隨筆分類(157)

刪除
DAO代碼：
 public void delete(Integer lid) {
        log.debug("deleting Login instance");
        try {
         Login login=(Login)this.getHibernateTemplate().load(Login.class,lid);
            getHibernateTemplate().delete(login);
            log.debug("delete successful");
        } catch (RuntimeException re) {
            log.error("delete failed", re);
            throw re;
        }
    }

調用DAO：
Integer selid = Integer.valueOf(request.getParameter("select"));
loginDAO.delete(selid);

批量刪除
需要注意的是in后面跟的是字符串，如果不是會提示org.hibernate.QueryException: unexpected char: ';'的出錯
DAO代碼：
public void delete(String[] lid) {
    String[] ids = lid;
         String str="";
         for(int i=0;i<ids.length;i++){
             str+="'"+ids[i]+"'";
             if(i!=(ids.length-1))
                 str+=",";
             }
  List list   =   this.getHibernateTemplate().find("from Login where id in ("+str+")");
  if(list.size()>0){  
     this.getHibernateTemplate().deleteAll(list);
     }
 }

或者可以這樣寫：
  public void batchDelete(String[] lid) {
      String[] ids = lid;
           for(int i=0;i<ids.length;i++){
               log.debug("deleting Login instance");
            try {
             TPhotoclass tTPhotoclass=(TPhotoclass)this.getHibernateTemplate().load(TPhotoclass.class,Long.parseLong(ids[i]));
                getHibernateTemplate().delete(tTPhotoclass);
                log.debug("delete successful");
            } catch (RuntimeException re) {
                log.error("delete failed", re);
                throw re;
            }
               }
   }


調用DAO：
String[] lid = request.getParameterValues("select");
loginDAO.delete(lid);