JPA problem need help on JoinColumn, OneToMany, and ManyToOne annotations

Question

I made a mistake in placing a foreign key.
but I don't really get what wrong with it
I have followed what shown on the book
Could somebody help me out? thanks!
package com.h2o;
import javax.persistence.*;
import java.util.*;
@Entity
@IdClass(h2oUserId.class)
@NamedQuery(name="findAllUsers", query="SELECT h FROM h2oUser h")
public class h2oUser {
     @Id @GeneratedValue(strategy=GenerationType.SEQUENCE) @Column(name="H2O_ID")
     private Long id;
     @Id
     @Column ( nullable = false)
     private String email;
     @Column ( nullable = false)
     private String nickName;
     @Column ( nullable = false)
     private String password;
     private String basePath;
     private String avatorPath;
     private boolean activated;
     @Temporal(TemporalType.DATE)
     private Date createDate;
     @Transient
     private static final String LARGE = "original";
     @Transient
     private static final String SMALL = "thumbernail";
     @OneToMany(mappedBy="h2oUser")
     private Collection<ImageBase> images;
        //getters and setters
package com.h2o;
import javax.persistence.*;
@Entity
public class ImageBase {
     @Id @GeneratedValue(strategy=GenerationType.SEQUENCE)
     private Long id;
     @Column(unique=true)
     private String imgFile;
     @Column(nullable=true)
     private String imgOriginalFile;
     @ManyToOne
     @JoinColumn
     private h2oUser user;
        //getters and setters
Caused by: org.hibernate.MappingException: Could not determine type for: com.h2o.h2oUser, at table: ImageBase, for columns: [org.hibernate.mapping.Column(user)]
     at org.hibernate.mapping.SimpleValue.getType(SimpleValue.java:304)
     at org.hibernate.mapping.SimpleValue.isValid(SimpleValue.java:288)
     at org.hibernate.mapping.Property.isValid(Property.java:216)
     at org.hibernate.mapping.PersistentClass.validate(PersistentClass.java:467)
     at org.hibernate.mapping.RootClass.validate(RootClass.java:268)
     at org.hibernate.cfg.Configuration.validate(Configuration.java:1287)
     at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1729)
     at org.hibernate.ejb.EntityManagerFactoryImpl.<init>(EntityManagerFactoryImpl.java:84)
     at org.hibernate.ejb.Ejb3Configuration.buildEntityManagerFactory(Ejb3Configuration.java:904)
     ... 9 more

Answer 1

Your solution may be there:
http://www.insideria.com/2010/02/using-coldfusion-9-orm-in-flex.html
Check out what Pedro did in the Flex class:
Note the tag:
[Entity]
[Id]
[ManyToOne
...etc...
package com.pcsilva.insideria.one.mxml.entity
[Bindable]
// pointing to an entity in ColdFusion
[RemoteClass(alias='com.pcsilva.insideria.one.cfml.entity.User')]
// declare entity
[Entity]
public class User
[Id] //statement identifier
public var id:Number = 0; // NaN is not going to ColdFusion
public var name:String;
public var lastname:String;
public var email:String;
// statement of relationship
[ManyToOne(targetEntity="com.pcsilva.insideria.one.cfml.entity.Group", fetchType="EAGER", cascadeType='ALL')]
[JoinColumn(name="group_id", referencedColumnName="id")]
// start property for use in getter groupname
public var group:Group = new Group();
[Transient] //add property read-only, which is not reflected in ColdFusion
public function get fullname():String
return name+' '+lastname;
[Transient] //add property read-only,  simplifies access the property
public function get groupname():String
return group.name;