我在 hibernate 时遇到问题,但我不明白这个问题到底是什么 如果你有什么想法?
private SessionFactory sessionFactory;
@SuppressWarnings("unchecked")
public List<Customer> listCustomer() {
return sessionFactory.getCurrentSession().createQuery("FROM customer").list();
}
Main.java
public class Main {
public static void main(String[] args) {
CustomerDaoImpl dao=new CustomerDaoImpl();
for(int i=0; i<dao.listCustomer().size(); i++){
System.out.println(i);
}
}
}
错误
Exception in thread "main" java.lang.NullPointerException
at com.apps.dao.CustomerDaoImpl.listCustomer(CustomerDaoImpl.java:37)
at com.apps.dao.Main.main(Main.java:8)
最佳答案
您必须初始化您的sessionFactory
。在早期的 hibernate 版本中,您是这样做的
SessionFactory sessionFactory = new Configuration().configure().buildSessionFactory();
从 4.3.0 版本开始。你必须这样做
Configuration configuration = new Configuration().configure();
StandardServiceRegistryBuilder builder = new StandardServiceRegistryBuilder().
applySettings(configuration.getProperties());
SessionFactory sessionFactory = configuration.buildSessionFactory(builder.build());
关于java - hibernate SessionFactory 不起作用,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/27648849/