Bean could not be created on the Seam Project

[ekusnady]

Hello all,

i am a newbi in Seam-programming.
I already could make a Hello Seam on JBoss. But it's only the first step. I still have to learn many things.

Now i am trying to make an input Text where user can type a name and then beside this Input Text, the name they typed, will be shown.

So first,of course i make a java project named Bean.
My Bean.java is

 
package model; 

public class Bean {

     public String text;
     public Bean() {
          
     }
     public String getText() {
          return text;
     }
     public void setText(String text) {
          this.text = text;
     }
}

And i make a new .xhtml file named hello.xhtml. It looks like this

<!DOCTYPE composition PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<ui:composition xmlns="http://www.w3.org/1999/xhtml"
    xmlns:s="http://jboss.com/products/seam/taglib"
    xmlns:ui="http://java.sun.com/jsf/facelets"
    xmlns:f="http://java.sun.com/jsf/core"
    xmlns:h="http://java.sun.com/jsf/html"
    xmlns:rich="http://richfaces.org/rich"
    template="layout/template.xhtml"
                xmlns:a4j="http://richfaces.org/a4j">

    <ui:define name="body">

        <h1>Welcome to Seam!</h1>
        <rich:panel>
            <h:panelGrid columns="2">
                <h:graphicImage value="/img/seamlogo.png" alt="Seam logo"/>
                <s:div styleClass="info">
                   <h:commandButton value="Hello" size="50" style=" width : 129px; height : 60px;"/>
                   <h:inputText value="#{bean.text}"/>
                   <a4j:support event="onkeyup" reRender="rep"/>
                           <h:outputText value="#{bean.text}" id="rep"/>               
                </s:div>
            </h:panelGrid>
        </rich:panel>

    </ui:define>
</ui:composition>

And into my face-config.xml i add this code

 <managed-bean>
  <managed-bean-name>bean</managed-bean-name>
  <managed-bean-class>model.Bean</managed-bean-class>
  <managed-bean-scope>request</managed-bean-scope>
  <managed-property>
   <property-name>text</property-name>
   <property-class>java.lang.String</property-class>
   <value/>
  </managed-property>
 </managed-bean>

And i didn't add anything onto web.xml.

I deployed it...
But in the webbroser i got this :

An Error Occurred:
javax.faces.FacesException: Cant instantiate class: model.Bean.. model.Bean

Stack Trace

Component Tree

Scoped Variables

And in the console there was an error:
Managedbean bean could not be created.

Could anyone please help me?
I am really new here ..

It would be my pleasure to get any feedback from you.

Thank you

[asookazian]

change this:

<h:commandButton value="Hello" size="50" style=" width : 129px; height : 60px;"/>

to:

<h:commandButton value="Hello" action="#{foo.bar}" size="50" style=" width : 129px; height : 60px;"/>

In the Unified EL (expression language) above, 'foo' is the name of your Seam component and 'bar' is a business method (public) in your JavaBean or SFSB (if using SFSB, the method must be defined in your local interface).

so your backing bean would look something like this for a JavaBean:

@Name("foo")
public class Foo {
   public void bar() {
      //do stuff
   }
}

or this for a SFSB:

@Name("foo")
@Stateful
public class Foo implements FooLocal {
   public void bar() {
      //do stuff
   }

   @Remove
   public void destroy(){}
}

With JBoss EL, you can pass a param to the action method as well:

action="#{foo.bar(baz)}"

One of the purposes of Seam was to eliminate the XML in faces-config.xml you wrote.  You don't need to do that anymore when you use JSF/Seam/EJB3/JavaBean.

Look at the code for the hotel booking example very closely.  Conversation management/modeling and bijection are two of the most difficult aspects of Seam to learn...

Read one of the Seam books in their entirety (it's in your best interest :).