在这篇文章里介绍用JdbcTemplate进行数据库插入操作,包括对blob或clob字段的插入
还有对blob字段的取出操作。
1.使用JdbcTemplate往数据库里插入数据,其中包含blob字段。
- public boolean doSubmitWeekly(final WeeklyVO weeklyVO)
- throws DataAccessException {
- StringBuffer sql = new StringBuffer();
- sql.append("INSERT INTO WEEKLY_INFO_T T (T.F_START_TIME, ");
- sql.append(" T.F_END_TIME, ");
- sql.append(" T.F_DATE, ");
- sql.append(" T.F_OWNER, ");
- sql.append(" T.F_ANNEX_NAME, ");
- sql.append(" T.F_ANNEX) ");
- sql.append(" VALUES (TO_DATE (?, 'yyyy-mm-dd'), ");
- sql.append(" TO_DATE (?, 'yyyy-mm-dd'), ");
- sql.append(" TO_DATE (to_char(sysdate,'yyyy-mm-dd'), 'yyyy-mm-dd'), ");
- sql.append(" ?, ");
- sql.append(" ?, ");
- sql.append(" ?) ");//blob字段
- Boolean flag = new Boolean(false);
- try {
- flag = (Boolean) this.getJdbcTemplate().execute(sql.toString(),
- new MyPreparedStatementCallback(weeklyVO));
- } catch (Exception e) {
- e.printStackTrace();
- }
- return flag.booleanValue();
- }
MyPreparedStatementCallback类的实现
- /**
- * 上传附件回调操作类
- */
- private class MyPreparedStatementCallback implements
- PreparedStatementCallback {
- private WeeklyVO weeklyVO;
- public MyPreparedStatementCallback(WeeklyVO weeklyVO) {
- this.weeklyVO = weeklyVO;
- }
- public Object doInPreparedStatement(PreparedStatement pstm)
- throws SQLException,
- org.springframework.dao.DataAccessException {
- pstm.setObject(1, this.weeklyVO.getStartTime());
- pstm.setObject(2, this.weeklyVO.getEndTime());
- pstm.setObject(3, this.weeklyVO.getOwner());
- pstm.setObject(4, this.weeklyVO.getAnnexName());
- try {
- // 操作Blob ---这里WeeklyVO类的annex属性是File类型
- pstm.setBinaryStream(5, new FileInputStream(this.weeklyVO
- .getAnnex()), (int) (this.weeklyVO.getAnnex()).length());
- // 操作Clob
- /**
- pstm.setCharacterStream(5, new FileReader(this.weeklyVO
- .getAnnex()), (int) (this.weeklyVO.getAnnex()).length());
- */
- } catch (FileNotFoundException e) {
- e.printStackTrace();
- return new Boolean(false);
- }
- try {
- pstm.execute();
- return new Boolean(true);
- } catch (Exception e) {
- e.printStackTrace();
- return new Boolean(false);
- }
- }
- }
2.使用JdbcTemplate读取数据库中的blob字段信息(把blob内容写到临时目录)
- public Map doSelectWeekly(String weeklyId) throws DataAccessException {
- String sql = "select t.f_annex_name,t.f_annex from weekly_info_t t"
- + " where t.f_weekly_id = " + weeklyId;
- Map map = new HashMap();
- map = (Map) this.getJdbcTemplate().execute(sql,
- new CallableStatementCallback() {
- public Object doInCallableStatement(CallableStatement stmt)
- throws SQLException,
- org.springframework.dao.DataAccessException {
- ResultSet rs = stmt.executeQuery();
- Map map = new HashMap();
- InputStream inputStream = null;
- String name = "";
- String path = System.getProperty("java.io.tmpdir")
- + "/";
- File temp = new File(path);
- if (!temp.exists()) {
- temp.mkdir();
- }
- temp = null;
- while (rs.next()) {
- inputStream = rs.getBinaryStream("f_annex");// 读取blob
- //Reader fileReader = rs.getCharacterStream("f_annex");// 读取clob
- name = rs.getString("f_annex_name");
- path += name;
- File fileOutput = new File(path);
- FileOutputStream fo;
- try {
- fo = new FileOutputStream(fileOutput);
- int readed;
- // 将附件写到临时目录里
- while ((readed = inputStream.read()) != -1) {
- fo.write(readed);
- }
- fo.close();
- } catch (FileNotFoundException e) {
- e.printStackTrace();
- } catch (IOException e) {
- e.printStackTrace();
- }
- }
- map.put("annexName", name);
- map.put("filePath", path);
- return map;//返回文件名称和文件所在路径,供页面下载用。
- }
- });
- return map;
- }
附:下载blob内容代码片段(先把blob内容写到临时目录在从临时目录下载)
- Map map = weeklyServise.doSelectWeekly("52");//参数为附件ID
- String annexName = (String) map.get("annexName");
- String path = (String) map.get("filePath");
- BufferedInputStream bis = null;
- BufferedOutputStream bos = null;
- OutputStream fos = null;
- InputStream fis = null;
- String filepath = path;
- System.out.println("文件路径" + filepath);
- java.io.File uploadFile = new java.io.File(filepath);
- //从低级流构造成高级流
- fis = new FileInputStream(uploadFile);
- bis = new BufferedInputStream(fis);
- fos = response.getOutputStream();
- bos = new BufferedOutputStream(fos);
- //设置下载文件名
- response.setHeader("Content-disposition", "attachment;filename="
- + URLEncoder.encode(annexName, "utf-8"));
- int bytesRead = 0;
- byte[] buffer = new byte[4096];
- while ((bytesRead = bis.read(buffer, 0, 4096)) != -1) {
- bos.write(buffer, 0, bytesRead);//开始下载数据
- }
- bos.flush();
- fis.close();
- bis.close();
- fos.close();
- bos.close();
- java.io.File temp = new java.io.File(System.getProperty("java.io.tmpdir")+"/");
- if(temp.isDirectory()){
- FileUtils.deleteDirectory(temp);//删除临时文件夹
- }
- return null;