递归

public ShipType findById(String id){
return (ShipType)helper.getCurrentSession().get(ShipType.class, id);
}
private String getParent(String id,StringBuffer path){
ShipType st = findById(id);
if(st.getParentId() != null){
path.insert(0,"/"+st.getParentId());
getParent(st.getParentId(),path);
}
return path.toString();
}

public String getParentPath(String id) {
StringBuffer path = new StringBuffer();
path.append("/"+id+"/");
return getParent(id,path);
}