Private/scoped variable in JSF2/Facelets <ui:component>? - jsf

I might not be thinking correctly in terms of visual components in JSF, but I guess that's part of my question. My question is around the seeming lack of scope around variables declared within JSF <ui:component> implementations.
So, say I have /resources/comp/myPanel.xhtml:
<?xml version="1.0" encoding="UTF-8" ?>
<ui:component xmlns="http://www.w3.org/1999/xhtml"
xmlns:h="http://java.sun.com/jsf/html"
xmlns:f="http://java.sun.com/jsf/core"
xmlns:ui="http://java.sun.com/jsf/facelets"
xmlns:c="http://java.sun.com/jsp/jstl/core"
xmlns:cc="http://java.sun.com/jsf/composite">
<cc:interface>
</cc:interface>
<cc:implementation>
<f:loadBundle var="bundle" basename="panelOnly.bundle" />
<h:outputText value="#{bundle.myText}" />
</cc:implementation>
</ui:component>
And there is a resource bundle that gets loaded in that component, panelOnly/bundle.properties:
myText = This is a panel resource
And then I have a page that places the myPanel component, mainPage.xhtml:
<?xml version="1.0" encoding="UTF-8" ?>
<html xmlns="http://www.w3.org/1999/xhtml"
xmlns:h="http://java.sun.com/jsf/html"
xmlns:f="http://java.sun.com/jsf/core"
xmlns:ui="http://java.sun.com/jsf/facelets"
xmlns:comp="http://java.sun.com/jsf/composite/comp">
<h:body>
<f:view>
<f:loadBundle basename="mainPage.bundle" var="bundle" />
<comp:myPanel />
<h:outputText value="#{bundle.myText}" />
</f:view>
</h:body>
</html>
and there is a resource bundle that gets loaded in the main page, mainPage/bundle.properties:
myText = This is a main page resource
Now, I would assume that my page should render as:
This is a panel resource
This is a main page resource
But, instead, I get:
This is a panel resource
This is a panel resource
And I assume that is because I clobbered what the "bundle" symbol refers to in my component so that when the mainPage.xhtml tries to resolve that value, it looks to the component's "bundle" object and not the original mainPage's.
My workaround to date has been to just use unique named variables within my components that would never clash with variables on my main pages. But I would prefer if there was a way to coax JSF to recognize anything declared in my component as locally scoped variables and not clobber the caller's symbols.
I think there are and other tags that one can use to make locally scoped variables under #{cc.attrs...}. If you could enumerate my local scoping options in your answer, that would be very helpful. I suspect my <f:loadBundle> is a special case, and maybe there isn't a workaround for that one as it was not designed with <ui:component> in mind.
Thanks!
P.S. I'm running Mojarra 2.1.1 (FCS 20110408)
(edited for formatting and copy and paste bugs 6/15/2011)

Unfortunately, that's how <f:loadBundle> works. It's an one-time setting for the entire view. And any subsequent <f:loadBundle> calls in the same view will just override the previous one.
Your best bet is to manage it by a backing component.
<cc:interface componentType="myPanel">
with
#FacesComponent(value="myPanel")
public class MyPanel extends UIComponentBase implements NamingContainer {
private ResourceBundle bundle;
public MyPanel() {
bundle = ResourceBundle.getBundle("panelOnly.bundle",
FacesContext.getCurrentInstance().getViewRoot().getLocale());
}
#Override
public String getFamily() {
return "javax.faces.NamingContainer";
}
public ResourceBundle getBundle() {
return bundle;
}
}
which can be used as
<cc:implementation>
<h:outputText value="#{cc.bundle.myText}" />
</cc:implementation>

Related

Does the component-type name needs to be unique for custom components?

I am new to Custom components topic starting with JSF 2.2
However, I am first considering the case with JSF2.0
Consider the snippet:
#FacesComponent(value = "components.WelcomeComponent1", createTag = true)
public class WelcomeComponent extends UIComponentBase {
}
Do notice value = "components.WelcomeComponent1"
referencing it in the UI wireframe-
<html xmlns="http://www.w3.org/1999/xhtml"
xmlns:h="http://xmlns.jcp.org/jsf/html"
xmlns:t="http://xmlns.jcp.org/jsf/component">
<h:head>
<title></title>
</h:head>
<h:body>
<t:welcomeComponent value="Welcome" to="Rafael Nadal"/>
</h:body>
</html>
Consider the second case with the same name of the class as in first case but in a different package with a different component-type name:
#FacesComponent("components.WelcomeComponent")
public class WelcomeComponent extends UIComponentBase {
// code goes here
}
Do notice the "components.WelcomeComponent"
taglib.xml in WEB_INF
<namespace>http://atp.welcome.org/welcome</namespace>
<tag>
<tag-name>welcome</tag-name>
<component>
<component-type>components.WelcomeComponent</component-type>
</component>
<attribute>
<name>id</name>
<type>java.lang.String</type>
<description>Component id</description>
<required>false</required>
</attribute>
</tag>
</facelet-taglib>
and referencing the latter -
<html xmlns="http://www.w3.org/1999/xhtml"
xmlns:h="http://xmlns.jcp.org/jsf/html"
xmlns:t="http://atp.welcome.org/welcome">
<h:head>
<title></title>
</h:head>
<h:body>
<t:welcome value="Welcome" to=""/>
</h:body>
</html>
Both of the above examples are part of the same web app & work fine.
However if I change the component-type name in the second case to make it the same as in first case,
#FacesComponent("components.WelcomeComponent1")
I do get-
Warning: This page calls for XML namespace
http://xmlns.jcp.org/jsf/component declared with prefix t but no
taglibrary exists for that namespace
Clearly the entry/tag declared in taglib.xml is preferred.
So, the component-type name needs to be unique in each case. Right?
I know it very well that the namespace http://xmlns.jcp.org/jsf/component was introduced with JSF2.2.
Short answer is yes, it should be unique. JSF thinks of it as a name for your custom component (in the similar way as a #ManagedBean). Basically, component-type allows Application instance to create new instances of UIComponent subclasses (your and every other custom component) by using defined component-type and createComponent() method.

Value expressions still evaluated despite ui:fragment rendered="false"

I have bean:
class Property{
private String type;
private Date value;
//getters and setters
}
also have block of code on page:
<ui:fragment rendered="#{property.type eq 'checkbox'}">
<ui:include src="checkbox.xhtml">
<ui:param name="property" value="#{property}"/>
</ui:include>
</ui:fragment>
checkbox.xhtml:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml"
xmlns:h="http://java.sun.com/jsf/html"
xmlns:ui="http://java.sun.com/jsf/facelets"
xmlns:f="http://java.sun.com/jsf/core">
<body>
<ui:composition>
<h:selectBooleanCheckbox value="#{property.value}"/>
</ui:composition>
</body>
</html>
The condition #{property.type eq 'checkbox'} = false
But I get next exception:
javax.servlet.ServletException: checkBox.xhtml value="#{property.value}": Cannot convert 01.11.02 0:00 of type class java.util.Date to class java.lang.Boolean
I expect if the attribute rendered=false in ui:include, then this block will not be processed.
<ui:fragment rendered> prevents it from rendering the HTML output, but it doesn't prevent it from ending up in JSF component tree and being eligible for state saving.
Use <c:if test> instead. It runs during view build time instead of view render time and thus the whole bunch won't end up in JSF component tree at all.
Or, if you have this all inside an <ui:repeat var="property">, and you are using Mojarra, then upgrade to at least 2.1.29 or 2.2.7 wherein this state saving bug was fixed.
See also:
JSTL in JSF2 Facelets... makes sense?
PropertyNotFoundException on conditionally rendered subclasses in ui:repeat

Saving and reusing tag definition in PrimeFaces

Let's say I have the following construct polluting the simplicity of my JSF code in many places:
<p:calendar id="decisionDate"
effect="explode"
yearRange="2000:2100"
pattern="MM/dd/yyyy"
navigator="true" display="inline"
value=""
label="Decision Date"
maxlength="10"
size="20">
<f:convertDateTime pattern="MM/dd/yyyy" />
</p:calendar>
As can be seen, this has nine (9) attributes and a nested tag. This is an awful amount of tedious detail to consume with your eye.
Is there a way I can reuse PrimeFaces tags in a similar way as CSS: to save a complex tag definition as <px:myCalendar/> with the above parameters minus the ID ones, which should be set for each instance of use nonetheless, where px would be my namespace and then each time I need to invoke it, I would just say <px:myCalendar id="uniqueCalID"/> and ... BOOM ... there goes all the repeated clutter?
POST ANSWER EDIT: Check out this tutorial
You can define composite component. It is defined with xhtml+ jsf namespaces and, but in your case it is unnesessary, backing component, which is java class, instantiated for every composite component usage.
Within composite component interface you can define attributes, which vary its behaviour. And in implementation you then can insert needed primefaces' component with some hardcoded attributes and some passed from your composite component invocation.
Consider this tutorial: https://docs.oracle.com/javaee/6/tutorial/doc/giqzr.html
Example
Composite component is resource, so we put it below /resources folder. Let's create subfolder /resources/myCompositeComponents and create xhtml file myCalendar.xhtml there. It will be our composite component. Basically, it is xhtml file with additional namespace xmlns:cc="http://java.sun.com/jsf/composite". Here is the code. You can notice two elements: <cc:interface> and <cc:implementation>. And <cc:attribute> element inside the <cc:interface> is the input of our composite component.
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml"
xmlns:f="http://xmlns.jcp.org/jsf/core"
xmlns:cc="http://java.sun.com/jsf/composite"
xmlns:p="http://primefaces.org/ui" xmlns:h="http://java.sun.com/jsf/html">
<cc:interface>
<cc:attribute name="label" default="Decision Date"/>
</cc:interface>
<cc:implementation>
<h2>#{cc.clientId}</h2>
<h:outputLabel
id="Label"
value="#{cc.attrs.label}"/>
<p:calendar id="Calendar"
effect="explode"
yearRange="2000:2100"
pattern="MM/dd/yyyy"
navigator="true" display="inline"
value=""
label="Label"
maxlength="10"
size="20">
<f:convertDateTime pattern="MM/dd/yyyy" />
</p:calendar>
</cc:implementation>
</html>
Then, let's use it. To be able to declare our brand new component we will put additional namespace into the using page: xmlns:my="http://java.sun.com/jsf/composite/myCompositeComponents". The last part of the namespace uri corresponds to the folder under /resources, where composite component lives. Give it any prefix you like. Here is source code:
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE html
PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml"
xmlns:h="http://java.sun.com/jsf/html"
xmlns:my="http://java.sun.com/jsf/composite/myCompositeComponents">
<h:head>
<title>Simple JSF Facelets page</title>
</h:head>
<h:body>
<my:myCalendar id="LetsUseIt" label="MyLabel"/>
</h:body>
</html>
Have a notice of attribute "label" - that very attribute, that is declared in the "interface" element.
This is quite basic usecase, though it will help in your situation. More complex scenarios include passing typed attributes and implementing backing component - java class, instantiated every time the component is used.

param reference to bean not being passed into composite component

i'm having a bit of trouble with a composite component in JSF 2.1 vanilla (on glassfish 3.1). the simplified version of my problem is here:
[composite component]
<?xml version='1.0' encoding='UTF-8' ?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml"
xmlns:f="http://java.sun.com/jsf/core"
xmlns:c="http://java.sun.com/jsp/jstl/core"
xmlns:ui="http://java.sun.com/jsf/facelets"
xmlns:h="http://java.sun.com/jsf/html"
xmlns:p="http://primefaces.org/ui"
xmlns:cc="http://java.sun.com/jsf/composite">
<!-- INTERFACE -->
<cc:interface>
<cc:attribute name="value" required="true"/>
<cc:attribute name="title" required="false" default=""/>
<cc:editableValueHolder name="inputTarget" targets="labeledInputField"/>
</cc:interface>
<!-- IMPLEMENTATION -->
<cc:implementation>
<p:inputText id="labeledInputField"
label="#{cc.attrs.title}"
value="#{cc.attrs.value}"
title="#{cc.attrs.title}">
<cc:insertChildren/>
</p:inputText>
</cc:implementation>
</html>
[implemented in]
<!-- thisPerson is passed in via ui:param to the facelet containing this code.
it works in other (non-composite) components on the page -->
<comp:labeledInputText
id="baseUsername"
value="#{controller.username}"
title="#{bundle.Username}">
<f:validator for="inputTarget" binding="#{thisPerson.usernameValidator}"/>
<f:converter for="inputTarget" converterId="#{whiteSpaceTrimConverter}"/>
</comp:labeledInputText>
the problem is, the "thisPerson.usernameValidator" is evaluating to NULL, which then causes the com.sun.faces.facelets.tag.jsf.ValidatorTagHandlerDelegateImpl to then skip to the code that attempts to load the validator by "validatorID" which is not set because we're trying to send in the validator by "binding". is there a way to get the composite to evaluate the ui:param value, or a workaround that does not require reworking the validator (it's a huge anti-pattern and i don't have time to reverse the damage right now). assume the validator HAS to come in via binding.
i know the composite works because in a different facelet, i have the validator binding against a concrete bean reference, rather than a "soft" reference, and it works like a champ.
TIA
Without knowing your exact JSF implementation, I am going to assume Mojarra, you may be running into the following known bug.
http://java.net/jira/browse/JAVASERVERFACES-2040
Regardless if this is your exact problem or not, you can try to disable partial state saving and see if this resolves your issue. If it does then that means that you are facing this issue, which apparently was (fixed?) in later versions of Mojarra.
Another possibility would be to simply use renderFacet instead of insertChildren and insert your validators in the form of a facet.

Why <f:validateBean /> won't work?

I use JSF 2.0, hibernate-validator4.2.jar validation-api.jar tomcat and Eclipse.
I put #Size(min=3, message="xxx") annotation in a #ManagedBean and <f:validateBean /> between <h:inputText value="#{user.name}"></h:inputText>
When I try to run the project i get this error...
exception
javax.servlet.ServletException: Expression Error: Named Object: javax.faces.Bean not found.
javax.faces.webapp.FacesServlet.service(FacesServlet.java:606)
root cause
javax.faces.FacesException: Expression Error: Named Object: javax.faces.Bean not found.
com.sun.faces.application.ApplicationImpl.createValidator(ApplicationImpl.java:1593)
com.sun.faces.facelets.tag.jsf.ValidatorTagHandlerDelegateImpl.createValidator(ValidatorTagHandlerDelegateImpl.java:244)
com.sun.faces.facelets.tag.jsf.ValidatorTagHandlerDelegateImpl.applyAttachedObject(ValidatorTagHandlerDelegateImpl.java:132)
com.sun.faces.facelets.tag.jsf.ValidatorTagHandlerDelegateImpl.applyNested(ValidatorTagHandlerDelegateImpl.java:211)
com.sun.faces.facelets.tag.jsf.ValidatorTagHandlerDelegateImpl.apply(ValidatorTagHandlerDelegateImpl.java:87)
javax.faces.view.facelets.DelegatingMetaTagHandler.apply(DelegatingMetaTagHandler.java:120)
javax.faces.view.facelets.DelegatingMetaTagHandler.applyNextHandler(DelegatingMetaTagHandler.java:137)
why? (this only appears when i put tag)
User.java
import java.io.Serializable;
import javax.faces.bean.ManagedBean;
import javax.faces.bean.SessionScoped;
import javax.validation.constraints.Size;
#ManagedBean(name="user")
#SessionScoped
public class User{
#Size(min=3, message="At least 3 characters!")
private String name;
public String getName() {
return nume;
}
public void setName(String name){
this.name=name;
}
}
adduser.xhtml
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml"
xmlns:ui="http://java.sun.com/jsf/facelets"
xmlns:h="http://java.sun.com/jsf/html"
xmlns:f="http://java.sun.com/jsf/core">
<ui:composition template="/templates/master_layout.xhtml">
<ui:define name="text_header" >Panou de control: Adauga user </ui:define>
<ui:define name="content">
<h:panelGrid columns="3">
<h:outputText value="Name"></h:outputText>
<h:inputText value="#{user.name}">
<f:validateBean />
</h:inputText>
<h:commandButton value="Inregistreaza" action="index.xhtml"></h:commandButton>
</h:panelGrid>
</ui:define>
</ui:composition>
</html>
It should work perfectly fine, although the empty <f:validateBean/> tag is entirely superfluous in this context. It's supposed to be used to "finetune" validation more, such as grouping of validation and/or disabling the implicit bean validation on a per-input basis by specifying the desired tag attributes. You have however no attributes on that tag, so just remove that tag altogether. On a default JSF 2 + JSR 303 project setup, it's supposed to kick in fully transparently without adding more JSF tags whenever there's a JSR 303 annotation on the property such as #Size and likes.
But I don't think that removing the tag will solve this particular exception. Your problem lies thus deeper. This validator is supposed to be auto-registered on startup. However, the exception basically tells that the validator is not registered at all. With the information given so far, it's not possible to give a targeted answer. I can think of the following possible causes:
There's a bug in the JSF implementation which you're using. Upgrade it to a newer version.
You have multiple JSF libraries of different versions in your classpath. Cleanup it.
The faces-config.xml root declaration is not declared conform JSF 2.x. Fix it.

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