JSF(managed) beans, can not work with JPA

[Jason Marlyn]

hi folks, I'm new in JSF
I developed a JSF application,
application is about a small library
okay, admin users can add new book to system(DB)
I do it with a method in a managed bean, but
some problems are here
codes
the bookAdd.jsp page (it's Okay)

<%@taglib prefix="f" uri="http://java.sun.com/jsf/core" %>
<%@taglib prefix="h" uri="http://java.sun.com/jsf/html" %>
<f:subview id="addBook" rendered="#{user.access}">
    <h:form id="addForm">
        <h:panelGrid columns="3">
            <h:outputLabel for="name"><h:outputText value="Name"/></h:outputLabel>
            <h:inputText id="name" value="#{bookAdd.name}"><f:validateLength minimum="1" maximum="64"/></h:inputText>
            <h:message for="name"/>
            <h:outputLabel for="price"><h:outputText value="Price"/></h:outputLabel>
            <h:inputText id="price" value="#{bookAdd.price}"><f:validateDoubleRange maximum="10000" minimum="0"/></h:inputText>
            <h:message for="price"/><h:panelGroup/>
            <h:commandButton value="add" actionListener="#{bookAdd.addBook}"/><h:panelGroup/>
            <h:outputText value="add author(s)"/><h:panelGroup/><h:panelGroup/>
            <h:outputLabel for="autId"><h:outputText value="author id"/></h:outputLabel>
            <h:inputText id="autId" value="#{bookAdd.aut}"><f:validateDoubleRange minimum="1"/></h:inputText>
            <h:commandLink actionListener="#{bookAdd.addAut}" value="add author"/>
            <h:outputText value="authors"/>
            <h:dataTable value="#{bookAdd.authors}" var="cr">
                <h:column>
                    <f:facet name="header"><h:outputText value="Id"/></f:facet>
                    <h:outputText value="#{cr.id}"/>
                    <f:facet name="footer"><h:outputText value="Id"/></f:facet>
                </h:column>
                <h:column>
                    <f:facet name="header"><h:outputText value="Name"/></f:facet>
                    <h:outputText value="#{cr.name}"/>
                    <f:facet name="footer"><h:outputText value="Name"/></f:facet>
                </h:column>
                <h:column>
                    <f:facet name="header"><h:outputText value="operation"/></f:facet>
                    <h:commandLink value="remove" actionListener="#{bookAdd.delAut}" title="#{cr.id}"/>
                    <f:facet name="footer"><h:outputText value=""/></f:facet>
                </h:column>
            </h:dataTable>
        </h:panelGrid>
    </h:form>
</f:subview>

and related managed bean (the problem specify with [x])

package BBeans;

import _PBeans.books;
import java.util.ArrayList;
import java.util.List;
import javax.annotation.Resource;
import javax.faces.application.FacesMessage;
import javax.faces.component.html.HtmlCommandLink;
import javax.faces.context.FacesContext;
import javax.faces.event.ActionEvent;
import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
import javax.persistence.PersistenceUnit;
import javax.transaction.UserTransaction;

public class bookAdd {
    
    private String name;
    private double price;
    private int aut;
    public int getAut(){return this.aut;}
    public void setAut(int aut){this.aut=aut;}
    private List<_PBeans.authors> authors=new ArrayList<_PBeans.authors>();
    public bookAdd(){}
    @PersistenceUnit(unitName="JPA")private EntityManagerFactory EMF;
    @Resource private UserTransaction JTA;
    public List<_PBeans.authors> getAuthors(){return this.authors;}
    public void setname(String name){this.name=name;}
    public String getName(){return this.name;}
    public void setPrice(double price){this.price=price;}
    public double getPrice(){return this.price;}
    public void addBook(ActionEvent act){
        boolean grant=FacesContext.getCurrentInstance().getApplication().createValueBinding("#{user.access}").getValue(FacesContext.getCurrentInstance()).equals(true);
    if(grant){EntityManager EM=EMF.createEntityManager();
    try{_PBeans.books book=new books();JTA.begin();
    book.setname(this.name);book.setPrice(this.price);book.SetAuthors(this.authors);
    EM.persist(book); //[0]
    JTA.commit();
    FacesContext.getCurrentInstance().addMessage(null, new FacesMessage("//new book added successfully")); //[x]
    this.price=0;this.name="";this.authors.clear();this.aut=0; //[1]
    }catch(Exception e){FacesContext.getCurrentInstance().addMessage(null, new FacesMessage("an error occured during adding operation "+e));}
    finally{EM.close();}
    }
    }
    public void addAut(ActionEvent act){
        for(int i=0;i<this.authors.size();i++){
            if(this.authors.get(i).getId()==this.aut){FacesContext.getCurrentInstance().addMessage(null, new FacesMessage("the author with "+this.aut+" id has been added"));return;}}
        EntityManager EM=EMF.createEntityManager();
    try{
    _PBeans.authors author=EM.find(_PBeans.authors.class, this.aut);
    if(author==null){FacesContext.getCurrentInstance().addMessage(null, new FacesMessage("Error: author with \""+this.aut+"\" id not exist"));}
    else{this.authors.add(author);}
    }catch(Exception e){FacesContext.getCurrentInstance().addMessage(null, new FacesMessage("an error occured during adding author "+e));}
    finally{EM.close();}
    }
    public void delAut(ActionEvent act){
    HtmlCommandLink id=(HtmlCommandLink)act.getSource();
    String idd=(String)id.getTitle();
    for(int i=0;i<this.authors.size();i++){if(this.authors.get(i).getId()==Integer.parseInt(idd)){this.authors.remove(i);break;}}
    }
}

everything works okay, except addBook() method, id doesn't add any new record with JPA, or throws any exception, also it works till [x]
[0]:record(s) can not add to DB
[1]:this operation doesn't work(process)
*without any new record(s) or changes in database
*web server doesn't throw any exception

please help!

[Tim Holloway]

My guess is that your transaction commit process isn't correct, but I don't do anything that's remotely like what you're doing.

First of all, I'm using DTO/Service classes to handle the persistence rather than attempting to jam everything into the backing bean.

Secondly, I use Spring to manage the DTO/Service instances. Spring can automatically provide the transaction management as well as the grunt work of cleaning up exceptions and stuff like that. And Spring and JSF play together quite well.

While I use more classes to get the work done, the individual classes are all simpler, since they only attempt to accomplish one thing, and they're enough like related classes in the same tier that it makes for easier maintenance and testing.

[Jason Marlyn]

wow, i solved it,
I just change my provider "OpenJPA" and use

EntityManagerFactory EMF=Persistence.createEntityManagerFactory("JPA", System.getProperties());

instead of

@PersistenceUnit(unitName="JPA") private EntityManagerFactory EMF;  

and it works Okay
also thank you Mr. Holloway, I'd like to see an example of your solution
thanks anyway