利用WSS做后台存储--设计一个统一的信息发布平台

方案设计：
功能包括：信息发布，保存，浏览，修改，查询
问题提出：信息发布内容和格式不能确定，应该允许客户定制信息（名称、类型、显示方式和布局）
每条目信息可以包含一个或多个附件。可以全文检索信息。
采用WSS做后台信息存储，针对于用户定义的信息内容包含数据字典为用户建立一个WSS中的“列表”和一个“文档库”，每条发布的信息存储在“列表”的一个item中，根据列表中每个Item的ID在文档库中建立一个以ID为名称的folder,在folder下存储该item的附件。
利用SPS的search webseivce进行检索

附部分类库源代码：
IPList类

namespace SPSInformationPublish
{
    /**//// <summary>
    ///操作信息发布＂列表＂的类
    /// </summary>
    public class IPList
    {
        域#region 域
        private string m_Guid;
        private string m_SiteUrl;
        private SPWeb m_CurrentWeb;
        private SPList m_SPList;
        private SPSite m_CurrentSite;
        private string defaultViewName = "DocManageDefaultView";
        #endregion
        属性#region 属性
        private SPList GetSPListByGUID(string guid,SPListCollection spLists)
        {
            try
            {
                return spLists.GetList(new Guid(guid),true);
            }
            catch
            {
                return null;
            }
        }
        
        public string Guid
        {
            get
            {
                return m_Guid;
            }
        }
        public SPWeb CurrentWeb
        {
            get
            {
                if (this.m_CurrentWeb == null)
                {
                    return CurrentSite.OpenWeb();
                }
                return m_CurrentWeb;
            }
        }
        public SPSite CurrentSite
        {
            get
            {
                if (this.m_CurrentSite == null)
                {
                    return GetSPSite();
                }
                else
                {
                    return m_CurrentSite;
                }
            }
            set
            {
                m_CurrentSite = value;
            }
        }
        public SPList ObjSPList
        {
            get
            {
                return GetSPListByGUID(Guid);
            }
            set
            {
                ObjSPList = value;
            }
        }
    
        #endregion
        构造器#region 构造器
        public IPList()
        {
            //
            // TODO: 在此处添加构造函数逻辑
            //
        }
        public IPList(string guid,string siteUrl)
        {
            m_Guid = guid;
            m_SiteUrl = siteUrl;
            m_CurrentSite = GetSPSite();
            m_CurrentWeb = m_CurrentSite.OpenWeb();
            
        }
        public IPList(SPList objSPList)
        {
            ObjSPList = objSPList;
            m_Guid = objSPList.ID.ToString();
            CurrentSite = objSPList.ParentWeb.Site;
            m_CurrentWeb = objSPList.ParentWeb;
        }
        #endregion
        私有方法#region 私有方法
        /**//// <summary>
        /// 为文档库新建一个字段
        /// </summary>
        /// <param name="FieldName">字段名</param>
        /// <param name="Type">字段类型，为SPFieldType枚举</param>
        /// <returns>bool</returns>
        private void CreateExtendField(string fieldName,string fieldTitle, SPFieldType type,string guid)
        {
            CurrentSite.AllowUnsafeUpdates = true;
            CurrentWeb.AllowUnsafeUpdates = true;
            SPFieldCollection fields = CurrentWeb.Lists[new Guid(guid)].Fields;
            fields.Add(fieldName,type,false);
            SPField fld=fields.GetField(fieldName);
            fld.Title=fieldTitle;
            fld.Update();            
            //将字段加入到视图中
            SPList list = CurrentWeb.Lists[new Guid(guid)];
            SPView view = list.DefaultView;
            SPViewFieldCollection viewFields = view.ViewFields;
            viewFields.Add(fieldName);
            view.Update();
        }
        #endregion 
        公共方法#region 公共方法
        文档库基本操作#region 文档库基本操作
        public SPSite GetSPSite()
        {
            return new SPSite(this.m_SiteUrl);
        }
        public SPList GetSPListByGUID(string guid)
        {
            try
            {
                return CurrentWeb.Lists.GetList(new Guid(guid),true);
            }
            catch
            {
                return null;
            }
        }
        public void Create(string title,string description ,ArrayList objExtendFields)
        {
            string id = this.Create(title,description);
            CreateView(id);
            CreateExtendFields(objExtendFields,id);
        }
        public string Create(string title,
            string description
            )
        {
            try
            {
                CurrentSite.AllowUnsafeUpdates = true;
                CurrentWeb.AllowUnsafeUpdates = true;
                SPListCollection lists = CurrentWeb.Lists;
                Guid id = lists.Add(title, description, SPListTemplateType.GenericList);
                return id.ToString();
                
            }
            catch(Exception e)
            {
                throw new Exception("创建文档库出错！" + e.ToString());
            }
        }
        public string Create(string title,
            string description ,
            bool enableVersion )
        {
            try
            {
                CurrentSite.AllowUnsafeUpdates = true;
                CurrentWeb.AllowUnsafeUpdates = true;
                SPListCollection lists = CurrentWeb.Lists;
                Guid id = lists.Add(title, description, SPListTemplateType.GenericList);
                SPList list = CurrentWeb.Lists[id];
                list.EnableVersioning = enableVersion;
                list.Update();
                return id.ToString();
            }
            catch(Exception e)
            {
                throw new Exception("创建文档库出错！" + e.ToString());
            }
        }
        public void Delete(string guid)
        {
            try
            {
                CurrentSite.AllowUnsafeUpdates = true;
                CurrentWeb.AllowUnsafeUpdates = true;
                CurrentWeb.Lists.Delete(new Guid(guid));
            }
            catch(Exception e)
            {
                throw new Exception("删除文档库（GUID：" + guid + "）出错！" + e.ToString());
            }
        }
        

        #endregion
        扩展字段操作#region 扩展字段操作
        /**//// <summary>
        /// 
        /// </summary>
        /// <param name="objExtendFields"></param>
        public void CreateExtendFields(ArrayList objExtendFields,string guid)
        {
            IEnumerator objenum = objExtendFields.GetEnumerator();
            while (objenum.MoveNext())
            {
                ExtendFieldsInfo fieldInfo = objenum.Current as ExtendFieldsInfo;
                if (fieldInfo != null)
                {
                    CreateExtendField(fieldInfo.ExtendFieldCode,
                        fieldInfo.ExtendFieldName,
                        IPExtendFieldDataType.GetType(fieldInfo.ExtendFieldDataType),
                        guid );
                }
            }
        }
        public void CreateView(string guid)
        {
            CurrentSite.AllowUnsafeUpdates = true;
            CurrentWeb.AllowUnsafeUpdates = true;
            SPListCollection lists = CurrentWeb.Lists;
            SPList list = lists[new Guid(guid)];
            SPViewCollection views = list.Views;
            StringCollection viewFields = new StringCollection();
            string viewName = defaultViewName;
            viewFields.Add("ID");
            viewFields.Add("Author");
            viewFields.Add("Created");
            viewFields.Add("Modified");
            viewFields.Add("Title");
            string query = "";
            views.Add(viewName, viewFields, query, 300, true, true);
        }
        #endregion
        获取数据列表操作#region 获取数据列表操作

        public DataView GetListItem()
        {
            
            DataView dv = ObjSPList.GetItems(ObjSPList.DefaultView).GetDataTable().DefaultView;
            dv.Sort = "Created Desc";
            return dv;
        }
        public DataView GetListItem(IFilter filter)
        {
            DataView dv = ObjSPList.GetItems(filter.ToQuery()).GetDataTable().DefaultView;
            dv.Sort = "Created Desc";
            return dv;
        }
        /**//// <summary>
        /// 按条件直接从SPS数据库UserData表中查找数据
        /// </summary>
        /// <param name="filter"></param>
        /// <param name="dbSPS"></param>
        /// <returns></returns>
        public DataSet GetListItem(IFilterDB dbFilter,DataBase dbSPS)
        {
            try
            {
                return dbSPS.RunProc(dbFilter.ToQuerySqlString(),new DataSet());
            }
            catch(Exception e)
            {
                throw new Exception("构造SQL语句出错：" + dbFilter.ToQuerySqlString() + "错误源：" + e.ToString());
            }
        }
        #endregion
        统计信息#region 统计信息
        public int GetTotal(IFilterDB dbFilter,DataBase dbSPS)
        {
            try
            {
                 return int.Parse(dbSPS.ReturnValue(dbFilter.ToCountSqlString()));
            }
            catch(Exception e)
            {
                throw new Exception("构造SQL语句出错：" + dbFilter.ToQuerySqlString() + "错误源：" + e.ToString());
            }
        }

        #endregion

        #endregion 
    }
}

类IPListAttach

namespace SPSInformationPublish
{
    /**//// <summary>
    /// 操作信息发布附件的类
    /// </summary>
    public class IPListAttach
    {
        private SPSite m_CurrentSite;
        private SPWeb m_CurrentWeb;
        private string m_Guid;
        private string m_SiteUrl;
        private SPDocumentLibrary m_DL;
        private string defaultViewName = "DocManageDefaultView";
        private DocumentLibrary m_ProxyDL;
        public DocumentLibrary ProxyDL
        {
            get
            {
                if (m_ProxyDL != null)
                {
                    return m_ProxyDL;
                }
                return new DocumentLibrary(this.m_SiteUrl,this.m_Guid,true);
            }
        }
        public IPListAttach(string guid,string siteUrl)
        {
            m_Guid = guid;
            m_SiteUrl = siteUrl;
            m_CurrentSite = GetSPSite();
            m_CurrentWeb = m_CurrentSite.OpenWeb();
            m_DL = (SPDocumentLibrary)GetSPListByGUID(guid);
        }
        public SPList GetSPListByGUID(string guid)
        {
            try
            {
                return m_CurrentWeb.Lists.GetList(new Guid(guid),true);
            }
            catch
            {
                return null;
            }
        }
        public SPSite GetSPSite()
        {
            return new SPSite(m_SiteUrl);
        }
        public void Create(string title,string description ,ArrayList objExtendFields)
        {
            string id = Create(title,description);
            CreateView(id);
            CreateExtendFields(objExtendFields,id);
        }
        public void CreateExtendFields(ArrayList objExtendFields,string guid)
        {
            IEnumerator objenum = objExtendFields.GetEnumerator();
            while (objenum.MoveNext())
            {
                ExtendFieldsInfo fieldInfo = objenum.Current as ExtendFieldsInfo;
                if (fieldInfo != null)
                {
                    CreateExtendField(fieldInfo.ExtendFieldCode,
                        fieldInfo.ExtendFieldName,
                        IPExtendFieldDataType.GetType(fieldInfo.ExtendFieldDataType),
                        guid );
                }
            }
        }
        private void CreateExtendField(string fieldName,string fieldTitle, SPFieldType type,string guid)
        {
            this.m_CurrentSite.AllowUnsafeUpdates = true;
            this.m_CurrentWeb.AllowUnsafeUpdates = true;
            SPFieldCollection fields = m_CurrentWeb.Lists[new Guid(guid)].Fields;
            fields.Add(fieldName,type,false);
            SPField fld=fields.GetField(fieldName);
            fld.Title=fieldTitle;
            fld.Update();            
            //将字段加入到视图中
            SPList list = m_CurrentWeb.Lists[new Guid(guid)];
            SPView view = list.DefaultView;
            SPViewFieldCollection viewFields = view.ViewFields;
            viewFields.Add(fieldName);
            view.Update();
        }
        public void CreateView(string guid)
        {
            this.m_CurrentSite.AllowUnsafeUpdates = true;
            this.m_CurrentWeb.AllowUnsafeUpdates = true;
            SPListCollection lists = m_CurrentWeb.Lists;
            SPList list = lists[new Guid(guid)];
            SPViewCollection views = list.Views;
            StringCollection viewFields = new StringCollection();

            string viewName = defaultViewName;
            viewFields.Add("DocIcon");
            viewFields.Add("LinkFilename");
            viewFields.Add("Last_x0020_Modified");
            viewFields.Add("Editor");
            viewFields.Add("ID");
            viewFields.Add("Author");
            viewFields.Add("Created_x0020_Date");
            viewFields.Add("FileLeafRef");
            viewFields.Add("LinkFilenameNoMenu");
            viewFields.Add("FileSizeDisplay");
            viewFields.Add("Title");
            string query = "";
            views.Add(viewName, viewFields, query, 300, true, true);
        }
        public string Create(string title,
            string description
            )
        {
            try
            {
                m_CurrentSite.AllowUnsafeUpdates = true;
                m_CurrentWeb.AllowUnsafeUpdates = true;
                SPListCollection lists = m_CurrentWeb.Lists;
                Guid id = lists.Add(title, description, SPListTemplateType.DocumentLibrary);
                return id.ToString();
                
            }
            catch(Exception e)
            {
                throw new Exception("创建文档库出错！" + e.ToString());
            }
        }
        public string CreateDocumentLibrary(string SiteURL,
            string docTitle,
            string docDescription,
            bool VersionControl)
        {
            return null;
        }
        public void Delete(int id)
        {
            this.ProxyDL.DeleteFolder(id.ToString());
        }
        public void CreateFolder(int id)
        {
        }
        public bool HasAttach(int id)
        {
            try
            {
                if(ProxyDL.GetFolder(id.ToString()).Files.Count > 0)
                    return true;
                else
                    return false;
            }
            catch
            {
                return false;
            }
        }
        public void AddAttach(int id)
        {
        }
        public void Delete(string guid)
        {
            try
            {
                this.m_CurrentSite.AllowUnsafeUpdates = true;
                this.m_CurrentWeb.AllowUnsafeUpdates = true;
                this.m_CurrentWeb.Lists.Delete(new Guid(guid));
            }
            catch(Exception e)
            {
                throw new Exception("删除文档库（GUID：" + guid + "）出错！" + e.ToString());
            }
        }
        /**//// <summary>
        /// 把附件添加到SPS文档库中
        /// </summary>
        public int  AddToDocLib(int id,byte[] fileConent,string fileName,Hashtable inputFields)
        {
            try
            {
                //CreateFolder(dl,dl.docLibrary.Title,taskID.ToString());
                ProxyDL.web.AllowUnsafeUpdates = true;
                SPFileCollection files = ProxyDL.GetFolder(ProxyDL.docLibrary.Title + "/" + id.ToString()).Files;
                SPFile myFile  = files.Add(ProxyDL.SiteURL + "/" + ProxyDL.docLibrary.Title +
                    "/" + id.ToString() + "/" + fileName ,fileConent,true);
                UpdateItem(myFile.Item.ID,inputFields);
                return myFile.Item.ID;
            }
            catch(Exception e)
            {
                throw e;
            }
        }
        public void DeleteFromDocLibByItemID(int itemID)
        {
            ProxyDL.web.AllowUnsafeUpdates = true;
            ProxyDL.DocLibrary.Items.DeleteItemById(itemID);
            
        }
        /**//// <summary>
        /// 更新扩展字段
        /// </summary>
        /// <param name="itemID"></param>
        /// <param name="inputFields"></param>
        private void UpdateItem(int itemID,Hashtable inputFields)
        {
            SPListItem item = ProxyDL.DocLibrary.Items.GetItemById(itemID);

            IDictionaryEnumerator myEnumerator = inputFields.GetEnumerator();
            while (myEnumerator.MoveNext())
            {
                item[myEnumerator.Key.ToString()] = myEnumerator.Value.ToString();
            }
            item.Update();
        }
        /**//// <summary>
        /// 得到一个列表条目下的附件列表
        /// </summary>
        /// <param name="id">列表ID</param>
        /// <returns></returns>
        public DataView GetDataViewFromFolder(int id)
        {
            try
            {
                //创建记录集对象
                DataSet Ds = ProxyDL.GetItem(ProxyDL.DocLibrary.Title + "/" + id.ToString());
                DataView DV = new DataView() ;
                if(Ds.Tables.Count > 0)
                {
                    //过滤掉目录
                    DV = new DataView(Ds.Tables[0],"DocIcon <> ''","",DataViewRowState.CurrentRows);
                    DV.Sort = "Last_x0020_Modified Desc";
                }
                return DV;
            }
            catch(Exception Err)
            {
                throw Err;
                return null;
            }
        }
    }
}

IListItem

namespace SPSInformationPublish
{
    /**//// <summary>
    /// 操作信息发布item类
    /// </summary>
    public class IPListItem
    {
        private IPList m_IPList;
        private IPListAttach m_IPListAttach;
        public IPList List
        {
            get
            {
                return this.m_IPList;
            }
        }
        public IPListAttach ListAttach
        {
            get
            {
                return this.m_IPListAttach;
            }
        }
        public IPListItem(IPList objList,IPListAttach objAttach)
        {
            m_IPList = objList;
            m_IPListAttach = objAttach;
        }
        public void TransferHasAttachStatus(int id ,string hasAttachFieldName )
        {
            if (ListAttach.HasAttach(id))
            {
                SetHasAttach(id,hasAttachFieldName);
            }
            else
            {
                SetNoneAttach(id,hasAttachFieldName);
            }
        }
        /**//// <summary>
        /// 添加一条记录
        /// </summary>
        /// <param name="inputFields"></param>
        /// <returns></returns>
        public int Add(Hashtable inputFields)
        {
            SPListItem item = List.ObjSPList.Items.Add();
            IDictionaryEnumerator myEnumerator = inputFields.GetEnumerator();
            while (myEnumerator.MoveNext())
            {
                item[myEnumerator.Key.ToString()] = myEnumerator.Value.ToString();
            }
            item.Update();
            ProxyCreateFolder(item.ID);
            ProxyAddAttach(item.ID);
            return item.ID;
        }
        /**//// <summary>
        /// 修改一条记录
        /// </summary>
        /// <param name="id"></param>
        /// <param name="inputFields"></param>
        public void Update(int id,Hashtable inputFields)
        {
            SPListItem item = List.ObjSPList.Items.GetItemById(id);
            IDictionaryEnumerator myEnumerator = inputFields.GetEnumerator();
            while (myEnumerator.MoveNext())
            {
                item[myEnumerator.Key.ToString()] = myEnumerator.Value.ToString();
            }
            item.Update();
        }
        /**//// <summary>
        /// 删除一个记录
        /// </summary>
        /// <param name="id"></param>
        public void Delete(int id)
        {
            List.ObjSPList.Items.DeleteItemById(id);
            //删除附件
            ListAttach.Delete(id);
        }
        private void ProxyCreateFolder(int id)
        {
            ListAttach.CreateFolder(id);
        }
        private void ProxyAddAttach(int id)
        {
            ListAttach.AddAttach(id);
        }
        private void SetHasAttach(int id,string hasAttachFieldName)
        {
            Hashtable ht = new Hashtable();
            ht.Add(hasAttachFieldName,true);
            Update(id,ht);
        }
        private void SetNoneAttach(int id,string hasAttachFieldName)
        {
            Hashtable ht = new Hashtable();
            ht.Add(hasAttachFieldName,false);
            Update(id,ht);
        }
    }
}

IPFacadeFactory

namespace SPSInformationPublish
{
    /**//// <summary>
    /// 外部调用程序通过本类统一访问此类库功能
    /// </summary>
    public class IPFacadeFactory
    {
        private IPFacadeFactory()
        {
            //
            // TODO: 在此处添加构造函数逻辑
            //
        }
        /**//// <summary>
        /// 返回listitem对象
        /// </summary>
        /// <param name="listGuid">列表对象的GUID</param>
        /// <param name="attachGuid">附件文档库的GUID</param>
        /// <param name="siteUrl">站点的Url</param>
        /// <returns></returns>
        public static IPListItem Create(string listGuid,
            string attachGuid,
            string siteUrl
            )
        {
            return new IPListItem(CreateIPList(listGuid,siteUrl),
                CreateAttachList(attachGuid,siteUrl));
        }
        /**//// <summary>
        /// 返回IPList对象
        /// </summary>
        /// <param name="guid"></param>
        /// <param name="siteUrl"></param>
        /// <returns></returns>
        public static IPList CreateIPList(string guid,string siteUrl)
        {
            return new IPList(guid,siteUrl);
        }
        /**//// <summary>
        /// 返回IPList对象（没有实力化列表对象，Add时候使用)
        /// </summary>
        /// <param name="siteUrl"></param>
        /// <returns></returns>
        public static IPList CreateIPList(string siteUrl)
        {
            return CreateIPList("",siteUrl);
        }
        /**//// <summary>
        /// 返回AttachList对象
        /// </summary>
        /// <param name="guid"></param>
        /// <param name="siteUrl"></param>
        /// <returns></returns>
        public static IPListAttach CreateAttachList(string guid,string siteUrl)
        {
            return new IPListAttach(guid,siteUrl);
        }
    }
}

直接从sps数据库中检索数据

using System;
using System.Data;
using System.Collections;
using System.Text;
using UltraPower.SPS.DB;

namespace SPSInformationPublish
{
    /**//// <summary>
    /// FilterDB 的摘要说明。
    /// </summary>
    public class FilterDB : IFilterDB
    {
        private string m_ListGuid;
        private string m_ConnStr;
        private SpsExpendFields m_SpsExpendFields;
        private ArrayList m_SelectFields;
        private ArrayList m_WhereFields;
        private string m_Where;
        private ArrayList m_OrderByFields;
        public SpsExpendFields ExpendFields
        {
            get
            {
                if (m_SpsExpendFields != null)
                {
                    return m_SpsExpendFields;
                }
                return new SpsExpendFields(m_ConnStr,m_ListGuid);
            }
        }
        构造器#region 构造器
        public FilterDB(string guid,
            ArrayList select,
            ArrayList whereFields,
            string where,
            ArrayList orderBy,
            string connStr)
        {
            m_ListGuid = guid;
            m_ConnStr = connStr;
            m_SelectFields = select;
            m_WhereFields = whereFields;
            this.m_Where = where;
            m_OrderByFields = orderBy;
        }
        public FilterDB(string guid,
            ArrayList select,
            ArrayList whereFields,
            string where,
            string connStr)
        {
            m_ListGuid = guid;
            m_ConnStr = connStr;
            m_SelectFields = select;
            m_WhereFields = whereFields;
            this.m_Where = where;
            
        }
        public FilterDB(string guid,
            ArrayList whereFields,
            string where,
            string connStr)
        {
            m_ListGuid = guid;
            m_ConnStr = connStr;
            m_WhereFields = whereFields;
            this.m_Where = where;
        }
        public FilterDB(string guid,string connStr)
        {
            m_ListGuid = guid;
            m_ConnStr = connStr;
        }
        #endregion
        私有方法#region 私有方法

        private string GetOrderBy()
        {
            StringBuilder sb = new StringBuilder();
            if (this.m_OrderByFields == null)
            {
                return "";
            }
            if (this.m_OrderByFields.Count == 0)
            {
                return "";
            }
            if (this.m_OrderByFields.Count == 1)
            {
                return this.GetDBField(this.m_OrderByFields[0].ToString());
            }
            else
            {
                for(int i=0;i<this.m_OrderByFields.Count;i++)
                {
                    if (i == 0)
                    {
                        sb.Append(" " + GetDBField(this.m_OrderByFields[i].ToString()));
                    }
                    else
                    {
                        sb.Append("," +  GetDBField(this.m_OrderByFields[i].ToString()));
                    }
                }
                return " Order By " + sb.ToString();
            }
            
        }
        private string GetSelect()
        {
            StringBuilder sb = new StringBuilder();
            sb.Append(" Select '0',");
            for(int i = 0;i< m_SelectFields.Count;i++)
            {
                sb.Append(" " + this.GetDBField(m_SelectFields[i].ToString()) + 
                    " As " + m_SelectFields[i].ToString() + ",");
            }
            sb.Append(" '1' ");
            sb.Append(" From UserData ");

            return sb.ToString();
        }
        private string GetWhere()
        {
            if (this.m_Where.Trim()=="")
            {
                return "Where tp_ListID = '" + m_ListGuid + "'" ;
            }
            StringBuilder sb = new StringBuilder();
            for(int i=0;i<this.m_WhereFields.Count;i++)
            {
                m_Where = m_Where.Replace(this.m_WhereFields[i].ToString(),this.GetDBField(m_WhereFields[i].ToString()));
            }
            sb.Append(" Where (" + this.m_Where + ") "); 
            sb.Append(" And tp_ListID = '" + m_ListGuid + "'");
            return sb.ToString();
        }
        private bool IsDBField(string field)
        {
            return true;
        }
        private bool IsSPSExpendField(string field)
        {
            return true;
        }
        private string GetDBField(string spsExpendField)
        {
            return ExpendFields.GetDBFieldName(spsExpendField);
        }
        #endregion
        IFilterDB 成员#region IFilterDB 成员

        public string ToQuerySqlString()
        {
            // TODO:  添加 FilterDB.ToQuerySqlString 实现
            return GetSelect() + " " + GetWhere() + " " + GetOrderBy();
        }
        public string ToCountSqlString()
        {
            return "Select Count(*) as total From UserData " + " " + GetWhere() + " " ;

        }

        #endregion
    }
}

类图：