Error when selecting data saved in BD via a <p:Selectonemenu>

Question

I’m having trouble loading a user’s data into the form.

Man selectOneMenu is loaded(correctly) with a list of guys however the TYPE object entered in the User record is not being selected during editing.

Summary: I have a user class and each user can be of various types. ( Admgeral/ Admgerencia / Admcompras / Userbasico / etc. ) I can register new users without problems but I’m having difficulty editing an existing record due to the "Selectonemenu" component that is not selecting the value saved in the database.

I made a reduced version of the problem to facilitate and assist others.

Java User Class.

@Entity
public class Usuario{
    @Id
    @GeneratedValue(generator="user_id_seq")
    @SequenceGenerator(name="user_id_seq",sequenceName="user_id_seq",allocationSize=1)
    private Integer id;
    private String nome;

    @OneToOne
    private Tipo tipo

    public Integer getId() {
       return this.id;
    }
    public void setId(Integer id) {
       this.id = id;
    }

    public Tipo getTipo() {
       return this.tipo;
    }
    public void setTipo(Tipo tipo) {
       this.tipo = tipo;
    }

    public String getNome(){
       return this.nome;
    }
    public void setNome(String nome) {
       this.nome = nome;
    }
}

Class Type.java

@Entity
public class Tipo{

 @GeneratedValue(generator="tipo_id_seq")
 @SequenceGenerator(name="tipo_id_seq",sequenceName="tipo_id_seq",allocationSize=1)
    private Integer id;
    private String nome;

    public Integer getId() {
       return this.id;
    }
    public void setId(Integer id) {
       this.id = id;
    }

    public String getNome(){
       return this.nome;
    }
    public void setNome(String nome) {
       this.nome = nome;
    }
}

View User.xhtml

<h:form id="form_user">
    <p:panelGrid columns="2">
        <p:outputLabel value="ID" />
        <p:inputText disabled="true" value="#{usuarioBean.usuario.id}" />

        <p:outputLabel value="Nome" />
        <p:inputText value="#{usuarioBean.usuario.nome}" />

        <p:outputLabel value="ID" />
        <p:selectOneMenu value="#{usuarioBean.usuario.tipo}" required="true">
             <f:selectItem itemLabel="Select" />
             <f:selectItems value="#{tipoBean.lista}" var="c" itemValue="#{c}" itemLabel="#{c.nome}" />
             <f:converter converterId="entityConverter"/>
        </p:selectOneMenu>
        <p:commandButton value="New" icon="fa fa-plus" update="form_user" action="#{usuarioBean.newRecord}" />
        <p:commandButton value="Save" icon="fa fa-save" update="form_user" action="#{usuarioBean.save}"/>
    </p:panelGrid>

    <p:dataTable var="user" value="#{usuarioBean.lista}">
        <h:outputText value="#{user.id}"/>
        <p:commandButton title="Edit" update="form_user" icon="fa fa-fw fa-edit" process="@this">
        <f:setPropertyActionListener target="#{usuarioBean.usuario}" value="#{user}" />
        </p:commandButton>

        <p:commandButton action="#{usuarioBean.removeRecord}" update="form_user" icon="fa fa-fw fa-trash" immediate="true">
            <f:setPropertyActionListener target="#{usuarioBean.usuario}" value="#{user}" />
        </p:commandButton>
    </p:dataTable>
</h:form>

Convert Entityconverter

@FacesConverter(value="entityConverter")
public class EntityConverter implements Converter {

    public Object getAsObject(FacesContext ctx, UIComponent component,
            String value) {
        if (value != null) {
            return component.getAttributes().get(value);
        }
        return null;
    }

    public String getAsString(FacesContext ctx, UIComponent component,
            Object obj) {
        if (obj != null && !"".equals(obj)) {
            String id;
            try {
                id = this.getId(getClazz(ctx, component), obj);
                if (id == null){
                    id = "";
                }
                id = id.trim();
                component.getAttributes().put(id, getClazz(ctx, component).cast(obj));
                return id;
            } catch (Exception e) {
                e.printStackTrace(); 
            }
        }
        return null;
    }

    private Class<?> getClazz(FacesContext facesContext, UIComponent component) {
        return component.getValueExpression("value").getType(
                facesContext.getELContext());
    }

    public String getId(Class<?> clazz, Object obj) throws SecurityException,
            NoSuchFieldException, IllegalArgumentException,
            IllegalAccessException {
        for (Field field : clazz.getDeclaredFields()) {
            if ((field.getAnnotation(Id.class)) != null) {
                Field privateField = clazz.getDeclaredField(field.getName());
                privateField.setAccessible(true);
                if (privateField.get(clazz.cast(obj)) != null) {
                    return (String)field.getType()
                            .cast(privateField.get(clazz.cast(obj))).toString();
                } else {
                    return null;
                }
            }
        }
        return null;
    }
}

Completion:

1 - My Selectonemenu is being populated with database data correctly

2 - After I started using the generic converter(Entityconverter) I can save the user record in the database.

3 - When I open the record for editing it does not load the type saved in the database in Selectonemenu.

What I’m doing wrong?

Answer 1

After analyzing a ready project using JPA/Hibernate I noticed that the classes had the equals and hash code method. That’s exactly what I hadn’t implemented and didn’t let Selectonemenu select my object.

Below is the method entered in the Type class.java

@Override
    public boolean equals(Object obj) {
        if (this == obj)
            return true;
        if (obj == null)
            return false;
        if (getClass() != obj.getClass())
            return false;
        Tipo other = (Tipo) obj;
        if (id == null) {
            if (other.id != null)
                return false;
        } else if (!id.equals(other.id))
            return false;
        return true;
    }