[大数据]JDBC操作blob类型文件(图片、视频)

添加blob类型的数据

    //插入blob类型的数据
    public void testInsert() throws Exception {
        Connection conn = JDBCutils.getConnection();
        String sql="insert into testblob (photo) values (?)";
        PreparedStatement ps = conn.prepareStatement(sql);
        //文件数据需要先创建流对象
        FileInputStream is = new FileInputStream(new File("D:\\JDBC学习\\jdbc_01\\src\\tt.jpg"));
        ps.setObject(1,is);
        ps.execute();
        JDBCutils.closeResource(ps,conn);
        is.close();
    }

删除、修改等操作与插入操作相似

从数据库中下载blob类型数据

//下载blob类型的数据
    public  void  testQuery() {
        Connection conn = null;
        PreparedStatement ps = null;
        ResultSet rs = null;
        InputStream is =null;
        FileOutputStream fos=null;
        try {
            conn = JDBCutils.getConnection();
            String sql="select photo from testblob";
            ps = conn.prepareStatement(sql);
            rs = ps.executeQuery();
            if(rs.next()){
                Blob photo = rs.getBlob("photo");
                is = photo.getBinaryStream();
               fos=new FileOutputStream("t1.jpg");
              byte[] bytes=new byte[1024];
              int len=0;
              while ((len=is.read(bytes))!=-1){
                  fos.write(bytes,0,len);
              }

            }
        } catch (Exception e) {
            e.printStackTrace();

        } finally {

            try {
                if(is!=null){
                    is.close();
                }
                if(fos!=null){
                    fos.close();
                }

            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        JDBCutils.closeResource(ps,conn,rs);


    }