hibernate 注解一个“分类”bean

目标表字段：
scheduletypeid     typename  typeparentid
1                  java       0
2                  javaEE     1
3                  javaME     1
4                  .net       0
5                  C#         4
6                  asp.net    4
@Entity
@Table(name = "ws_scheduletype")
public class ScheduleType implements java.io.Serializable{ private static final long serialVersionUID = 1L;
private int scheduletypeid;

private String typeName;

private ScheduleType typeparent; private Set<ScheduleType> typechildren; public ScheduleType() {
super();
} public int getScheduletypeid() {
return scheduletypeid;
} public void setScheduletypeid(int scheduletypeid) {
this.scheduletypeid = scheduletypeid;
} public String getTypeName() {
return typeName;
} public void setTypeName(String typeName) {
this.typeName = typeName;
}
@ManyToOne(cascade = {}, fetch = FetchType.LAZY)
@JoinColumns({
@JoinColumn(name = "typeparentid",nullable = false, insertable = true, updatable = true) 
})
public ScheduleType getTypeparent() {
return typeparent;
} public void setTypeparent(ScheduleType typeparent) {
this.typeparent = typeparent;
} @OneToMany(cascade = { CascadeType.MERGE }, fetch = FetchType.EAGER, mappedBy = "typeparent")
public Set<ScheduleType> getTypechildren() {
return typechildren;
} public void setTypechildren(Set<ScheduleType> typechildren) {
this.typechildren = typechildren;
}Exception :
Error creating bean with name 'sessionFactory' defined in file [D:\apache-tomcat-6.0.32\wtpwebapps\webvigator\WEB-INF\classes\spring\applicationContext-hibernate-dao.xml]: Invocation of init method failed; nested exception is org.hibernate.AnnotationException: No identifier specified for entity: com.company.project.model.ScheduleType
ps: 我有写这个
<property name="packagesToScan">
<list>
<value>com.**.model</value>
</list>
</property>