could not load an entity - JPA and Hibernate

[Timothy Sam]

Sorry for the title, I could not think of anything more descriptive about the problem I'm having right now. I was trying the netbeans 5.5 CRUD functionality with JPA and Hibernate. I'm getting the following errors below...

HTTP Status 500 -

--------------------------------------------------------------------------------

type Exception report

message

description The server encountered an internal error () that prevented it from fulfilling this request.

exception

javax.servlet.ServletException: #{userType.editSetup}: javax.faces.el.EvaluationException: javax.persistence.PersistenceException: org.hibernate.exception.GenericJDBCException: could not load an entity: [com.wp.wpinventory.db.UserType#2]
javax.faces.webapp.FacesServlet.service(FacesServlet.java:209)
org.netbeans.modules.web.monitor.server.MonitorFilter.doFilter(MonitorFilter.java:368)


root cause

javax.faces.FacesException: #{userType.editSetup}: javax.faces.el.EvaluationException: javax.persistence.PersistenceException: org.hibernate.exception.GenericJDBCException: could not load an entity: [com.wp.wpinventory.db.UserType#2]
com.sun.faces.application.ActionListenerImpl.processAction(ActionListenerImpl.java:78)
javax.faces.component.UICommand.broadcast(UICommand.java:312)
javax.faces.component.UIData.broadcast(UIData.java:657)
javax.faces.component.UIViewRoot.broadcastEvents(UIViewRoot.java:267)
javax.faces.component.UIViewRoot.processApplication(UIViewRoot.java:381)
com.sun.faces.lifecycle.InvokeApplicationPhase.execute(InvokeApplicationPhase.java:75)
com.sun.faces.lifecycle.LifecycleImpl.phase(LifecycleImpl.java:200)
com.sun.faces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:90)
javax.faces.webapp.FacesServlet.service(FacesServlet.java:197)
org.netbeans.modules.web.monitor.server.MonitorFilter.doFilter(MonitorFilter.java:368)


note The full stack trace of the root cause is available in the Apache Tomcat/5.5.17 logs.

I'm pretty new to Hibernate and a total dumb ass in JPA. I somehow managed to add a record though but I could no longer edit. Here is my persistent class

/*
 * UserType.java
 *
 * Created on April 30, 2007, 6:21 PM
 *
 * To change this template, choose Tools | Template Manager
 * and open the template in the editor.
 */
 
package com.wp.wpinventory.db;
 
import java.io.Serializable;
import java.util.Collection;
import javax.persistence.CascadeType;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.GenerationType;
import javax.persistence.GeneratedValue;
import javax.persistence.NamedQueries;
import javax.persistence.NamedQuery;
import javax.persistence.OneToMany;
import javax.persistence.Table;
 
/**
 * Entity class UserType
 * 
 * @author paul.timothy
 */
@Entity
@Table(name = "user_type")
@NamedQueries( {
@NamedQuery(name = "UserType.findByUserTypeId", query = "SELECT u FROM UserType u WHERE u.userTypeId = :userTypeId"),
@NamedQuery(name = "UserType.findByDescription", query = "SELECT u FROM UserType u WHERE u.description =  :mrgreen: escription")
})
public class UserType implements Serializable {
 
@Id
@GeneratedValue(strategy=GenerationType.AUTO)
@Column(name = "user_type_id", nullable = false)
private Integer userTypeId;
 
@Column(name = "description", nullable = false)
private String description;
 
@OneToMany(cascade = CascadeType.ALL, mappedBy = "userTypeId")
private Collection<User> userCollection;
    
    /** Creates a new instance of UserType */
    public UserType() {
    }
 
/**
 * Creates a new instance of UserType with the specified values.
 * @param userTypeId the userTypeId of the UserType
 */
public UserType(Integer userTypeId) {
this.userTypeId = userTypeId;
}
 
/**
 * Creates a new instance of UserType with the specified values.
 * @param userTypeId the userTypeId of the UserType
 * @param description the description of the UserType
 */
public UserType(Integer userTypeId, String description) {
this.userTypeId = userTypeId;
this.description = description;
}
 
/**
 * Gets the userTypeId of this UserType.
 * @return the userTypeId
 */
public Integer getUserTypeId() {
return this.userTypeId;
}
 
/**
 * Sets the userTypeId of this UserType to the specified value.
 * @param userTypeId the new userTypeId
 */
public void setUserTypeId(Integer userTypeId) {
this.userTypeId = userTypeId;
}
 
/**
 * Gets the description of this UserType.
 * @return the description
 */
public String getDescription() {
return this.description;
}
 
/**
 * Sets the description of this UserType to the specified value.
 * @param description the new description
 */
public void setDescription(String description) {
this.description = description;
}
 
/**
 * Gets the userCollection of this UserType.
 * @return the userCollection
 */
public Collection<User> getUserCollection() {
return this.userCollection;
}
 
/**
 * Sets the userCollection of this UserType to the specified value.
 * @param userCollection the new userCollection
 */
public void setUserCollection(Collection<User> userCollection) {
this.userCollection = userCollection;
}
 
/**
 * Returns a hash code value for the object.  This implementation computes 
 * a hash code value based on the id fields in this object.
 * @return a hash code value for this object.
 */
@Override
public int hashCode() {
int hash = 0;
hash += (this.userTypeId != null ? this.userTypeId.hashCode() : 0);
return hash;
}
 
/**
 * Determines whether another object is equal to this UserType.  The result is 
 * <code>true</code> if and only if the argument is not null and is a UserType object that 
 * has the same id field values as this object.
 * @param object the reference object with which to compare
 * @return <code>true</code> if this object is the same as the argument;
 * <code>false</code> otherwise.
 */
@Override
public boolean equals(Object object) {
// TODO: Warning - this method won't work in the case the id fields are not set
if (!(object instanceof UserType)) {
return false;
}
UserType other = (UserType)object;
if (this.userTypeId != other.userTypeId && (this.userTypeId == null || !this.userTypeId.equals(other.userTypeId))) return false;
return true;
}
 
/**
 * Returns a string representation of the object.  This implementation constructs 
 * that representation based on the id fields.
 * @return a string representation of the object.
 */
@Override
public String toString() {
return "com.wp.wpinventory.db.UserType[userTypeId=" + userTypeId + "]";
}
    
}
 

I hope you guys could help me. Thanks!