Question

我试图在JSF中编写一些简单的登录页面，但我并不真正了解转换器类。我尝试登录时遇到此错误：

JSF - java.lang.NumberFormatException：对于输入字符串：＆＃34;＆＃34;

我的控制器类：

@ManagedBean(name="main")
@SessionScoped
@PersistenceContext(name = "persistence/LogicalName", unitName = "ProjectPU")
public class MainController {

private EntityManager em;
@Resource
private javax.transaction.UserTransaction utx;
@PersistenceUnit(unitName="ProjectPU")
private EntityManagerFactory emf;
/**
 * Creates a new instance of MainController
 */

Users user = new Users();

public Users getUser() {
    return user;
}

public void setUser(Users user) {
    this.user = user;
}

private EntityManager getEntityManager() 
{
    return emf.createEntityManager();
}

public MainController() {
}


public String signin() 
{
    EntityManager em = getEntityManager();

    TypedQuery<Users> query = em.createNamedQuery("Users.findByLogin", Users.class);

    query.setParameter("login", user.getLogin());
    Users result = null;
    try{
        result = query.getSingleResult();
    } catch(javax.persistence.NoResultException a){

    }
    if (result != null) {

        if(result.getPassword().equals(user.getPassword())){
        Util.getSession().setAttribute("login", user.getLogin());


        return "index.xhtml";
        } 

    } else {

        return "signin.xhtml";
    }

    return "index.xhtml";
}

public Object findUser(Integer id) {
    EntityManager em = getEntityManager();
try {
    Users u = (Users) em.find(Users.class, id);
    return u;
} finally {
    em.close();
}
}  
}

我的转换器类：

@FacesConverter("Converters.UsersConverter")
public class UsersConverter implements Converter
{

@Override
public Object getAsObject(FacesContext context, UIComponent component, String value) 
{
    if (!value.equals("null")) 
    {

        Integer id = new Integer(value);
        MainController controller = (MainController)        context.getApplication().getELResolver().getValue(
                                         context.getELContext(), null, "main");
        return controller.findUser(id);

    }
    else
    {
        return null;
    }
}

@Override
public String getAsString(FacesContext context, UIComponent component, Object value) 
{
    if (value == null) {
        return null;
    }

    if(value instanceof Users) 
    {
        Users u = (Users) value;
        return "" + u.getId();
    } 
    else 
    {
        throw new IllegalArgumentException("object:" + value + " of type:" + value.getClass().getName() + "; expected type: Users");
    }
}    
}

和我的观点（索引页面）：

<?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:ui="http://xmlns.jcp.org/jsf/facelets"
  xmlns:h="http://xmlns.jcp.org/jsf/html"
  xmlns:f="http://xmlns.jcp.org/jsf/core">
<h:head>
    <title>Facelet Title</title>
</h:head>
<h:body>
                <h:form>
                    <table>
                        <h:inputHidden value="#{main.user}" immediate="true"/>
                        <tr><td>Login:</td><td><h:inputText id="login" value="#  {main.user.login}"/></td></tr>
                        <tr><td>Password:</td><td><h:inputSecret id="password" value="#{main.user.password}"/></td></tr>
                    </table>
                    <h:commandButton id="submit" value="Signin" action="#{main.signin()}"/>
                </h:form>
</h:body>
</html>

我创建了数据库我有一个表用户和我添加了一个用户，我无法登录。在调试器上，我可以在两个方法中看到转换器中的空值（getasobject和getasstring）。

JSF - java.lang.NumberFormatException：对于输入字符串：＆＃34;＆＃34; - 转换器类

0 个答案: