I need to create a callback for <h:commandButton> while as a parameter I need to pass an argument that is string-concatenated with an external parameter id:
I tried nesting an EL expression something like this:
<h:commandButton ... action="#{someController.doSomething('#{id}SomeTableId')}" />
However this failed with an EL exception. What is a right syntax/approach to do this?
If you're already on EL 3.0 (Java EE 7; WildFly, Tomcat 8, GlassFish 4, etc), then you could use the new += operator for this:
<h:commandButton ... action="#{someController.doSomething(id += 'SomeTableId')}" />
If you're however not on EL 3.0 yet, and the left hand is a genuine java.lang.String instance (and thus not e.g. java.lang.Long), then use EL 2.2 capability of invoking direct methods with arguments, which you then apply on String#concat():
<h:commandButton ... action="#{someController.doSomething(id.concat('SomeTableId'))}" />
Or if you're not on EL 2.2 yet, then use JSTL <c:set> to create a new EL variable with the concatenated values just inlined in value:
<c:set var="tableId" value="#{id}SomeTableId" />
<h:commandButton ... action="#{someController.doSomething(tableId)}" />
See also:
String concatenation in EL for dynamic ResourceBundle key
Related
I need to create a callback for <h:commandButton> while as a parameter I need to pass an argument that is string-concatenated with an external parameter id:
I tried nesting an EL expression something like this:
<h:commandButton ... action="#{someController.doSomething('#{id}SomeTableId')}" />
However this failed with an EL exception. What is a right syntax/approach to do this?
If you're already on EL 3.0 (Java EE 7; WildFly, Tomcat 8, GlassFish 4, etc), then you could use the new += operator for this:
<h:commandButton ... action="#{someController.doSomething(id += 'SomeTableId')}" />
If you're however not on EL 3.0 yet, and the left hand is a genuine java.lang.String instance (and thus not e.g. java.lang.Long), then use EL 2.2 capability of invoking direct methods with arguments, which you then apply on String#concat():
<h:commandButton ... action="#{someController.doSomething(id.concat('SomeTableId'))}" />
Or if you're not on EL 2.2 yet, then use JSTL <c:set> to create a new EL variable with the concatenated values just inlined in value:
<c:set var="tableId" value="#{id}SomeTableId" />
<h:commandButton ... action="#{someController.doSomething(tableId)}" />
See also:
String concatenation in EL for dynamic ResourceBundle key
Is something like that possibile to build the MethodName with a variable value?
<c:forEach value="#{db.pojo.classList}" var="v">
<c:forEach items="#{db.pojo.methodNamesList}" var="o">
<c:set var="superman" value="#{o}" />
#{v.[superman]}
</c:forEach>
</c:forEach >
... database.entity.list is a List of Generic classes.
List<?> list..
I can use the generic class if i know the Methodname.
<c:forEach value="#{db.pojo.classList}" var="v">
#{v.value}
</c:forEach >
#{v.[superman]}
Punch that period.
#{v[superman]}
That <c:set> is unnecessary, by the way.
#{v[o]}
I would only use more self-documenting variable names though. E.g.
#{bean[property]}
#{entity[field]}
See also:
Our EL wiki page
I need to create a callback for <h:commandButton> while as a parameter I need to pass an argument that is string-concatenated with an external parameter id:
I tried nesting an EL expression something like this:
<h:commandButton ... action="#{someController.doSomething('#{id}SomeTableId')}" />
However this failed with an EL exception. What is a right syntax/approach to do this?
If you're already on EL 3.0 (Java EE 7; WildFly, Tomcat 8, GlassFish 4, etc), then you could use the new += operator for this:
<h:commandButton ... action="#{someController.doSomething(id += 'SomeTableId')}" />
If you're however not on EL 3.0 yet, and the left hand is a genuine java.lang.String instance (and thus not e.g. java.lang.Long), then use EL 2.2 capability of invoking direct methods with arguments, which you then apply on String#concat():
<h:commandButton ... action="#{someController.doSomething(id.concat('SomeTableId'))}" />
Or if you're not on EL 2.2 yet, then use JSTL <c:set> to create a new EL variable with the concatenated values just inlined in value:
<c:set var="tableId" value="#{id}SomeTableId" />
<h:commandButton ... action="#{someController.doSomething(tableId)}" />
See also:
String concatenation in EL for dynamic ResourceBundle key
I'm working with JSF and JSTL, the code above doesn't work!
<ui:repeat var="reponse" value="#{gPost.reponses}"> UserLogin : #{reponse.utilisateur.login}
<c:if test="${reponse.utilisateur.login eq 'X'}">
Utilisateur equivalent X
</c:if>
</ui:repeat>
This code iterate, i have two element to be iterated, the output is this :
UserLogin : Y
UserLogin : X
It must be :
UserLogin : Y
UserLogin : X
Utilisateur equivalent X
The tag <c:if test="${reponse.utilisateur.login eq 'X'}"> is not correct?
JSTL tags like <c:if> runs during view build time, while JSF components like <ui:repeat> runs during view render time. So, with your code given so far, the #{reponse} is not available while JSTL is running, because <ui:repeat> hasn't run. You need a normal JSF component with rendered attribute instead.
<h:panelGroup rendered="#{reponse.utilisateur.login eq 'X'}">
Utilisateur equivalent X
</h:panelGroup>
See also:
JSTL in JSF2 Facelets... makes sense?
I have a question about outputing a list of objects as a comma separated list in JSF.
Let's say:
public class SomeObj {
private String name;
... constructors, getters and setters ...
}
and List<SomeObj>:
List<SomeObj> lst = new ArrayList<SomeObj>();
lst.add(new SomeObj("NameA"));
lst.add(new SomeObj("NameB"));
lst.add(new SomeObj("NameC"));
to output it as a listbox I can use this code:
<h:selectManyListbox id="id1"
value="#{listHolder.selectedList}">
<s:selectItems value="#{listHolder.lst}"
var="someObj"
label="#{someObj.name}"/>
<s:convertEntity />
</h:selectManyListbox>
But what is the easiest way to output the list as is, comma seperated ? Like this:
NameA, NameB, NameC
Should I use JSTL <c:forEach/> or may be the <s:selectItems/> tag can also be used ?
Given a List<Person> persons where Person has a name property,
If you're already on Java EE 7 with EL 3.0, then use EL stream API.
#{bean.persons.stream().map(p -> p.name).reduce((p1, p2) -> p1 += ', ' += p2).get()}
If you're not on EL 3.0 yet, but have JSF 2.x at hands, then use Facelets <ui:repeat>.
<ui:repeat value="#{bean.persons}" var="person" varStatus="loop">
#{person.name}#{not loop.last ? ', ' : ''}
</ui:repeat>
Or if you're still on jurassic JSP, use JSTL <c:forEach>.
<c:forEach items="#{bean.persons}" var="person" varStatus="loop">
${person.name}${not loop.last ? ', ' : ''}
</c:forEach>
See also:
How iterate over List<T> and render each item in JSF Facelets
JSTL in JSF2 Facelets... makes sense?
use <ui:repeat> (from facelets). It's similar to c:forEach
Or pre-compute the comma-separated string in the managed bean, and obtain it via a getter.
If you can't use varStatus because you're stuck with using JSF 1.2, you can do:
<ui:repeat value="#{listHolder.lst}" var="someObj">#{someObj != listHolder.lst[0] ? ',' : ''}
#{someObj.name}</ui:repeat>
The absence of whitespace around the EL-expressions is deliberate, we don't want a space to appear there in the rendered HTML.