Hibernate get entity by id

Question

I have user entity and trying to get it from base by id  The entity definition is below   package com hibernate logic   import java io Serializable  import java util Random   import javax persistence      Entity  Table name  users   public class User implements Serializable       private static final long serialVersionUID   1L    Id  Column name  user id   private Long userId    Column name  middlename   private String middlename    Column name  name   private String name    Column name  surname   private String surname    Column name  pass   private String pass     bi-directional many-to-one association to Role  ManyToOne  JoinColumn name  role id   private Role role   public User         Random random   new Random        this userId   random nextLong        this name           this surname           this middlename          public Long getUserId         return this userId     public void setUserId Long userId        this userId   userId     public String getMiddlename         return this middlename     public void setMiddlename String middlename        this middlename   middlename     public String getName         return this name     public void setName String name        this name   name     public String getSurname         return this surname     public void setSurname String surname        this surname   surname     public Role getRole         return this role     public void setRole Role role        this role   role     public String getPass         return pass     public void setPass String pass        this pass   pass         So the method getUserById Long user id  doesn t get the information from database  it s just call user constructor  Why is it so   public User getUserById Long user id            Session session   null          User user   null          try               session   HibernateUtil getSessionFactory   openSession                user    session load User class                      user id               Hibernate initialize user             catch  Exception e                e printStackTrace              finally               if  session    null  amp  amp  session isOpen                      session close                                    return user

User · Accepted Answer

use get instead of load                   try               session   HibernateUtil getSessionFactory   openSession                user     User  session get User class  user id             catch  Exception e

User · Answer

In getUserById you shouldn t create a new object  user1  which isn t used  Just assign it to the already  but null  initialized user  Otherwise Hibernate initialize user   is actually Hibernate initialize null    Here s the new getUserById  I haven t tested this       public User getUserById Long user id        Session session   null      Object user   null      try           session   HibernateUtil getSessionFactory   openSession            user    User session load User class  user id           Hibernate initialize user         catch  Exception e           e printStackTrace          finally           if  session    null  amp  amp  session isOpen                  session close                        return user

User · Answer

Using EntityManager em   public User getUserById Long id         return em getReference User class  id

[java] Hibernate: get entity by id

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