Bean没有在EJB 3.1中注入,只有这个bean有这种行为

Question

1和JSF 2.0 + primefaces很酷:D

我有这个验证器,但我不能正确地注入持久性单元.

所有其他bean都正常工作,这是唯一没有的,它给了我一个Nullpointer roleFacade

注入验证器是非法的吗？是否在生命周期中过早？它能是什么？

谢谢 !

import javax.ejb.EJB;
import javax.ejb.Stateless;
import javax.faces.component.UIComponent;
import javax.faces.context.FacesContext;
import javax.faces.convert.Converter;
import javax.faces.convert.FacesConverter;


@FacesConverter("rolesConverter")
@Stateless
public class RolesConverter implements Converter{

@EJB
private RoleFacade roleFacade;

@Override
public Object getAsObject(FacesContext context, UIComponent component, String value) {
        Roles role = null;
        if ((value != null) && (!value.equals(""))) {       
             role = roleFacade.find(Long.valueOf(value));       
        }
        return role;
}

@Override
public String getAsString(FacesContext context, UIComponent component, Object value) {
        Integer retorno = null;
        if (!(value == null)) {
            Roles role = new Roles();
            role = (Roles) value;
            retorno = role.getId();
        }
        return retorno.toString();
}

}

和门面

import java.util.List;
import javax.ejb.Stateless;
import javax.persistence.EntityManager;
import javax.persistence.PersistenceContext;
import javax.persistence.PersistenceContextType;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

@Stateless
public class RoleFacade extends AbstractFacade<Roles> {


@PersistenceContext(unitName = "br.com.cflex.itm-PU", type= PersistenceContextType.TRANSACTION)    
private EntityManager em;

private static Logger log = LoggerFactory.getLogger(RoleFacade.class);

@Override
protected EntityManager getEntityManager() {
    return em;
}

public RoleFacade() {
    super(Roles.class);
}

public RoleFacade(EntityManager em) {
    super(Roles.class);
    this.em = em;
}

public List<Roles> getListOfRoles(){
    log.debug("Calling method 'RoleFacade: List getListOfRoles()'");
    List<Roles> list = getEntityManager().createNamedQuery("Roles.findAll").getResultList();        
   return list;
}

}

Answer 1

你可以做到,你只是做错了.

试试这个:

import java.io.Serializable;
import javax.ejb.EJB;
import javax.ejb.Stateless;
import javax.enterprise.context.RequestScoped
import javax.faces.component.UIComponent;
import javax.faces.context.FacesContext;
import javax.faces.convert.Converter;
import javax.faces.convert.FacesConverter;
import javax.inject.Named;


@Named("rolesConverter")
@RequestScoped
public class RolesConverter implements Converter, Serializable {

@EJB
private RoleFacade roleFacade;

@Override
public Object getAsObject(FacesContext context, UIComponent component, String value) {
        Roles role = null;
        if ((value != null) && (!value.equals(""))) {       
             role = roleFacade.find(Long.valueOf(value));       
        }
        return role;
}

@Override
public String getAsString(FacesContext context, UIComponent component, Object value) {
        Integer retorno = null;
        if (!(value == null)) {
            Roles role = new Roles();
            role = (Roles) value;
            retorno = role.getId();
        }
        return retorno.toString();
}

在你的xhtml中,使用converter="#{rolesConverter}".当然,我假设你正在使用CDI.

顺便说一句,PrimeFaces很棒.:)