保存对数据库 vaadin 的更改

Save changes to database vaadin(保存对数据库 vaadin 的更改)

问题描述

我有一个应用程序，它有一个表格，当您单击表格中的一个项目时，它会使用其数据(FieldGroup)填充一组文本字段，然后您可以选择保存更改我是想知道如何保存用户对我的 postgres 数据库所做的更改.我正在为这个应用程序使用 vaadin 和 hibernate.到目前为止，我已经尝试过

I have an application which has a table and when you click on an item in the table it fills in a group of textfields with its data (FieldGroup), and then you have the option of saving the changes I was wondering how would I save the changes the user makes to my postgres database. I am using vaadin and hibernate for this application. So far I have tried to do

   editorField.commit() // after the user clicks the save button

我试过了

   editorField.commit() 
   hbsession.persist(editorField) //hbsession is the name of my Session

我也试过了

   editorField.commit();
   hbsession.save(editorField);

最后两个给我以下错误

Caused by: org.hibernate.SessionException: Session is closed!

推荐答案

我已经弄清楚如何对数据库进行更改，这里有一些代码来演示:

I have figured out how to make changes to the database here is some code to demonstrate:

try {
  /** define the session and begin it **/
  hbsession = HibernateUtil.getSessionFactory().getCurrentSession();
  hbsession.beginTransaction();

  /** table is the name of the Bean class linked to the corresponding SQL table **/
  String query = "UPDATE table SET name = " + textfield.getValue();

  /** Run the string as an SQL query **/
  Query q = hbsession.createQuery(query);
  q.executeUpdate(); /** This command saves changes or deletes a entry in table **/

  hbsession.getTransaction().commit();
} catch (RuntimeException rex) {
    hbsession.getTransaction().rollback();
    throw rex;
}

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