hello,
I'm a newbie, now i'm trying to implement a web service,

Environnement:
jboss 4.2
seam 2.0
EJB 3
jpa
eclipse
jbosstools

I followed this : http://docs.jboss.org/seam/2.1.0.GA/reference/en-US/html/webservices.html

I have two entities, a session class to do the work for the web service and a web service class,
all that in well configured seam project.

Job.java :


`package entity;

import java.io.Serializable;
import java.util.ArrayList;
import java.util.List;

import javax.persistence.CascadeType;
import javax.persistence.Entity;
import javax.persistence.FetchType;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.OneToMany;
import javax.persistence.Table;

import org.jboss.seam.annotations.AutoCreate;
import org.jboss.seam.annotations.Name;

import com.sun.xml.bind.CycleRecoverable;


@SuppressWarnings("serial") //i'm ignoring this warning cuz i don't know what it's for !
@Entity
@Table(name = "job")
@Name("job")
@AutoCreate
public class Job implements Serializable,CycleRecoverable{
        @Id
        @GeneratedValue(strategy = GenerationType.AUTO)
        private Integer id_job;

        private String label;

        @OneToMany(fetch = FetchType.LAZY,mappedBy = "job", cascade = CascadeType.ALL)
        private List<User> listUser = new ArrayList<User>();

       
        /*
         * @see com.sun.xml.bind.CycleRecoverable#onCycleDetected(com.sun.xml.bind.CycleRecoverable.Context)
         * this method is invoked when a cycle is detected , exactly while generating xml file to send
         * response to client
         */
       
        public Object onCycleDetected(Context arg0) {
                Job job = new Job();
                job = new Job(this);
                job.setListUser(null);
                return (Object) job;
        }
       
        /*
         * I intentionally don't initialize list in the constructor
         */

        //Constructor
        public Job(Integer id, String label) {
                this.id_job = id;
                this.label = label;
        }

       
        //Default constructor
        public Job() {
        }
       

        //Copy constructor
        public Job(Job job) {
                this.id_job = job.getId_job();
                this.label = job.getLabel();
        }
       
       
        //Getters and setters
        public Integer getId_job() {
                return id_job;
        }

        public void setId_job(Integer id) {
                this.id_job = id;
        }

        public String getLabel() {
                return label;
        }

        public void setLabel(String label) {
                this.label = label;
        }

        public List<User> getListUser() {
                return listUser;
        }

        public void setListUser(List<User> listUser) {
                this.listUser = listUser;
        }
}`



User.java :
`package entity;

import java.io.Serializable;

import javax.persistence.Entity;
import javax.persistence.FetchType;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.ManyToOne;
import javax.persistence.Table;

import org.jboss.seam.annotations.AutoCreate;
import org.jboss.seam.annotations.Name;

import com.sun.xml.bind.CycleRecoverable;


@SuppressWarnings("serial")
@Entity
@Table(name = "user")
@Name("user")
@AutoCreate
public class User implements Serializable,CycleRecoverable {
       
        @Id
        @GeneratedValue(strategy = GenerationType.AUTO)
        private Integer id;

        private String username;

        private String password;

        @ManyToOne(fetch = FetchType.LAZY)
        @JoinColumn(name = "id_job", nullable = true)
        private Job job;


       
        /*
         * Constructors
         * I intentionally don't copy Job in the Copy constructor cuz i'm using it
         * in onCycledetected to stop cycle
         */
        public User() {
        }
       
        public User(Integer id, String username, String password) {
                this.id = id;
                this.username = username;
                this.password = password;
        }
       
        public User(User user) {
                setId(user.id);
                setPassword(user.getPassword());
                setUsername(user.getUsername());
        }
       
        /*
         * (non-Javadoc)
         * @see *com.sun.xml.bind.CycleRecoverable#onCycleDetected(com.sun.xml.bind.CycleRecoverable.Context)
         */
        public Object onCycleDetected(Context arg0) {
                User user = new User(this);
                user.setJob(this.job);         
                user.getJob().setListUser(this.job.getListUser());
               
                for (User us : this.job.getListUser()){
                        us.setJob(null);
                }
                return user;
        }
       
       
        //Getters and setters
        public Job getJob() {
                return job;
        }

        public void setJob(Job job) {
                this.job = job;
        }


        public Integer getId() {
                return id;
        }

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

        public String getUsername() {
                return username;
        }

        public void setUsername(String username) {
                this.username = username;
        }

        public String getPassword() {
                return password;
        }

        public void setPassword(String password) {
                this.password = password;
        }

}
`


WebServiceSession.java:

`package org.domain.registration.session;

import javax.persistence.EntityManager;

import org.jboss.seam.ScopeType;
import org.jboss.seam.annotations.AutoCreate;
import org.jboss.seam.annotations.Begin;
import org.jboss.seam.annotations.In;
import org.jboss.seam.annotations.Name;
import org.jboss.seam.annotations.Scope;


import entity.User;

@Name("webservicesession")
@Scope(ScopeType.CONVERSATION)
@AutoCreate
public class WebServiceSession {
       
        @In EntityManager entityManager;
       
        /*
         * i enjoyed this exception for a couple of hours : could not initialize proxy - no Session
         * when i add @begin it works.
         * what i want to know is : how it works without @begin when i use JSF ?
         */
        @Begin
        public User getUser(){
                String query = "select u from User u  where u.id = :id";
                User user = (User) entityManager.createQuery(query).setParameter("id", 3).getSingleResult();
                return user;
        }
       
        /*
         * what's happen if there is no @End, when the session will be closed and who's going to close it
         */
}
`


ServiceWebTest.java :


`package webServices;

import javax.ejb.Stateless;
import javax.jws.WebMethod;
import javax.jws.WebService;

import org.domain.registration.session.WebServiceSession;
import org.jboss.seam.Component;
import org.jboss.wsf.spi.annotation.WebContext;

import entity.User;


@WebService(name = "gpao", serviceName = "gpaoService")
@WebContext(contextRoot = "gpaoContext")
@Stateless
public class ServiceWebTest {
       
        /*
         * Since i can't use injection here (i would love to know why and what's the difference),
         * i use Component.getInstance to get the session
         */
       
        private WebServiceSession webservicesession =
                (WebServiceSession) Component.getInstance("webservicesession");
       
        @WebMethod
        public User extraire(){
                return webservicesession.getUser();
        }
}
`


Everything works as i want but i don't really understand what's going on inside, fortunately when i tried more than
one client i'm obliged to go deeply inside the framework.
Two clients i use are (soapUI plugin for eclipse and anothe client running on netbeans).

I have used eclipse debugger trying to understand what's going on inside, unfortunately
i don't reach a minimal of an understanding level that allow me to continue.

My Questions :
1)every client has a session (conversation) ?
2)when client's thread will be killed ?
3)do the instance of the session class is shared between clients

even some links are welcome .

Best Regards,
walid