異常在線程 「主要」 org.hibernate.ObjectNotFoundException：沒有排與所述給定的標識符存在：[com.mycompany.Contact＃8]

Question

public class ContactManager { 

    public static void main(String[] args) { 
     // loads configuration and creates a session factory 
     Configuration configuration = new Configuration().configure(); 
     ServiceRegistryBuilder registry = new ServiceRegistryBuilder(); 
     registry.applySettings(configuration.getProperties()); 
     ServiceRegistry serviceRegistry = registry.buildServiceRegistry(); 
     SessionFactory sessionFactory = configuration.buildSessionFactory(serviceRegistry); 

     // opens a new session from the session factory 
     Session session = sessionFactory.openSession(); 
     session.beginTransaction(); 

     // persists two new Contact objects 
     Contact contact1 = new Contact("Nam", "hainatu@gmail.com", "Vietnam", "0904277091"); 
     session.persist(contact1); 

     Contact contact2 = new Contact("Bill", "bill@gmail.com", "USA", "18001900"); 
     Serializable id = session.save(contact2); 
     System.out.println("created id: " + id); 

     // loads a new object from database 
     Contact contact3 = (Contact) session.get(Contact.class, new Integer(1)); 
     if (contact3 == null) { 
      System.out.println("There is no Contact object with id=1"); 
     } else { 
      System.out.println("Contact3's name: " + contact3.getName()); 
     } 

     // loads an object which is assumed exists 
     Contact contact4 = (Contact) session.load(Contact.class, new Integer(1)); 
     System.out.println("Contact4's name: " + contact4.getName()); 
// updates a loaded instance of a Contact object 
     Contact contact5 = (Contact) session.load(Contact.class, new Integer(2)); 
     contact5.setEmail("info1@company.com"); 
     contact5.setTelephone("1234567890"); 
     session.update(contact5); 

ERROR：

Hibernate: select max(CONTACT_ID) from CONTACT 
created id: 2 
Contact3's name: Nam 
Contact4's name: Nam 
Hibernate: select contact0_.CONTACT_ID as CONTACT1_0_0_, contact0_.NAME as NAME0_0_, contact0_.email as email0_0_, contact0_.address as address0_0_, contact0_.telephone as telephone0_0_ from CONTACT contact0_ where contact0_.CONTACT_ID=? 
Exception in thread "main" org.hibernate.ObjectNotFoundException: No row with the given identifier exists: [com.mycompany.Contact#8] 

Answer 1

使用id通過session.save(contact2)返回在你的load()方法中從數據庫中獲取它。它應該工作。

Contact contact5 = (Contact) session.load(Contact.class, id);