Hibernate-无法懒惰地初始化角色集合：beans.Language.patients，无法初始化代理 - 无Session [英] Hibernate- failed to lazily initialize a collection of role: beans.Language.patients, could not initialize proxy - no Session

问题描述

我使用hibernate创建一个rest api。我创建了一个方法来获取表中的所有项目。

  public List< Language> getAllLanguages（Session session）{
 List< Language>语言=（List< Language>）session.createQuery（from Language）。 
返回语言; 
 
 $ / code> 

这是我的Language.java

  public class语言实现java.io.Serializable {
 
 
 private Integer idlanguage; 
私有字符串语言; 
私人套餐< Patient>患者=新HashSet<患者>（0）; 
 $ b public语言（）{
} 
 
 
公共语言（字符串语言）{
 this.language = language; 
} 
 public Language（String language，Set< Patient> patients）{
 this.language = language; 
 this.patients =患者; 
} 
 
 public Integer getIdlanguage（）{
 return this.idlanguage; 
} 
 
 public void setIdlanguage（Integer idlanguage）{
 this.idlanguage = idlanguage; 
} 
 public String getLanguage（）{
 return this.language; 
} 
 
 public void setLanguage（String language）{
 this.language = language; 
} 
 public Set< Patient> getPatients（）{
 return this.patients; 
} 
 
 public void setPatients（Set< Patient> patients）{
 this.patients = patients; 
} 
 
} 
  

这是我的Patient.java

  //生成2016年9月14日4:33:23由Hibernate Tools 4.3.1 
 
 
导入beans.DiabetesType; 
 import beans.Illness; 
 import beans.Language; 
 import beans.Reminder; 
 import java.util.Date; 
 import java.util.HashSet; 
 import java.util.Set; 
 
 / ** 
 *由hbm2java生成的患者
 * / 
公共类Patient实现java.io.Serializable {
 
 private Integer idpatient; 
私人DiabetesType糖尿病类型; 
私人语言语言; 
 private String customId; 
私人字符串diabetesOther; 
 private String firstName; 
 private String lastName; 
 private String userName; 
私人字符串密码; 
私人日期dateCreated; 
私人日期lastUpdated; 
私人套餐<疾病>疾病=新的HashSet<疾病>（0）; 
私人套餐<提醒>提醒= new HashSet< Reminder>（0）; 
 
 $ b公共病人（）{
} 
 
公共病人（整数病人，字符串密码）{
 this.idpatient = idpatient; 
 this.password =密码; 
 
 $ b $公共患者（DiabetesType diabetesType，语言语言，字符串customId，字符串firstName，字符串userName，字符串密码，Date lastUpdated日期）{
 this.diabetesType = diabetesType; 
 this.language = language; 
 this.customId = customId; 
 this.firstName = firstName; 
 this.userName = userName; 
 this.password =密码; 
 this.lastUpdated = lastUpdated; 
} 
 public patient（DiabetesType diabetesType，Language language，String customId，String diabetesOther，String firstName，String lastName，String userName，String password，Date dateCreated，Date lastUpdated，Set< Illness> illnesses，Set<提醒>提醒）{
 this.diabetesType = diabetesType; 
 this.language = language; 
 this.customId = customId; 
 this.diabetesOther = diabetesOther; 
 this.firstName = firstName; 
 this.lastName = lastName; 
 this.userName = userName; 
 this.password =密码; 
 this.dateCreated = dateCreated; 
 this.lastUpdated = lastUpdated; 
 this.illnesses =疾病; 
 this.reminders =提醒; 
} 
 
 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语言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 diabetes Other）{
 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 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; 
} 
 public Set< Illness> getIllnesses（）{
返回this.illnesses; 
} 
 
 public void setIllnesses（Set  this.illnesses = illnesses; 
} 
 public Set< Reminder> getReminders（）{
返回this.reminders; 
} 
 
 public void setReminders（Set< Reminder> reminders）{
 this.reminders = reminders; 
 
 
 
 
 
 $ b 
 重要提示：bean和映射是相反的通过NetBeans从MySQL数据库设计。调用 getAllLangauges 时，我不需要获取任何与 patient 相关的数据。我的语言表只有2列， idlanguage 和语言 。  Patient 表格有一个foriegn键语言表  
 
 
 
在rest API中使用此方法之前，它完美无缺地运行。但是当我在休息api中使用它时，它在那里创造了一个复杂性。 
 
 
 
我没有在这里使用注释。我用hibernate反向工程向导来映射上面的实体。这是我的休息api方法。 
 
 
  @Path（/ language）
 public class LanguageJSONService {
 
 @GET 
 @Path（/ getAllLanguages）
 @Produces（MediaType.APPLICATION_JSON）
 public List< Language> getAllLanguages（）{
 LanguageService languageService = new LanguageService（）; 
列表<语言> list = languageService.getAllLanguages（）; 
返回列表; 
 
 
  
这就是我调用方法的方式， / p> 
 
 
 客户端客户端= ClientBuilder.newClient（）; 
列表<语言> list = client.target（http：// localhost：8080 / simple_rest / rest）
 .path（/ language / getAllLanguages）
 .request（MediaType.APPLICATION_JSON）
。 get（new GenericType< List< Language>>（）{
}）; 
 
 for（int i = 0; i< list.size（）; i ++）{
 System.out.println（Id  - + list.get（i）.getIdlanguage （）+Language  - + list.get（i）.getLanguage（））; 
} 
  
当我调用该方法时，
 
 
 未能延迟初始化一个角色集合：beans.Language.patients，无法初始化代理 - 没有会话（通过引用链：java.util.ArrayList [0]  - > beans.Language [patients]）
  
发生。 
 
 
有趣的是，如果我没有关闭会话，那么我会得到如下的输出，这完全是别的，好像它试图显示它的外键表和它们的外键表等等... 
  [{idlanguage：1，language：English，patients：
 [{idpatient：1，diabetesType：{iddiabetesType：1，type：Sever，patients：
 [{idpatient：1，diabetesType iddiabetesType：1，type：Sever，patients：
 [{idpatient：1，diabetesType：{iddiabetesType：1，type ：
 [{idpatient：1，diabetesType：{iddiabetesType：1，type：Sever，patients：
 [{idpatient diabetesType：{iddiabetesType：1，type：Sever，patients：
 [{idpatient：1，diabetesType：{iddiabetesType：1，type 患者：
 [{idpatient：1，diabetesType：{iddiabetesType：1，type：Sever，patients：
 [{ idpatient：1，diabetesType：{iddiabetesType：1，type：Sever，patients：
 [{idpatient：1，diabetesType：{iddiabetesType ，type：Sever，patients：[{idpatient：1，diabetesType：{iddiabetesType：1，type：Sever， idpatient：1，diabetesType：{iddiabetesType：1，type：Sever，patients：
 [{idpatient：1，diabetesType：{iddiabetesType 1，type：Sever，patients：
 [{idpatient：1，diabetesType：{iddiabetesType：1，type：Sever，patients b $ b [{idpatient：1，diabetesType：
  
对这个问题有什么想法？  
 
 
 更新  
 
 
我的配置文件 
 
  hibernate.cfg.xml  
 
 
 <？xml version =1.0encoding =UTF-8 >？; 
<！DOCTYPE hibernate-configuration PUBLIC -  // Hibernate / Hibernate Configuration DTD 3.0 // ENhttp://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd\"> 
< hibernate-configuration> 
< session-factory> 
< property name =show_sql> true< / property> 
< property name =hibernate.dialect> org.hibernate.dialect.MySQLDialect< / property> 
< property name =hibernate.connection.driver_class> com.mysql.jdbc.Driver< / property> 
< property name =hibernate.connection.url> jdbc：mysql：// localhost：3306 / *****< / property> 
< property name =hibernate.connection.username> *****< / property> 
< property name =hibernate.c3p0.min_size> 5< / property> 
< property name =hibernate.c3p0.max_size> 20< / property> 
< property name =hibernate.c3p0.timeout> 3000< / property> 
< property name =hibernate.c3p0.max_statements> 50< / property> 
< property name =hibernate.c3p0.idle_test_period> 300< / property> 
< property name =hibernate.c3p0.testConnectionOnCheckout> true< / property> 
< property name =hibernate.c3p0.preferredTestQuery> SELECT 1< / property> 
< property name =hibernate.connection.password> ************< / property> 
< mapping resource =beans / Reminder.hbm.xml/> 
< mapping resource =beans / Food.hbm.xml/> 
< mapping resource =beans / Patient.hbm.xml/> 
< mapping resource =beans / Illness.hbm.xml/> 
< mapping resource =beans / Language.hbm.xml/> 
< / session-factory> 
< / hibernate-configuration> 
  
 Language.hbm.xml 
 <？xml version =1.0？> 
<！DOCTYPE hibernate-mapping PUBLIC -  // Hibernate / Hibernate映射DTD 3.0 // EN
http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd > 
<！ - 由Hibernate Tools 4.3.1  - >生成的2016年9月14日4:33:23 PM 
< hibernate-mapping> 
< class name =beans.Languagetable =languagecatalog =myglukoseoptimistic-lock =version> 
< id name =idlanguagetype =java.lang.Integer> 
< column name =idlanguage/> 
< generator class =identity/> 
< / id> 
< property name =languagetype =string> 
< column name =languagelength =45not-null =true/> 
< / property> 
< set name =patientstable =patientinverse =truelazy =truefetch =select> 
< key> 
< column name =language_idlanguagenot-null =true/> 
< / key> 
 < / set> 
< / class> 
< / hibernate-mapping> 
  
这是我的患者映射文件， 
 
 
 Patient.hbm.xml  
 
 
 <？xml version =1.0？> 
<！DOCTYPE hibernate-mapping PUBLIC -  // Hibernate / Hibernate映射DTD 3.0 // EN
http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd > 
<！ - 由Hibernate Tools 4.3.1  - >生成的2016年9月14日4:33:23 PM 
< hibernate-mapping> 
< class name =beans.Patienttable =patientcatalog =myglukoseoptimistic-lock =version> 
< id name =idpatienttype =java.lang.Integer> 
< column name =idpatient/> 
< generator class =identity/> 
< / id> 
 < column name =diabetes_type_iddiabetes_typenot-null =true/> 
< /多对一> 
 < column name =language_idlanguagenot-null =true/> 
< /多对一> 
< property name =customIdtype =string> 
< column name =custom_idlength =45not-null =true/> 
< / property> 
< property name =diabetesOthertype =string> 
< column name =diabetes_otherlength =45/> 
< / property> 
< property name =firstNametype =string> 
< column name =first_namelength =100not-null =true/> 
< / property> 
< property name =lastNametype =string> 
< column name =last_namelength =100/> 
< / property> 
< property name =userNametype =string> 
< column name =user_namelength =45not-null =true/> 
< / property> 
< property name =passwordtype =string> 
< column name =passwordlength =45not-null =true/> 
< / property> 
< property name =dateCreatedtype =timestamp> 
< column name =date_createdlength =19/> 
< / property> 
< property name =lastUpdatedtype =timestamp> 
< column name =last_updatedlength =19not-null =true> 
< comment>存储患者的基本信息< / comment> 
< / column> 
< / property> 
< set name =illnessestable =illnessinverse =truelazy =truefetch =select> 
< key> 
< column name =patient_idpatientnot-null =true/> 
< / key> 
<一对多课程=beans.Illness/> 
< / set> 
< set name =reminderstable =reminderinverse =truelazy =truefetch =select> 
< key> 
< column name =patient_idpatientnot-null =true/> 
< / key> 
<一对多课程=beans.Reminder/> 
< / set> 
< / class> 
< / hibernate-mapping> 
  
 
 
解决方案
你的json转换器试图序列化整个实体，包含说每种语言的所有患者的列表。根据我的理解，json中的患者列表并不是预期的。所以你有三个选项（我会考虑它们的顺序）：
 
 
 
 
删除语言实体中患者的映射。你需要从语言实体的患者那里获得
 s吗？如果不删除此映射。
 
 
创建一个语言DTO，您可以在退出tx图层之前传输数据。这种方式调用服务的人永远不会得到LazyInitException。毫不奇怪：DTO字段总是急切地设置。
 
 
配置你的json转换器不要序列化病人字段。你还没有说你正在使用哪个json库。其中一些为您提供注释以忽略某些字段（例如，针对Jackson的 @JsonIgnore ），其他则需要Java配置。
 
 
 
 
 
要应用第一个解决方案，请以这种方式更新这些文件： 
 
 
 Language.hbm.xml  
 
 
 <？xml version =1.0？> 
<！DOCTYPE hibernate-mapping PUBLIC -  // Hibernate / Hibernate映射DTD 3.0 // EN
http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd > 
<！ - 由Hibernate Tools 4.3.1  - >生成的2016年9月14日4:33:23 PM 
< hibernate-mapping> 
< class name =beans.Languagetable =languagecatalog =myglukoseoptimistic-lock =version> 
< id name =idlanguagetype =java.lang.Integer> 
< column name =idlanguage/> 
< generator class =identity/> 
< / id> 
< property name =languagetype =string> 
< column name =languagelength =45not-null =true/> 
< / property> 
< / class> 
< / hibernate-mapping> 
  
 Language.java  
 
  public class语言实现java.io.Serializable {
 private Integer idlanguage; 
私有字符串语言; 
 $ b保护语言（）{
} 
 
 
公共语言（字符串语言）{
 this.language = language; 
} 
 
 public Integer getIdlanguage（）{
 return this.idlanguage; 
} 
 
保护无效setIdlanguage（整数idlanguage）{
 this.idlanguage = idlanguage; 
} 
 public String getLanguage（）{
 return this.language; 
} 
 
 public void setLanguage（String language）{
 this.language = language; 
} 
} 
  
我更新了无参数构造函数， code> setId 方法为 protected 。您甚至可以将它们更新为 private ：只有hibernate应该使用它们（并且可以使用私有字段/方法）。
 
I use hibernate to create a rest api. I create a method to get all items in a table.
public List<Language> getAllLanguages(Session session) {
        List<Language> languages=(List<Language>)session.createQuery("from Language").list();
        return languages;
}
This is my Language.java
public class Language  implements java.io.Serializable {


     private Integer idlanguage;
     private String language;
     private Set<Patient> patients = new HashSet<Patient>(0);

    public Language() {
    }


    public Language(String language) {
        this.language = language;
    }
    public Language(String language, Set<Patient> patients) {
       this.language = language;
       this.patients = patients;
    }

    public Integer getIdlanguage() {
        return this.idlanguage;
    }

    public void setIdlanguage(Integer idlanguage) {
        this.idlanguage = idlanguage;
    }
    public String getLanguage() {
        return this.language;
    }

    public void setLanguage(String language) {
        this.language = language;
    }
    public Set<Patient> getPatients() {
        return this.patients;
    }

    public void setPatients(Set<Patient> patients) {
        this.patients = patients;
    }

}
And this is my Patient.java
// Generated Sep 14, 2016 4:33:23 PM by Hibernate Tools 4.3.1


import beans.DiabetesType;
import beans.Illness;
import beans.Language;
import beans.Reminder;
import java.util.Date;
import java.util.HashSet;
import java.util.Set;

/**
 * Patient generated by hbm2java
 */
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 userName;
     private String password;
     private Date dateCreated;
     private Date lastUpdated;
     private Set<Illness> illnesses = new HashSet<Illness>(0);
     private Set<Reminder> reminders = new HashSet<Reminder>(0);


    public Patient() {
    }

    public Patient(Integer idpatient, String password) {
        this.idpatient = idpatient;
        this.password = password;
    }    

    public Patient(DiabetesType diabetesType, Language language, String customId, String firstName, String userName, String password, Date lastUpdated) {
        this.diabetesType = diabetesType;
        this.language = language;
        this.customId = customId;
        this.firstName = firstName;
        this.userName = userName;
        this.password = password;
        this.lastUpdated = lastUpdated;
    }
    public Patient(DiabetesType diabetesType, Language language, String customId, String diabetesOther, String firstName, String lastName,  String userName, String password, Date dateCreated, Date lastUpdated, Set<Illness> illnesses, Set<Reminder> reminders) {
       this.diabetesType = diabetesType;
       this.language = language;
       this.customId = customId;
       this.diabetesOther = diabetesOther;
       this.firstName = firstName;
       this.lastName = lastName;      
       this.userName = userName;
       this.password = password;
       this.dateCreated = dateCreated;
       this.lastUpdated = lastUpdated;
       this.illnesses = illnesses;
       this.reminders = reminders;
    }

    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 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;
    }
    public Set<Illness> getIllnesses() {
        return this.illnesses;
    }

    public void setIllnesses(Set<Illness> illnesses) {
        this.illnesses = illnesses;
    }
    public Set<Reminder> getReminders() {
        return this.reminders;
    }

    public void setReminders(Set<Reminder> reminders) {
        this.reminders = reminders;
    }
}
Important: The beans and mappings are reverse engineered from MySQL database, via NetBeans. I do not need to get any data related to patient when calling getAllLangauges. My language table has only 2 columns, idlanguage and language. Patient table has a foriegn key of language table

Before using this method in rest api , it worked perfectly without any exception. But when I used this in rest api, it created a complexity in there. 

I am not using annotations in here. I used hibernate reverse engineering wizard to map above entities . This is my rest api method.
@Path("/language")
public class LanguageJSONService {

    @GET
    @Path("/getAllLanguages")
    @Produces(MediaType.APPLICATION_JSON)
    public List<Language> getAllLanguages(){
        LanguageService languageService=new LanguageService();
        List<Language> list = languageService.getAllLanguages();
        return list;
    }
}
This is the way how I call the method,
Client client = ClientBuilder.newClient();
List<Language> list = client.target("http://localhost:8080/simple_rest/rest")
                .path("/language/getAllLanguages")
                .request(MediaType.APPLICATION_JSON)
                .get(new GenericType<List<Language>>() {
                });

for (int i = 0; i < list.size(); i++) {
      System.out.println("Id - " + list.get(i).getIdlanguage() + " Language - " + list.get(i).getLanguage());
}
When I call the method ,
failed to lazily initialize a collection of role: beans.Language.patients, could not initialize proxy - no Session (through reference chain: java.util.ArrayList[0]->beans.Language["patients"])
is occurred.

Interestingly, if I did not close the session, then I get an output like below which is totally something else, seems like it is trying to display its foreign key tables and their foreign key tables and so on...
    [{"idlanguage":1,"language":"English","patients":
[{"idpatient":1,"diabetesType":{"iddiabetesType":1,"type":"Sever","patients":
[{"idpatient":1,"diabetesType":{"iddiabetesType":1,"type":"Sever","patients":
[{"idpatient":1,"diabetesType":{"iddiabetesType":1,"type":"Sever","patients":
[{"idpatient":1,"diabetesType":{"iddiabetesType":1,"type":"Sever","patients":
[{"idpatient":1,"diabetesType":{"iddiabetesType":1,"type":"Sever","patients":
[{"idpatient":1,"diabetesType":{"iddiabetesType":1,"type":"Sever","patients":
[{"idpatient":1,"diabetesType":{"iddiabetesType":1,"type":"Sever","patients":
[{"idpatient":1,"diabetesType":{"iddiabetesType":1,"type":"Sever","patients":
[{"idpatient":1,"diabetesType":{"iddiabetesType":1,"type":"Sever","patients":[{"idpatient":1,"diabetesType":{"iddiabetesType":1,"type":"Sever","patients":
[{"idpatient":1,"diabetesType":{"iddiabetesType":1,"type":"Sever","patients":
[{"idpatient":1,"diabetesType":{"iddiabetesType":1,"type":"Sever","patients":
[{"idpatient":1,"diabetesType":{"iddiabetesType":1,"type":"Sever","patients":
[{"idpatient":1,"diabetesType":
Have any ideas about this problem ? 

Update

my configuration file 

hibernate.cfg.xml
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-configuration PUBLIC "-//Hibernate/Hibernate Configuration DTD 3.0//EN" "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
  <session-factory>
    <property name="show_sql">true</property>
    <property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property>
    <property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>
    <property name="hibernate.connection.url">jdbc:mysql://localhost:3306/*****</property>
    <property name="hibernate.connection.username">*****</property>
    <property name="hibernate.c3p0.min_size">5</property>
    <property name="hibernate.c3p0.max_size">20</property>
    <property name="hibernate.c3p0.timeout">3000</property>
    <property name="hibernate.c3p0.max_statements">50</property>
    <property name="hibernate.c3p0.idle_test_period">300</property>
    <property name="hibernate.c3p0.testConnectionOnCheckout">true</property>
    <property name="hibernate.c3p0.preferredTestQuery">SELECT 1</property>
    <property name="hibernate.connection.password">************</property>
    <mapping resource="beans/Reminder.hbm.xml"/>
    <mapping resource="beans/Food.hbm.xml"/>
    <mapping resource="beans/Patient.hbm.xml"/>
    <mapping resource="beans/Illness.hbm.xml"/>
    <mapping resource="beans/Language.hbm.xml"/>
  </session-factory>
</hibernate-configuration>
Language.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 14, 2016 4:33:23 PM by Hibernate Tools 4.3.1 -->
<hibernate-mapping>
    <class name="beans.Language" table="language" catalog="myglukose" optimistic-lock="version">
        <id name="idlanguage" type="java.lang.Integer">
            <column name="idlanguage" />
            <generator class="identity" />
        </id>
        <property name="language" type="string">
            <column name="language" length="45" not-null="true" />
        </property>
        <set name="patients" table="patient" inverse="true" lazy="true" fetch="select">
            <key>
                <column name="language_idlanguage" not-null="true" />
            </key>
            <one-to-many class="beans.Patient" />
        </set>
    </class>
</hibernate-mapping>
This is my patient mapping file,

Patient.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 14, 2016 4:33:23 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="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>
        <set name="illnesses" table="illness" inverse="true" lazy="true" fetch="select">
            <key>
                <column name="patient_idpatient" not-null="true" />
            </key>
            <one-to-many class="beans.Illness" />
        </set>
        <set name="reminders" table="reminder" inverse="true" lazy="true" fetch="select">
            <key>
                <column name="patient_idpatient" not-null="true" />
            </key>
            <one-to-many class="beans.Reminder" />
        </set>
    </class>
</hibernate-mapping>

解决方案
Your json converter tries to serialize the whole entity, which contains the list of all patients speaking each language. From what i understood, the list of patient in the json is not expected. So you have three options (ordered in which i would consider them) :


Remove the mapping to patients in Language entity. Do you need to get acces
s to patients from the language entity ? If not remove this mapping.
Create a Language DTO where you transfer your data before exiting the tx layer. This way whoever calls the service will never get a LazyInitException. No surprise : DTO fields are always set eagerly.
Configure your json converter to not serialize the patient fields. You've not said which json lib you're using. Some of them give you an annotation to ignore some fields (@JsonIgnore for Jackson for example), other requires java configuration.


To apply the first solution, update those files this way :

Language.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 14, 2016 4:33:23 PM by Hibernate Tools 4.3.1 -->
<hibernate-mapping>
    <class name="beans.Language" table="language" catalog="myglukose" optimistic-lock="version">
        <id name="idlanguage" type="java.lang.Integer">
            <column name="idlanguage" />
            <generator class="identity" />
        </id>
        <property name="language" type="string">
            <column name="language" length="45" not-null="true" />
        </property>
    </class>
</hibernate-mapping>
Language.java
public class Language  implements java.io.Serializable {
    private Integer idlanguage;
    private String language;

    protected Language() {
    }


    public Language(String language) {
        this.language = language;
    }

    public Integer getIdlanguage() {
        return this.idlanguage;
    }

    protected void setIdlanguage(Integer idlanguage) {
        this.idlanguage = idlanguage;
    }
    public String getLanguage() {
        return this.language;
    }

    public void setLanguage(String language) {
        this.language = language;
    }
}
I've updated the no-arg constructor and setId method to protected. You can even update them to private : only hibernate should ever use them (and it can use private fields / methods).

                        
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