这次项目，我可以被oralce气伤了。Oracle 9i怎么会有那么多问题，驱动怎么会有那么多问题。 好了，说问题吧。 这次的问题集中读写oracle的blob、clob字段上。 1，读写blob需要一个lobhander，虽然defaultlobhander可以用于大多数数据库和大多数oracle的版本，却不能用过oracle 9i。我需要一个oraclelobhander。 以下是sPRing中的配置。
<bean id="oracleLobHandler" class="org.springframework.jdbc.support.lob.OracleLobHandler" singleton="false"><property name="nativeJdbcExtractor" ref="nativeJdbcExtractor"/> </bean><bean id="nativeJdbcExtractor" class="org.springframework.jdbc.support.nativejdbc.C3P0NativeJdbcExtractor" lazy-init="true"/> 以下是dao中的片段 /** * 更新指定的blob * @param key * @param contentStream * @param contentLength */public void updateBlog(final String key, final InputStream contentStream,final int contentLength) {logger.debug("update content");try {getJdbcTemplate().execute("update table set content = ? where id = ?",new AbstractLobCreatingPreparedStatementCallback(this.lobHandler) {protected void setValues(PreparedStatement ps,LobCreator lobCreator) throws SQLException {lobCreator.setBlobAsBinaryStream(ps, 1,contentStream, contentLength);ps.setString(2, key);}});} catch (RuntimeException re) { logger.warn("update content fail"); throw re; } } /** * 取得指定的blob * @param name * @param contentStream * @throws DataaccessException */ public void getBlobContent(final String id, final OutputStream contentStream) throws DataAccessException {getJdbcTemplate().query("SELECT content FROM table WHERE id=?", new String[] {id},new AbstractLobStreamingResultSetExtractor() {protected void handleNoRowFound() throws LobRetrievalFailureException {throw new IncorrectResultSizeDataAccessException("Image with id '" + id + "' not found in database", 1, 0);}public void streamData(ResultSet rs) throws SQLException, IOException {InputStream is = lobHandler.getBlobAsBinaryStream(rs, 1);if (is != null) {FileCopyUtils.copy(is, contentStream);}}}); } 前一个方法是写blob，后一个读blob。后面一个在业务方法中，这样用。
public void getBlobContent(HttpServletRequest request,HttpServletResponse response) {try {serviceDisplayDAO.getBlobContent(request.getParameter("id"),response.getOutputStream());} catch (DataAccessException e) {e.printStackTrace();
} catch (IOException e) {e.printStackTrace();} } 在页面中只需要做个链接：href="/blob.do?action=getBlogContent&id='"+id+"'" 2，读写clob 这个要简单一些，不过要需要oracle的驱动不能用class12.zip那个，要从oracle下一个新的版本，具体多少不记得了。 /** * 基于主键的查询方法 根据给出的主键查询一个业务并返回 * * @param key * @return */public List findByPrimaryKey(String key) {logger.debug("finding service by primary key");try {return getJdbcTemplate().query("SELECT serviceid,contenttype,templatetext FROM table where serviceid='"+key+"'",new RowMapper() {public Object mapRow(ResultSet rs, int rowNum) throws SQLException {String serviceid = rs.getString(1);String contenttype = rs.getString(2);String templatetext = lobHandler.getClobAsString(rs, 3);return new ServConTempBean(serviceid, contenttype, templatetext);}});} catch (RuntimeException re) {logger.warn("finding service by primary key failed", re);throw re;}} /** * 根据业务主键更新信息 * @param key * @param params * @param types * @return */public void updateContentByPrimaryKey(final String key,final String templatetext) {logger.debug("update service content by content template primary key");try {getJdbcTemplate().execute( "update table set templatetext=? where serviceid=?",new AbstractLobCreatingPreparedStatementCallback(this.lobHandler) {protected void setValues(PreparedStatement ps,LobCreator lobCreator) throws SQLException {lobCreator.setClobAsString(ps, 1, templatetext);ps.setString(2, key);}});} catch (RuntimeException re) {logger.warn("update service by service primary key failed", re);throw re;} }
