Hibernate count method: returns the number of attributes

count(String propertyName)

Example

Criteria criteria = session.createCriteria(UserForm.class);  //定义Criteria对象
criteria.setProjection(Projections.count("id"));  //返回属性数目
int max = (Integer)criteria.uniqueResult();  //获取查询结果
System.out.println("记录数:"+max);

Typical application

public static void main(String[] args){
  Session session = null;  //声明Session对象
  try{
    session = HibernateUtil.getSession();  //获取Session
    session.beginTransaction();  //开启事务
    try{
      Criteria criteria = session.createCriteria(Users.class);  //定义Criteria对象
      criteria.setProjection(Projections.count("id"));  //返回属性数目
      int max = (Integer)criteria.uniqueResult();  //获取查询结果
      System.out.println("tb_users表的记录数为:"+max);
    }catch(Exception e){
      System.out.println("查询用户信息时的错误信息:"+e.getMessage());
    }
    session.getTransaction().commit();  //提交事务
  }catch(Exception e){
    e.printStackTrace();
    session.getTransaction().rollback();  //出错将回滚事务
  }finally{
    HibernateUtil.closeSession(session);  //关闭Session对象
  }
}