@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);