Hibernate标准查询多个条件 [英] Hibernate criteria query multiple criteria

问题描述

在我目前的项目中，我遇到了使用hibernate标准查询获取实体的问题。我有以下实体：

• 教授，其中包含学生列表


• 学生，其中包含分配列表。


• 分配，其中包含分配给其的学生的ID。

现在，我想要获得与教授相关的所有作业，即分配给他的学生的所有作业教授。

这个查询显示了我想要实现的内容标准查询。

  select * from Assigment p，Student a，Professor c其中p.studentid = a.id和a.proffid = c.id和c.id = 2411; 
  

如何使用hibernate标准API实现此查询？

  @Entity 
公开课教授{
 K id; 
列表< Student>学生们; 
} 
 
 @实体
公共类学生{
 K profid; 
列表< Assignments>任务; 
} 
 
 @实体
公共类赋值{
 K studentid; 
 
  

使用别名的简单示例：

  Criteria criteria = currentSession.createCriteria（Professor.class，professor）; 
 criteria.createAlias（professor.students，student）; 
 criteria.createAlias（student.assigments，assigment）; 
 criteria.add（Restrictions.eqProperty（professor.id，student.profid））; 
 criteria.add（Restrictions.eqProperty（assigment.studentid，student.profid））; 
 criteria.add（Restrictions.eq（id，2411））; 
 return criteria.list（）; 
  

In my current project I've faced a problem of getting entities with hibernate criteria query. I have the following entities:

• Professor, which contains a list of students
• Student, which contains a list of assignments.
• Assignment, which contains id of student to which it is assigned to.

Now, I want to get all assignments relative to the professor, i.e. all assignments Professor assigned to his students.

This query shows what I want to implement in criteria query.

select * from Assigment p, Student a, Professor c where p.studentid = a.id and a.proffid = c.id and c.id = 2411;

How can I implement this query using hibernate criteria API?

解决方案

suppose your tables like that:

@Entity
public class Professor{
    K id;
    List<Student> students;
}

@Entity
public class Student{
    K profid;
    List<Assignments> assignments;
}

@Entity
public class Assignments{
    K studentid;
}

simple sample by using alias:

Criteria criteria = currentSession.createCriteria(Professor.class, "professor");
    criteria.createAlias("professor.students", "student");
    criteria.createAlias("student.assigments", "assigment");
    criteria.add(Restrictions.eqProperty("professor.id", "student.profid"));
    criteria.add(Restrictions.eqProperty("assigment.studentid", "student.profid"));
    criteria.add(Restrictions.eq("id", 2411));
return criteria.list();

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