Java Web以输入输出流实现读取数据库图片

在web开发中，读取显示图片非常常见，实现方式也有很多，下面介绍一种以流的形式实现读取数据库图片。java环境：eclipse，数据库：MySQL。
其他过程忽略，只写Servlet和jsp代码。

Servlet写法

          public String imgAddr;
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        request.setCharacterEncoding("UTF-8");
          response.setCharacterEncoding("UTF-8");
          response.setContentType("text/html;charset=UTF-8");

          HttpSession session = request.getSession();
          String op = request.getParameter("op");

          switch (op) {
            case "showimg":
                       imgRead(request, response,imgAddr);
                       break;
        default:
            break;
        }
  }
    private void imgRead(HttpServletRequest request, HttpServletResponse response, String imgAddr) throws ServletException, IOException {
            // 本地文件路径
            String filePath = "E:" + File.separator + "Users" + File.separator + "Yohua " + File.separator + "weixinapp "
                    + File.separator + "Medical_master" + File.separator + imgAddr;
            File file = new File(filePath);
            // 获取输出流
            OutputStream outputStream = response.getOutputStream();
            FileInputStream fileInputStream = new FileInputStream(file);
            // 读数据
            byte[] data = new byte[fileInputStream.available()];
            fileInputStream.read(data);
            fileInputStream.close();
            // 回写
            response.setContentType(JPG);
            outputStream.write(data);
            outputStream.flush();
            outputStream.close();
        }

JSP代码

<body>
<img alt="showImage" src="AdminServlet?op=showimg">
</body>

↶ 返回首页