I think I have run into a bug in Mojarra 2.1.0. Maybe I missed something but damned if I can see it.
I rely a lot of @ViewScoped beans to save state whilst the browser does a lot of AJAX to the server. I find when I use certain tags, the @ViewScoped bean starts getting re-instantiated when it shouldn't be. Here is my test case backing bean:
/*
* TestStuff.java
*/
package test;
import java.io.Serializable;
import java.util.Arrays;
import java.util.List;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.faces.bean.ManagedBean;
import javax.faces.bean.ViewScoped;
import javax.faces.event.ActionEvent;
/**
* Backing bean for test.xhtml -- working out AJAX/SVG connection
*
*/
@ManagedBean
@ViewScoped
public class TestStuff implements Serializable {
private int counter = 0;
public TestStuff() {
log("TestStuff(): {0}", this);
}
public String getRandomNumber() {
int i = (int) (Math.random() * 1000000.0);
return String.format("%d", i);
}
public int getCounter() { return counter; }
public List<String> getStuff() {
return Arrays.asList("big", "bad", "wolf");
}
public void pushButton(ActionEvent evt) {
log("TestStuff.pushButton({0}): {1}",
new Object[] { evt, ++counter });
}
}
And here is the JSF Facelets page that uses it:
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml"
xmlns:h="http://java.sun.com/jsf/html"
xmlns:p="http://primefaces.prime.com.tr/ui"
xmlns:ui="http://java.sun.com/jsf/facelets"
xmlns:f="http://java.sun.com/jsf/core"
xmlns:c="http://java.sun.com/jsp/jstl/core">
<h:head>
<title>Test Page</title>
</h:head>
<h:body>
<h1>Test Page</h1>
<p>If you are reading this text, the server
is not properly configured.</p>
<ui:composition id="compRoot" template="/template5.xhtml">
<ui:define name="content">
<h1>Test</h1>
<h:form id="formTest">
<p:commandButton value="Do Me"
actionListener="#{testStuff.pushButton}"
update="testUpdate" />
<p:panel id="testUpdate" >
<h:outputText value="Random output is: " />
<h:outputText
value="#{testStuff.randomNumber}"
/>
<h:outputText value=" Counter is: "/>
<h:outputText
value="#{testStuff.counter}"
/>
</p:panel>
<h:panelGrid columns="5" border="1" >
<c:forEach items="#{testStuff.stuff}" var="x">
<h:outputText value="#{x}" />
</c:forEach>
</h:panelGrid>
</h:form>
</ui:define>
</ui:composition>
</h:body>
</html>
So here is what goes wrong. When you click on the "Do Me" command button, a new instance of the backing bean gets created each time, just as if it were a @RequestScoped bean. I can see this via the log() call in the constructor.
If you change the bean to @SessionScoped, this doesn't happen. You get one instance of the bean no matter how many times the button is clicked.
HOWEVER -- if you leave it as @ViewScoped, and you take out the c:foreach element and its content, it now no longer re-instantiates the bean each click. In other words it now works as expected.
Is this a mojarra bug or am I doing something wrong here?
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