我如何解决JSF中的Target Unreachable错误

Question

再一次打扰我了，有人知道如何解决此错误/index.xhtml @ 17,95 value =“＃{user.firstname}”：无法到达目标，标识符'user'解析为空
我有geeter和seeter方法以及@ManagedBean和@SessionScoped，那么为什么netnet起作用？ tnx的答案。所以我有2个xhtml文件和一个java文件...问题可能在java文件中，但是我不知道为什么。

 <h:head>
    <title>JSf ragistration form</title>
</h:head>
<h:body>
    <h:form id="form">
        <h2>JSf registration app</h2>
        <h4>registration form</h4>
        <table>
            <tr>

                <td><h:outputLabel for="Fname">first name</h:outputLabel></td>
                <td><h:inputText id="first-id" value="#{user.firstname}" required="true"/></td>
            </tr>

            <tr>
                <td> <h:outputLabel for="Lname">last name</h:outputLabel></td>
                <td>
                    <h:inputText id="Last-id" value="#{user.lastname}" required="true"/>
                </td>


            </tr>

            <tr>
                <td> <h:outputLabel for="sex">Sex</h:outputLabel> </td>
                <td> <h:selectOneRadio id="sex-id" value="#{user.sex}" required="true"> 
                <f:selectItem itemLabel="male" itemValue="Male"/>
                <f:selectItem itemLabel="female" itemValue="Female" />
                </h:selectOneRadio>
                </td>



            </tr>

            <tr>

                <td> <h:outputLabel for="date">Date of birth</h:outputLabel></td>
                <td><h:inputText id="date-id" value="#{user.dat}" required="true">
                        <f:convertDateTime pattern="MM-dd-yy"/>
                    </h:inputText>
                    <br/>



                </td>


            </tr>

            <tr>
                <td>   <h:outputLabel id="email">Email</h:outputLabel></td>
                <td>
                    <h:inputText id="email-id" value="#{user.email}" required="true" validator="#{user.validateEmail(context, toValidate, value)}"/>


                </td>

            </tr>

            <tr>
                <td>   <h:outputLabel for="ser lev">Service lebel</h:outputLabel></td>
                <td>
                    <h:selectOneMenu id="sel-id" value="#{user.servicelevel}" required="true">
                        <f:selectItem itemLabel="madium" itemValue="Medium"/>
                        <f:selectItem itemLabel="basic" itemValue="basic"/>
                        <f:selectItem itemLabel="premium" itemValue="Premium"/>
                    </h:selectOneMenu>


                </td>



            </tr>


        </table>

        <h:commandButton value="Edit" action="register" />
        <h:commandButton value="Confirm" action="reg.xhtml" />
    </h:form>
</h:body>







public class User {
String firstname;
String lastname;
 Date dat;
 String sex;
 String email;
 String servicelevel="medium";

public void setFirstname(String firstname) {
    this.firstname = firstname;
}

public void setLastname(String lastname) {
    this.lastname = lastname;
}

public void setDat(Date dat) {
    this.dat = dat;
}

public void setSex(String sex) {
    this.sex = sex;
}

public void setEmail(String email) {
    this.email = email;
}

public void setServicelevel(String servicelevel) {
    this.servicelevel = servicelevel;
}

public String getFirstname() {
    return firstname;
}

public String getLastname() {
    return lastname;
}

public Date getDat() {
    return dat;
}

public String getSex() {
    return sex;
}

public String getEmail() {
    return email;
}

public String getServicelevel() {
    return servicelevel;
}


public void validateEmail(FacesContext context,UIComponent toValidate,Object value) throws ValidatorException
{
    String emailstr=(String)value;
    if(-1==emailstr.indexOf("@"))
    {
        FacesMessage msg=new FacesMessage("invalid email addres");
        throw new ValidatorException(msg);


    }


}

public String addConfirmedUser()
{
    boolean aded=true;
    FacesMessage done=null;
    String outcome=null;

    if(aded)
    {
        done=new FacesMessage("sucesfuly added new user");
        outcome="done";

    }
    else
    {
         done=new FacesMessage("failed to add new user");
         outcome="reigster";
    }

    FacesContext.getCurrentInstance().addMessage(null, done);
    return outcome;
}

}

 <h:head>
    <title>user comformation</title>
</h:head>
<h:body>
    <table>
        <tr>
            <td>  <b> First name: </b></td>
            <td> <h:outputText value="#{user.firstname}"/><br/></td>

         </tr>

        <tr>
            <td>  <b> last name: </b></td>
            <td> <h:outputText value="#{user.lastname}"/><br/></td>

         </tr>


        <tr>
            <td>  <b> sex </b></td>
            <td> <h:outputText value="#{user.sex}"/><br/></td>

         </tr>


        <tr>
            <td>  <b> date: </b></td>
            <td> <h:outputText value="#{user.dat}"/><br/></td>

         </tr>

        <tr>
            <td>  <b> EMAIL: </b></td>
            <td> <h:outputText value="#{user.email}"/><br/></td>

         </tr>

        <tr>
            <td>  <b> service level </b></td>
            <td> <h:outputText value="#{user.servicelevel}"/><br/></td>

         </tr>




    </table>

</h:body>