Hi,
I'm trying to upgrade my application from OpenJPA implementation 1.0.1 which was using JPA 1.0 to Hibernate 5.1.2
I'm getting nullpointer exception when trying to to call geResultList on a Entity class.
My Sample classes are below: (I've changed the class names as I can not share my original source code. But the mapping are same.)
1) Class Charger (Representing a sort of mobile charger that has 2 Pin)
{code}
@Entity
@Table(name = "Charger")
public class Charger ChargerEntityExt5 extends ChargerEntityAbstract ChargerEntity1Abstract implements Serializable {
@ Transient
private static final long serialVersionUID = -1L;
@ OneToMany(mappedBy=" charger chargerEntityExt5 ",targetEntity= PinEntityExt2 PortEntityExt5 .class,
fetch=FetchType.EAGER)
@Fetch(value = FetchMode.SUBSELECT)
public List< PinEntityExt2 PinEntityExt5 > pinEntityExtList;
public List< PinEntityExt2 PinEntityExt5 > getPinEntityExtList() {
return pinEntityExtList;
}
public void setPinEntityExtList(List< PinEntityExt2 PinEntityExt5 > pinEntityExtList) {
this.pinEntityExtList = pinEntityExtList;
}
}
{code}
2)
{code}
@MappedSuperclass
public class ChargerEntityAbstract ChargerEntity1Abstract implements Serializable {
private static final long serialVersionUID = 1L;
@Id
@Column(name="ID")
private public Long Id;
@Column(name="CHARGER_ID" , nullable = true )
private public String chargerId;
// *** Constructor ****
public ChargerEntityAbstract ChargerEntity1Abstract () {
}
// *** Getter and Setters *** @Override
public String toString() {
return "ChargerEntity [cpeId=" + Id!=null? Id.toString():"" +
", chargerId=" + chargerId!=null? chargerId.toString():"" + "]";
}
public Long getId() {
return this. Id;
}
public void setId(Long Id id ) {
this. Id = Id id ;
}
public String getChargerId() {
return chargerId;
}
public void setChargerId(String chargerId) {
this.chargerId = chargerId;
}
}
{code}
3) every charger has 2 pins so I've declared a bi-directional one to many mapping between Charger and pin.
{code}
@Entity
@Table(name = "PIN")
public class PinEntityExt2 PinEntityExt5 extends PinEntityAbstract PinEntity1Abstract implements Serializable{
@Transient
private static final long serialVersionUID = -1L;
@ManyToOne(optional=false)
@NotFound(action = NotFoundAction.IGNORE)
@JoinColumn(name="CHARGER_ID", referencedColumnName="CHARGER_ID", insertable= false, updatable = false)
private Charger charger ChargerEntityExt5 chargerEntityExt5 ;
public Charger getCharger ChargerEntityExt5 getChargerEntityExt5 () {
return this.charger chargerEntityExt5 ;
}
public void setCharger setChargerEntityExt5 ( Charger charger ChargerEntityExt5 chargerEntityExt5 ) {
this. charger chargerEntityExt5 = charger chargerEntityExt5 ;
}
}
{code}
4) PIN Entity has 2 properties. CHARGER_ID and PIN_NUMBER. this 2 field defines one record in the PIN table uniquely. So I've declared a IDclass (ChargerPin) for representing the composite key
{code}
@MappedSuperclass
@IdClass(ChargerPin.class)
public class PinEntityAbstract PinEntity1Abstract implements Serializable{
@Transient
private static final long serialVersionUID = 1L;
@Id
@Column(name="CHARGER_ID", nullable = true)
private public String chargerId;
@Id
@Column(name="PIN_NUMBER", nullable = true)
private public Long pinNumber pin ;
public PinEntity1Abstract() {
}
@Override
public String toString() {
return "PinEntity [chargerId=" + chargerId +
", port=" + pin!=null? pin.toString():"" + "]";
}
public String getChargerId() {
return chargerId;
}
public void setChargerId(String chargerId) {
this.chargerId = chargerId;
}
public Long getPinNumber getPin () {
return pinNumber pin ;
}
public void setPinNumber setPin (Long pinNumber pin ) {
this. pinNumber pin = pinNumber pin ;
}
}
{code}
{code}
public class ChargerPin implements java.io.Serializable{
@Transient
private static final long serialVersionUID = 1L;
private String chargerId;
private Long pinNumber pin ;
// **** Constructor *****
public ChargerPin() {
}
public ChargerPin(String chargerId kapId , Long pinNumber port ) {
this.chargerId = chargerId kapId ;
this. pinNumber pin = pinNumber port ;
}
@Override
public String getChargerId toString () {
return "kapId [ chargerId ;
}
public void setChargerId(String =" + chargerId ) {
this.chargerId ! = null? chargerId ;
}
public Long getPinNumber .toString () { :"" +
return pinNumber;
}
public void setPinNumber ", port=" + pin!=null? pin.toString ( Long pinNumber ) {
this.pinNumber = pinNumber :"" + "]" ;
}
@Override
public int hashCode() {
final int prime = 31;
int result = 1;
int chargerId kap = chargerId != null ?(Integer.parseInt(chargerId)):0;
int pinNumber kap_port = pinNumber pin !=null?( pinNumber pin ).intValue():0;
result = prime * result + chargerId kap ;
result = prime * result + pinNumber kap_port ;
return result;
}
@Override
public boolean equals(Object obj) {
//return ((o instanceof CpePort) && (kapId.equalsIgnoreCase(((CpePort) o).getKapId())) && (port == (((CpePort) o).getPort())));
if (this == obj)
return true;
if (obj == null)
return false;
if (!(obj instanceof ChargerPin CpePort1 ))
return false;
ChargerPin other = (ChargerPin) obj;
if (chargerId == null) {
if (other.chargerId != null)
return false;
} else if ( (other.chargerId ! = null) && chargerId.equals(other.chargerId)) {
return false;
}
if ( pinNumber pin == null) {
if (other. pinNumber pin != null)
return false;
} else if ( pinNumber (other.pin != null) && (pin != other. pinNumber pin ) )
return false;
return true;
}
public String getChargerId() {
return chargerId;
}
public void setChargerId(String chargerId) {
this.chargerId = chargerId;
}
public Long getPin() {
return pin;
}
public void setPin(Long pin) {
this.pin = pin;
}
}
{code}
5) Now while I'm invoking the below query I'm getting a nullPointer exception with Empty satck trace.
{code}
public class HibernateTestClass {
/**
* @param args
*/
public static EntityManagerFactory entityManagerFactory;
public static void main(String[] args) {
// TODO Auto-generated method stub
EntityManager em = null;
List< Charger ChargerEntityExt5 > ChargerList = null;
Query query = null;
String queryString = "SELECT ce FROM Charger ChargerEntityExt5 ce WHERE ce.chargerId=?1 ";
try {
try {
em = getChargerEntityManager createEntityManager ();
} catch (Exception e) {
System.out.println(e);
}
query = em.createQuery(queryString);
query.setParameter(1, "110284026");
ChargerList = query.getResultList();
System.out.println(ChargerList.size());
} catch (IllegalStateException e) {
log System . error out.println (e);
} catch (IllegalArgumentException e) {
log System . error out.println (e);
} catch (Exception e) {
log System . error out.println (e);
} finally{
closeEntityManager( em .close( );
}
}
public static EntityManager createEntityManager() {
entityManagerFactory = Persistence.createEntityManagerFactory("polcaincapu");
return entityManagerFactory.createEntityManager();
}
}
{ code}
Can you please help me here look into this bug . IS there anything wrong with the COMPOSITE Key implementation.
Earlier I was trying with Hibernate 5.1.1. version and then the code was throwing error as "Error accessing field by reflection for persistent property".
Then I changed the code base to use Hibernate version 5.1.2 and then without change of source code the exception got changed into Nullpointer exception. |
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