iBATIS+Oracle實現BLOB數據類型的存取

• 將一個Java對象列表存儲在Oracle的BLOB類型中

DAO實現中的寫法：

public void saveDsPPPs(Long dataFileId, ArrayList<PPP> list) { try { ByteArrayOutputStream bo = new ByteArrayOutputStream(); ObjectOutputStream oo = new ObjectOutputStream(bo); oo.writeObject(list); byte[] bytes = bo.toByteArray(); HashMap map = new HashMap(); map.put("dataFileId", dataFileId); map.put("pppList", bytes); pppId = (Long) getSqlMapClientTemplate().insert("addPPPs", map); catch (IOException e) { } }

注意事項：

PPP對象必須實現Serializable接口，可以序列化的對象才能轉成byte數組，否則會出錯

 

sqlMap中的寫法：

<insert id="addPPPs" parameterClass="java.util.HashMap" > <!--[CDATA[ insert into ppp (data_file_id,ppp_list) values (dataFileId#,#pppList#) ]]--> </insert>

 

• 返回BLOB數據轉換成Java對象列表

DAO實現中的寫法：

public ArrayList<PPP> getPPPs(Long dataFileId) { try { HashMap map = (HashMap) getSqlMapClientTemplate().queryForObject("getPPPs", dataFileId); BLOB blob = (BLOB) map.get("pppList"); ObjectInputStream objStream = new ObjectInputStream(blob.getBinaryStream()); ArrayList<PPP> pppList = (ArrayList<PPP>) objStream.readObject(); objStream.close(); return pppList; } catch (IOException e) { } catch (ClassNotFoundException e) { } catch (SQLException e) { } return null; }

sqlMap中寫法：

<resultMap id="pppResult" class="java.util.HashMap"> <result property="dataFileId" column="data_File_Id"/> <result property="pppList" column="ppp_List"/> </resultMap> <select id="getPPPs" parameterClass="java.lang.Long" resultMap="pppResult"> <!--[CDATA[ select * from ds_ppp where data_file_id = #value# ]]--> </select>