Hibernate: no se pudo inicializar el proxy: no hay sesión (a través de la cadena de referencia ...)
Nota: Antes de que alguien se queje de que esto es un duplicado, asegúrese de revisar el contenido sin juzgar por el título. También asegúrese de leer cuidadosamente su pregunta de referencia y la respuesta para ver si está duplicada. A partir de mi experiencia ahora, el problema en esta pregunta puede suceder en diferentes entornos. Por ejemplo, la respuesta para alguien que usa el siguiente código enjsp será diferente para alguien que useSpring será diferente y para alguien cuyo DB es pequeño yeager la carga está bien será diferente. Y no, mi situación no es ninguna de ellas.
Estoy escribiendo unREST api usandoHibernateyJersey. Por favor, eche un vistazo al siguiente código.
VerificationCodeJSONService.java - La clase de servicio JSON
@Path("/verificaion_code")
public class VerificationCodeJSONService {
@GET
@Path("/getAllVerificationCodes")
@Produces(MediaType.APPLICATION_JSON)
public List<VerificaionCode> getAllVerificationCodes() {
VerificationCodeService verificationCodeService=new VerificationCodeService();
List<VerificaionCode> list = verificationCodeService.getAllVerificationCodes();
return list;
}
}
VerificationCodeService.java - La capa de servicio
public class VerificationCodeService {
private static VerificationCodeDAOInterface verificationCodeDAOInterface;
public VerificationCodeService() {
verificationCodeDAOInterface = new VerificationCodeDAOImpl();
}
public List<VerificaionCode> getAllVerificationCodes() {
Session session = verificationCodeDAOInterface.openCurrentSession();
Transaction transaction = null;
List<VerificaionCode> verificaionCodes = new ArrayList<VerificaionCode>();
try {
transaction = verificationCodeDAOInterface.openTransaction(session);
verificaionCodes = verificationCodeDAOInterface.getAllVerificationCodes(session);
transaction.commit();
} catch (Exception ex) {
ex.printStackTrace();
} finally {
session.close();
}
return verificaionCodes;
}
}
VerificationCodeDAOImpl.java - La capa de base de datos
public class VerificationCodeDAOImpl implements VerificationCodeDAOInterface{
private static final SessionFactoryBuilder sessionFactoryBuilder = SessionFactoryBuilder.getInstance();
@Override
public List<VerificaionCode> getAllVerificationCodes(Session session) {
List<VerificaionCode> verificaionCodes=(List<VerificaionCode>)session.createQuery("from VerificaionCode").list();
return verificaionCodes;
}
}
VerificationCode.java - La capa DAO
public class VerificaionCode implements java.io.Serializable {
private Integer idverificaionCode;
private Patient patient;
private String code;
private Date dateCreated;
private Date lastUpdated;
public VerificaionCode() {
}
public VerificaionCode(Patient patient, String code, Date lastUpdated) {
this.patient = patient;
this.code = code;
this.lastUpdated = lastUpdated;
}
public VerificaionCode(Patient patient, String code, Date dateCreated, Date lastUpdated) {
this.patient = patient;
this.code = code;
this.dateCreated = dateCreated;
this.lastUpdated = lastUpdated;
}
public Integer getIdverificaionCode() {
return this.idverificaionCode;
}
public void setIdverificaionCode(Integer idverificaionCode) {
this.idverificaionCode = idverificaionCode;
}
public Patient getPatient() {
return this.patient;
}
public void setPatient(Patient patient) {
this.patient = patient;
}
public String getCode() {
return this.code;
}
public void setCode(String code) {
this.code = code;
}
public Date getDateCreated() {
return this.dateCreated;
}
public void setDateCreated(Date dateCreated) {
this.dateCreated = dateCreated;
}
public Date getLastUpdated() {
return this.lastUpdated;
}
public void setLastUpdated(Date lastUpdated) {
this.lastUpdated = lastUpdated;
}
}
Paciente.java - La capa DAO
public class Patient implements java.io.Serializable {
private Integer idpatient;
private DiabetesType diabetesType;
private Language language;
private String customId;
private String diabetesOther;
private String firstName;
private String lastName;
private String email;
private Date dob;
private String parentEmail;
private String gender;
private Date diagnosedDate;
private Double height;
private Double weight;
private String heightUnit;
private String weightUnit;
private String theme;
private String userName;
private String password;
private Date dateCreated;
private Date lastUpdated;
public Patient() {
}
public Patient(DiabetesType diabetesType, Language language, String customId, String firstName, String email, Date dob, String gender, String theme, String userName, String password, Date lastUpdated) {
this.diabetesType = diabetesType;
this.language = language;
this.customId = customId;
this.firstName = firstName;
this.email = email;
this.dob = dob;
this.gender = gender;
this.theme = theme;
this.userName = userName;
this.password = password;
this.lastUpdated = lastUpdated;
}
public Integer getIdpatient() {
return this.idpatient;
}
public void setIdpatient(Integer idpatient) {
this.idpatient = idpatient;
}
public DiabetesType getDiabetesType() {
return this.diabetesType;
}
public void setDiabetesType(DiabetesType diabetesType) {
this.diabetesType = diabetesType;
}
public Language getLanguage() {
return this.language;
}
public void setLanguage(Language language) {
this.language = language;
}
public String getCustomId() {
return this.customId;
}
public void setCustomId(String customId) {
this.customId = customId;
}
public String getDiabetesOther() {
return this.diabetesOther;
}
public void setDiabetesOther(String diabetesOther) {
this.diabetesOther = diabetesOther;
}
public String getFirstName() {
return this.firstName;
}
public void setFirstName(String firstName) {
this.firstName = firstName;
}
public String getLastName() {
return this.lastName;
}
public void setLastName(String lastName) {
this.lastName = lastName;
}
public String getEmail() {
return this.email;
}
public void setEmail(String email) {
this.email = email;
}
public Date getDob() {
return this.dob;
}
public void setDob(Date dob) {
this.dob = dob;
}
public String getParentEmail() {
return this.parentEmail;
}
public void setParentEmail(String parentEmail) {
this.parentEmail = parentEmail;
}
public String getGender() {
return this.gender;
}
public void setGender(String gender) {
this.gender = gender;
}
public Date getDiagnosedDate() {
return this.diagnosedDate;
}
public void setDiagnosedDate(Date diagnosedDate) {
this.diagnosedDate = diagnosedDate;
}
public Double getHeight() {
return this.height;
}
public void setHeight(Double height) {
this.height = height;
}
public Double getWeight() {
return this.weight;
}
public void setWeight(Double weight) {
this.weight = weight;
}
public String getHeightUnit() {
return this.heightUnit;
}
public void setHeightUnit(String heightUnit) {
this.heightUnit = heightUnit;
}
public String getWeightUnit() {
return this.weightUnit;
}
public void setWeightUnit(String weightUnit) {
this.weightUnit = weightUnit;
}
public String getTheme() {
return this.theme;
}
public void setTheme(String theme) {
this.theme = theme;
}
public String getUserName() {
return this.userName;
}
public void setUserName(String userName) {
this.userName = userName;
}
public String getPassword() {
return this.password;
}
public void setPassword(String password) {
this.password = password;
}
public Date getDateCreated() {
return this.dateCreated;
}
public void setDateCreated(Date dateCreated) {
this.dateCreated = dateCreated;
}
public Date getLastUpdated() {
return this.lastUpdated;
}
public void setLastUpdated(Date lastUpdated) {
this.lastUpdated = lastUpdated;
}
}
Abajo están misHibernate archivos de mapeo para los POJO anteriores
VerificaionCode.hbm.xml
<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd">
<!-- Generated Sep 23, 2016 3:21:00 PM by Hibernate Tools 4.3.1 -->
<hibernate-mapping>
<class name="beans.VerificaionCode" table="verificaion_code" catalog="myglukose" optimistic-lock="version">
<id name="idverificaionCode" type="java.lang.Integer">
<column name="idverificaion_code" />
<generator class="identity" />
</id>
<many-to-one name="patient" class="beans.Patient" fetch="select">
<column name="patient_idpatient" not-null="true" />
</many-to-one>
<property name="code" type="string">
<column name="code" length="45" not-null="true" />
</property>
<property name="dateCreated" type="timestamp">
<column name="date_created" length="19" />
</property>
<property name="lastUpdated" type="timestamp">
<column name="last_updated" length="19" not-null="true" />
</property>
</class>
</hibernate-mapping>
Paciente.hbm.xml
<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd">
<!-- Generated Sep 23, 2016 3:21:00 PM by Hibernate Tools 4.3.1 -->
<hibernate-mapping>
<class name="beans.Patient" table="patient" catalog="myglukose" optimistic-lock="version">
<id name="idpatient" type="java.lang.Integer">
<column name="idpatient" />
<generator class="identity" />
</id>
<many-to-one name="diabetesType" class="beans.DiabetesType" fetch="select">
<column name="diabetes_type_iddiabetes_type" not-null="true" />
</many-to-one>
<many-to-one name="language" class="beans.Language" fetch="select">
<column name="language_idlanguage" not-null="true" />
</many-to-one>
<property name="customId" type="string">
<column name="custom_id" length="45" not-null="true" />
</property>
<property name="diabetesOther" type="string">
<column name="diabetes_other" length="45" />
</property>
<property name="firstName" type="string">
<column name="first_name" length="100" not-null="true" />
</property>
<property name="lastName" type="string">
<column name="last_name" length="100" />
</property>
<property name="email" type="string">
<column name="email" length="45" not-null="true" />
</property>
<property name="dob" type="date">
<column name="dob" length="10" not-null="true" />
</property>
<property name="parentEmail" type="string">
<column name="parent_email" length="45" />
</property>
<property name="gender" type="string">
<column name="gender" length="45" not-null="true" />
</property>
<property name="diagnosedDate" type="date">
<column name="diagnosed_date" length="10" />
</property>
<property name="height" type="java.lang.Double">
<column name="height" precision="22" scale="0" />
</property>
<property name="weight" type="java.lang.Double">
<column name="weight" precision="22" scale="0" />
</property>
<property name="heightUnit" type="string">
<column name="height_unit" length="45" />
</property>
<property name="weightUnit" type="string">
<column name="weight_unit" length="45" />
</property>
<property name="theme" type="string">
<column name="theme" length="45" not-null="true" />
</property>
<property name="userName" type="string">
<column name="user_name" length="45" not-null="true" />
</property>
<property name="password" type="string">
<column name="password" length="45" not-null="true" />
</property>
<property name="dateCreated" type="timestamp">
<column name="date_created" length="19" />
</property>
<property name="lastUpdated" type="timestamp">
<column name="last_updated" length="19" not-null="true">
<comment>Stores the basic information of the patient</comment>
</column>
</property>
</class>
</hibernate-mapping>
Sin embargo, cuando ejecuto este código a través dehttp://localhost:8080/example_rest/rest/verificaion_code/getAllVerificationCodes Recibo el siguiente error.
could not initialize proxy - no Session (through reference chain: java.util.ArrayList[0]->beans.VerificaionCode["patient"]->beans.Patient_$_jvst40f_7["diabetesType"])
Como puedes verdiabetesType es unObject (Clave externa) en la mesa del paciente y no tiene nada que ver conVerificationCode. ¿Cómo puedo arreglar esto?
Tenga en cuenta que este es unREST API Por lo tanto, no puedo cargarlos en un JSP como en una aplicación web.
Actualizar
Como recomendó @Kayaman, realicé las actualizaciones haciendonull. Por favor, consulte el siguiente código. Me di cuenta queverificaionCodes.get(i).getPatient().set...(null) comete el mismo error que el anterior, así que intenté a continuación, que comenzó a funcionar bien.
VerificationCodeService.java
public List<VerificaionCode> getAllVerificationCodes() {
Session session = verificationCodeDAOInterface.openCurrentSession();
Transaction transaction = null;
List<VerificaionCode> verificaionCodes = new ArrayList<VerificaionCode>();
try {
transaction = verificationCodeDAOInterface.openTransaction(session);
verificaionCodes = verificationCodeDAOInterface.getAllVerificationCodes(session);
transaction.commit();
} catch (Exception ex) {
ex.printStackTrace();
} finally {
session.close();
for(int i=0;i<verificaionCodes.size();i++)
{
Patient p = new Patient();
System.out.println(verificaionCodes.get(i).getPatient().getIdpatient());
Integer idpatient = verificaionCodes.get(i).getPatient().getIdpatient();
p.setIdpatient(idpatient);
verificaionCodes.get(i).setPatient(p);
}
}
return verificaionCodes;
}