Question

I want to fill a simple h:datatable tag with some values from a database. But i get an exception and i cant find what is the reason:

java.lang.NumberFormatException: For input string: “url”

This is how i create the datatable:

<h:form>        
    <h:dataTable value="#{managementBB.retrieveRecords()}" var="record">
    <h:column>
        <f:facet name="header">URL</f:facet>
        #{record.url}
    </h:column>
    <h:column>
        <f:facet name="header">Submition date</f:facet>
        #{record.submitionDate}
    </h:column>
    <h:column>
        <f:facet name="header">Unacceptable</f:facet>
        #{record.unnaceptableContent}
    </h:column>
    <h:column>
        <f:facet name="header">Option</f:facet>
        Something
    </h:column>
    </h:dataTable>
</h:form>

This is the backing bean behind this page:

@Named("managementBB")
@SessionScoped
public class ManagementBB implements Serializable{

    @EJB
    private ILinkManagerEJB linkManagerEJB;

    public List<Record> retrieveRecords() {     
            return linkManagerEJB.retrieveRecords();
    }
}

This is the EJB that accesses the database to get the data:

@Stateless(name = "ejbs/LinkManagerEJB")
public class LinkManagerEJB implements ILinkManagerEJB {

    @PersistenceContext
    private EntityManager entityManager;

    public List<Record> retrieveRecords() {
        Query allRecords = entityManager.createNamedQuery("allrecordinfo");      
        return (List<Record>) allRecords.getResultList();
    }
}

And finally this is the JPA entity that represents a row in the database:

@Entity
@NamedQueries({@NamedQuery(name = "allrecordinfo",
   query = "SELECT r.url, r.submitionDate, r.unnaceptableContent FROM Record r")})
public class Record {

    @Id
    @GeneratedValue
    private long id;
    @Column(nullable = false)
    private String url;
    @Column(nullable = false)
    private String submitionDate;
    @Column(nullable = false)
    private boolean unnaceptableContent;

    //Get set methods ...
}

As you see it looks simple, and I’ve done this before but now I am confused, I don’t know why is not working. Could you help me find my error?

Note: I am pretty confident that the query syntax is ok (I tested it in eclipse’s scrapbook)

Answer 1

The query is not correct.

@NamedQueries({ @NamedQuery(name = "allrecordinfo", query = "SELECT r FROM Record r") })
@Entity
public class Record {
}