如何使用spring和hibernate从mysql中获取图像列表

Question

我以字节格式将图像存储在 mysql 数据库表中。当我从数据库中检索该图像时，我得到了这样的结果。

所以dispatcher-servlet.xml如下

<beans:bean id="multipartResolver"
        class="org.springframework.web.multipart.commons.CommonsMultipartResolver">

         <!-- setting maximum upload size -->
        <beans:property name="maxUploadSize" value="100000" />

    </beans:bean>

pom.xml

<!-- Apache Commons FileUpload --> 
<dependency>
    <groupId>commons-fileupload</groupId>
    <artifactId>commons-fileupload</artifactId>
    <version>1.3.1</version>
</dependency>

<!-- Apache Commons IO --> 
<dependency>
    <groupId>commons-io</groupId>
    <artifactId>commons-io</artifactId>
    <version>2.4</version>
</dependency>

driversList.jsp

<div style="color: teal; font-size: 20px">List Of Drivers</div>
            <c:if test="${!empty listDrivers}">
                <table border="1" bgcolor="black" width="600px">
                    <tr
                        style="background-color: teal; color: white; text-align: center;"
                        height="40px">
                        <th width="60">Name</th>
                        <th width="80">License Number</th>
                        <!--  <th width="80">Password</th> -->
                        <th width="80">Phone</th>

                        <th width="80">Password</th>
                        <th width="80">Address</th>
                        <th width="80">Photo</th>

                    </tr>
                    <c:forEach items="${listDrivers}" var="driver">
                        <tr
                            style="background-color: white; color: black; text-align: center;"
                            height="30px">

                            <td>${driver.name}</td>
                            <td>${driver.license}</td>
                            <td>${driver.number}</td>

                            <td>${driver.password}</td>
                            <td>${driver.address}</td>
                            <td><img src="/momcab1/myImage/imageDisplay?id=${driver.id}"/></td>

                        </tr>
                    </c:forEach>
                </table>
            </c:if>
            <!-- Content data end -->
            <br> <br> <br> <br> <br> <br> <br>
            <br> <br> <br>
        </div>

DriverController.java

@RequestMapping(value = "/DriversList", method = RequestMethod.GET)
    public String listUsers(Model model,HttpServletRequest req,HttpServletResponse res) {

        HttpSession session =req.getSession();
         if(session.getAttribute("emailId")==null)
         {
             return "redirect:/login";
         }
         System.out.println("MY NAME IS GO PINK");
        model.addAttribute("listDrivers", this.driverService.listDrivers());
        return "driversList";
    }

ImageController.java

@Controller
@RequestMapping("/myImage")
public class ImageController {

    @Value("${login_session_token_timeout_mnts}")
    private String loginSessionTokenTimeoutMnts;

    private DriverService driverService;

    @Autowired(required = true)
    @Qualifier(value = "driverService")
    public void setDriverService(DriverService ds) {
        this.driverService = ds;
    }

    @RequestMapping(value = "/imageDisplay", method = RequestMethod.GET)
      public void showImage(@RequestParam("id") Integer id, HttpServletResponse response,HttpServletRequest request) 
              throws ServletException, IOException{


        Driver item = driverService.getDriverById(id);       
        response.setContentType("image/jpeg, image/jpg, image/png, image/gif");
        response.getOutputStream().write(item.getBlobImg());


        response.getOutputStream().close();
    }

}

驱动程序.java

@Column(name = "photo")
    private byte[] blobImg;

所以在这里，当一个人点击“驱动程序列表”时，请求映射会转到DriverController.java 的"/DriversList" 但在我的driversList.jsp 中，有一个图像要从mysql 数据库表中显示。但是当页面加载时，它甚至不会进入"<img src>" 中给出的控制器请求映射 它显示一个“十字标记”，如下所示。对此的任何帮助将不胜感激。

谢谢你

我尝试了enter link description here中给出的代码

Answer 1

在Spring MVC: How to return image in @ResponseBody? 之前已经回答了这个问题。您可能缺少编码或类似的东西是最有可能的候选人。但有什么关系，只要使用其他人都在使用的、人人都知道的方法就行了。

举个例子

public class HELLOWORLD {


  class FooEntity {

    // TODO - ids and other stuff

    @Lob @Basic(fetch = FetchType.LAZY)
    private byte[] imageBytes;

    public byte[] getImageBytes() {
      return imageBytes;
    }
  }

  interface FooService {
    public FooEntity get(int id);
  }


  public static byte[] bufferedImageToByteArray(BufferedImage img) throws IOException
  {
      ByteArrayOutputStream baos = new ByteArrayOutputStream();
      ImageIO.write(img, "png", baos ); // I think this doesn't matter, I have jpg here
      return baos.toByteArray();
  }

  FooService fooService;

  @RequestMapping(value = "/foo/image/{id}")
  @ResponseBody
  public byte[] GetUserImageTiny(Model model, @PathVariable Integer id) throws IOException
  {   
      FooEntity fooEntity = fooService.get(id);
      byte[] imageInByte = fooEntity.getImageBytes();
      // you may be able to just go:
      // return imageInByte;
      // but I actually create the image:
      InputStream in = new ByteArrayInputStream(imageInByte);
      BufferedImage bImageFromConvert = ImageIO.read(in); // you could then debug here, write the image to a file to test if it's all good.
      // I sometimes resize the image too which I would do here
      // otherwise just return the image
      return bufferedImageToByteArray(bImageFromConvert);
  }

}

Answer 2

我得到了答案…………

是我在数据库中添加图片错误，所以我修改了添加图片到数据库的代码

@RequestMapping(value = "/Drivers/add", method = RequestMethod.POST)
    public String addUser(@ModelAttribute("driver") Driver driver,BindingResult result,@RequestParam("blobImg") MultipartFile blobImg) {

        if (driver.getId() == 0) {
            // new user, add to DB

            System.out.println("Name:" + driver.getName());

            System.out.println("File:" + blobImg.getSize());
            System.out.println("ContentType:" + blobImg.getContentType());

                    try {
                        driver.setBlobImg(blobImg.getBytes());
                    } catch (IOException e) {
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                    }

                 }


                this.driverService.addDriver(driver);





        return "redirect:/Drivers";

    }

然后我通过这段代码获取

@RequestMapping(value = "/imageDisplay/{id}", method = RequestMethod.GET)
      public String showImage(@PathVariable("id") int id, HttpServletResponse response,HttpServletRequest request) 
              throws ServletException, IOException{
System.out.println("Image isn't coming");
System.out.println("Id is"+id);
        Driver item = driverService.getDriverById(id);    
                 try {
        response.setContentType("image/jpeg, image/jpg, image/png, image/gif");
        response.getOutputStream().write(item.getBlobImg());


        response.getOutputStream().close();
                 }
                 catch(Exception e) {
                     e.printStackTrace();
                 }
       return "driversList";
    }