply request valuesProcess validationupdate modelsinvoke applicationrestore viewrender response
In simple language When I am navigate the page through facesContext that time jsf skips that phase.
But why this happens? I am not getting the problem.
According to the JSF docs, that's what the INVOKE_APPLICATION phase does:
During this phase, the JavaServer Faces implementation handles any application-level events, such as submitting a form or linking to another page.
At this point, if the application needs to redirect to a different web application resource or generate a response that does not contain any JavaServer Faces components, it can call the FacesContext.responseComplete method.
If the view being processed was reconstructed from state information from a previous request and if a component has fired an event, these events are broadcast to interested listeners.
Finally, the JavaServer Faces implementation transfers control to the Render Response phase.
What you're doing is calling FacesContext#getCurrentInstance#getExternalContext#redirect in this phase, which performs your redirection. This method triggers FacesContext#getCurrentInstance#responseComplete, which ends the JSF lifecycle. The redirection is performed to a JSF view, so a new cycle starts after that.
Apart from that and unrelated to the concrete issue, do not perform redirections like that if you want to redirect to an internal JSF view. Just return the navigation case + ?faces-redirect=true in your action method (i.e. /cycle/page?faces-redirect=true). Use the external context only if you want to access external urls.
See also:
JSF INVOKE_APPLICATION
Redirection in JSF
Related
I am new to JSF and UI.
I want that when I click on submenu my business logic should execute and after that my page get renders. I tried below snippet but its not working, page is getting rendered but actionListener is not getting executed. when I remove the url part, the actionListener is working but now I am stuck like how to render the page.
<ace:menuItem id="RedactionCapture" value="Redaction"
actionListener="#{redactionController.getRedactionList}"
url="#{firmUtility.legalHoldCreationOrRemovalUrl}"
style="width:220px" styleClass="dropdownmenu"
target="imagepgframe">
</ace:menuItem>
That is expected behavior. An actionListener is a listener for an action and not for a URL. You could create an action which does a redirect to the URL in combination with the listener or do all the work in the action. Please note that this not only the case in IceFaces, but also in PrimeFaces.
For example (with a listener), XHTML:
<ace:menuItem action="#{yourBean.redirect(firmUtility.legalHoldCreationOrRemovalUrl)}"
actionListener="#{redactionController.getRedactionList}"
... />
Bean:
public void redirect(String url) throws IOException {
ExternalContext externalContext = FacesContext.getCurrentInstance().getExternalContext();
externalContext.redirect(url);
}
See also:
Redirect to external URL in JSF
Differences between action and actionListener
In a JSF managed bean constructor, I load a entity from database usint a request parameter. Some times, the entity is not in database and I want to show other JSF (.xhtml) page with 404 message.
This is a sample of managed bean:
#ManagedBean(name = "someBean")
#RequestScoped
public class SomeBean implements Serializable {
private static final long serialVersionUID = 1L;
private SomeData someData;
public SomeBean() throws IOException {
someData = ... loads from database using JPA features
if(someData == null){
HttpServletResponse response = (HttpServletResponse) FacesContext
.getCurrentInstance().getExternalContext().getResponse();
response.sendError(404);
}
}
public SomeData getSomeData(){
return someData;
}
}
I configured the web.xml file something like that:
<error-page>
<error-code>404</error-code>
<location>/404.xhtml</location>
</error-page>
I have a JSF page to handle the entity loaded by managed bean. When the entity exists, I will use it in the page. Like that:
<h1>#{someBean.someEntity.name}</h1>
<h2>#{someBean.someEntity.description}</h2>
<ui:repeat value="#{someBean.someEntity.books}" var="book">
// ..........
</ui:repeat>
The page above works when the managed loads the data successfully.
The Problem
When the entity not exists and I send a 404 ERROR CODE, the JSF still process methods defined in the expression language of the first page.
This behavior makes the managed bean throws a NullPointerException, and a HTTP 500 ERRO CODE.
My 404 error page is not called. I do not know why.
I try send the 404 error even when the entity is found in database and the 404 error page works.
Enyone can explain this JSF behavior to this happiness? Or offer some kind to show the 404 error page without URL change ?
You're basically trying to perform front controller logic while rendering the view. You should do it before rendering the view. Because, once you start rendering the view, it's already too late to change the view to a different destination, e.g. an error page as in your case. You namely cannot take the already sent response back from the client.
In JSF 2.2 you can use <f:viewAction> for this.
<f:metadata>
<f:viewAction action="#{bean.init}" />
</f:metadata>
public void init() {
// ...
if (someCondition) {
context.getExternalContext().responseSendError(404, "some message");
context.responseComplete();
}
}
(note that whenever you need to import javax.servlet.* classes into your JSF backing bean, you should absolutely stop and look if the functionality isn't already available in ExternalContext or otherwise think twice if you're doing things the right way, e.g. perhaps you needed a servlet filter; also note that you need to explicitly tell JSF that you've completed the response, otherwise it will still attempt to render the view)
In JSF 2.0/2.1 you can use <f:event type="preRenderView"> for this. See also among others What can <f:metadata>, <f:viewParam> and <f:viewAction> be used for?
In case you're actually trying to validate a HTTP request parameter and you also happen to use OmniFaces, you may consider using <f:viewParam> with a true JSF validator and control the sendError with OmniFaces <o:viewParamValidationFailed>.
I know this type of question has been asked million times here, but I couldn't find a solution for my problem in relevant posts.
JSF 1.2
I have a request-scoped bean with a method used as valueChangeListener:
class DoStuff{
...
public void step1ChkStuffIncluded_CheckedChanged(ValueChangeEvent event){
StuffDocument cd = (StuffDocument)getInfo("StuffDocument");
if(cd == null){
Logger.Error("DoStuff", "step1ChkStuffIncluded_CheckedChanged", "No stuff document (null)");
return;
}
if (step1ChkStuffIncludedChecked){
cd.handleChecked();
}
else{
cd.handleUnchecked();
}
}
...
}
by a selectBooleanCheckbox component as follows (.jspx):
...
</h:panelGroup>
<h:panelGroup rendered="#{DoStuff.pnlStep1}">
<p>
<label for="step1ChkStuffIncluded">#{DoStuff.step1ChkStuffIncludedText}</label>
<h:selectBooleanCheckbox
id="step1ChkStuffIncluded"
onchange="submit();"
value="#{DoStuff.step1ChkStuffIncludedChecked}"
valueChangeListener="#{DoStuff.step1ChkStuffIncluded_CheckedChanged}">
</h:selectBooleanCheckbox></p>
</h:panelGroup>
<div id="someDiv">
...
where
xmlns:h="http://java.sun.com/jsf/html"
Whenever the bean's scope is session, both setter and the listener for the checkbox are executed, but not in request scope. Unfortunately I can't find any clues other than that.
Any advise is greatly appreciated. Requests for further clarifications are welcome.
You've there a rendered="#{DoStuff.pnlStep1}" on a parent component. During processing of the form submit, JSF will as part of attack safeguard determine if the input component (and all of its parents) is rendered according to the server side conditions. If it's not rendered, then it will simply be skipped altogether during the processing.
That it works in a session scoped bean but fails in a request scoped bean indicates that the value behind rendered="#{DoStuff.pnlStep1}" is determined based on some request based variable/condition which was present during the request of displaying the form, but is absent during the request of processing the form submit.
To fix this, you need to make sure that you preserve exactly the same variable/condition for the value behind rendered="#{DoStuff.pnlStep1}" during the request of processing the form submit. There are several ways to achieve this, depending on the nature of the condition and how you're submitting the form. One of the ways is to pass the request based variable/condition back as a request parameter by <f:param> or <h:inputHidden>.
The canonical JSF 2.0 fix would be to put the bean in the view scope which is not available in JSF 1.2, but can be simulated using Tomahawk's <t:saveState> component.
See also:
JSF 1.2: How to keep request scoped managed bean alive across postbacks on same view?
How to call an action method of a UICommand Component which was rendered conditionally?
In a JSF managed bean constructor, I load a entity from database usint a request parameter. Some times, the entity is not in database and I want to show other JSF (.xhtml) page with 404 message.
This is a sample of managed bean:
#ManagedBean(name = "someBean")
#RequestScoped
public class SomeBean implements Serializable {
private static final long serialVersionUID = 1L;
private SomeData someData;
public SomeBean() throws IOException {
someData = ... loads from database using JPA features
if(someData == null){
HttpServletResponse response = (HttpServletResponse) FacesContext
.getCurrentInstance().getExternalContext().getResponse();
response.sendError(404);
}
}
public SomeData getSomeData(){
return someData;
}
}
I configured the web.xml file something like that:
<error-page>
<error-code>404</error-code>
<location>/404.xhtml</location>
</error-page>
I have a JSF page to handle the entity loaded by managed bean. When the entity exists, I will use it in the page. Like that:
<h1>#{someBean.someEntity.name}</h1>
<h2>#{someBean.someEntity.description}</h2>
<ui:repeat value="#{someBean.someEntity.books}" var="book">
// ..........
</ui:repeat>
The page above works when the managed loads the data successfully.
The Problem
When the entity not exists and I send a 404 ERROR CODE, the JSF still process methods defined in the expression language of the first page.
This behavior makes the managed bean throws a NullPointerException, and a HTTP 500 ERRO CODE.
My 404 error page is not called. I do not know why.
I try send the 404 error even when the entity is found in database and the 404 error page works.
Enyone can explain this JSF behavior to this happiness? Or offer some kind to show the 404 error page without URL change ?
You're basically trying to perform front controller logic while rendering the view. You should do it before rendering the view. Because, once you start rendering the view, it's already too late to change the view to a different destination, e.g. an error page as in your case. You namely cannot take the already sent response back from the client.
In JSF 2.2 you can use <f:viewAction> for this.
<f:metadata>
<f:viewAction action="#{bean.init}" />
</f:metadata>
public void init() {
// ...
if (someCondition) {
context.getExternalContext().responseSendError(404, "some message");
context.responseComplete();
}
}
(note that whenever you need to import javax.servlet.* classes into your JSF backing bean, you should absolutely stop and look if the functionality isn't already available in ExternalContext or otherwise think twice if you're doing things the right way, e.g. perhaps you needed a servlet filter; also note that you need to explicitly tell JSF that you've completed the response, otherwise it will still attempt to render the view)
In JSF 2.0/2.1 you can use <f:event type="preRenderView"> for this. See also among others What can <f:metadata>, <f:viewParam> and <f:viewAction> be used for?
In case you're actually trying to validate a HTTP request parameter and you also happen to use OmniFaces, you may consider using <f:viewParam> with a true JSF validator and control the sendError with OmniFaces <o:viewParamValidationFailed>.
In a previous question BalusC gave me good advice on how a button, in place of a commandButton is useful for non ajax navigation. In particular it updates the destination address in the http: position which is useful for the user to bookmark a page.
I tried to use this information to my advantage until I came upon a problem. In a button I tried to use outcome="#{backing.something}" to find out that it gives me a null result. This looks like a timing problem in that action="#{}" is evaluated only when the button is pressed whereas outcome apparently wants a fixed string which gets checked when the page is loaded.
So I went back to commandButton with ajax="false". This has a problem that my navigation address is the page I came from, not the one I am navigating to. This is the wrong bookmark for the user.
I appreciate all the help I have received in stackoverflow on my learning exercise.
Ilan
The <h/p:button outcome> is not intented to invoke a bean action method, but to contain the outcome string directly. Any EL in there is evaluated immediately as a value expression. So the method behind it would immediately be invoked when you just open the page containing the <h/p:button>.
There are in your particular case basically two ways to invoke a bean action method on navigation. If you need to invoke it before the navigation takes place and the action isn't intented to be re-invoked everytime when the enduser reopens/reloads the GET request, then make it a POST-Redirect-GET request. It's a matter of adding faces-redirect=true to the outcome value in query string syntax.
E.g.
<p:commandButton action="#{bean.submit}" ... />
with
public String submit() {
// ...
return "nextpage?faces-redirect=true";
}
This way the browser will be redirected to the target page after POST, hence the enduser will see the target URL being reflected in the address bar.
Or if you need to invoke the action everytime when the enduser reopens/reloads the GET request, do the job in the (post)constructor or preRenderView listener method of the request/view scoped backing bean instead.
E.g.
<p:button outcome="nextpage" ... />
with
#ManagedBean
#RequestScoped
public class NextpageBacking {
public NextpageBacking() {
// In constructor.
}
#PostConstruct
public void onPostConstruct() {
// Or in postconstructor (will be invoked after construction AND injection).
}
public void onPreRenderView() {
// Or before rendering the view (will be invoked after all view params are set).
}
// ...
}
The pre render view listener method needs to be definied as follows in the nextpage
<f:event type="preRenderView" listener="#{nextpageBacking.onPreRenderView}" />
See also:
What can <f:metadata>, <f:viewParam> and <f:viewAction> be used for?
Communication in JSF 2.0 - Processing GET request parameters