Hibernate联合主键查询报错,该如何处理

@Entity@Table(name="student")@IdClass(StudentPK.class)public class Student {    @Id    public int getId() {        return id;    }    @Id    public String getName() {        return name;    }   ...}StudentPK.java:   public class StudentPK implements java.io.Serializable{    private int id;    private String name;    ...   }

session1.beginTransaction();        StudentPK pk = new StudentPK();        pk.setId(1);        pk.setName("Hiway");        Student s = (Student) session1.get(StudentPK.class, pk);        System.out.println(s);