hibernate别名Alias
实体:考试,成绩,学生,班级
关系:成绩与考试多对一,成绩与学生多对一,学生与班级多对一.
需求:要根据考试id和班级id查询学生成绩.

Score

@Entity  public class Score {        private int id;        private Student student;        private Exam exam;        private int score;        @Id      @GeneratedValue(strategy = GenerationType.IDENTITY)      public int getId() {          return id;      }        public void setId(int id) {          this.id = id;      }        @ManyToOne      @JoinColumn(name = "studentid", referencedColumnName = "id")      public Student getStudent() {          return student;      }        public void setStudent(Student student) {          this.student = student;      }        @ManyToOne      @JoinColumn(name = "examid", referencedColumnName = "id")      public Exam getExam() {          return exam;      }        public void setExam(Exam exam) {          this.exam = exam;      }        public int getScore() {          return score;      }        public void setScore(int score) {          this.score = score;      }    }  

Student

private int id;        private Grade grade;        private String name;      @Id      @GeneratedValue(strategy = GenerationType.IDENTITY)      public int getId() {          return id;      }        public void setId(int id) {          this.id = id;      }        @ManyToOne      @JoinColumn(name = "gradeid", referencedColumnName = "id")      public Grade getGrade() {          return grade;      }        public void setGrade(Grade grade) {          this.grade = grade;      }        public String getName() {          return name;      }        public void setName(String name) {          this.name = name;      }  

Exam和Grade略

下面是查询代码.
ScoreDao:

@SuppressWarnings("unchecked")      public List<Score> getList(int examid, int gradeid) {          Criteria c = getSession().createCriteria(Score.class);          c.setFetchMode("exam", FetchMode.JOIN);          c.add(Restrictions.eq("exam.id", examid));          c.createAlias("student.grade", "grade");          c.add(Restrictions.eq("grade.id", gradeid));            return c.list();      }  

转自：http://www.verydemo.com/demo_c146_i2502.html