SpringMVC combines with Jcrop to achieve image clipping

The example of this paper is to share the specific code of SpringMVC and Jcrop to realize picture clipping for your reference. The specific content is as follows

1. jsp page:

<form name="form" action="<%=request.getContextPath()%>/UploadDemo/uploadHeadImage" class="form-horizontal" 
   method="post" enctype="multipart/form-data"> 
  <div class="modal-body text-center"> 
    <div class="zxx_main_con"> 
      <div class="zxx_test_list"> 
        <input class="photo-file" type="file" name="imgFile" id="fcupload" onchange="readURL(this);"/> 
        <img alt="" src="" id="cutimg"/> 
        <input type="hidden" id="x" name="x"/> 
        <input type="hidden" id="y" name="y"/> 
        <input type="hidden" id="w" name="w"/> 
        <input type="hidden" id="h" name="h"/> 
      </div> 
    </div> 
  </div> 
   
  <div class="modal-footer"> 
    <button id="submit" onclick=""> upload </button> 
  </div> 
</form> 

2. jcrop component references:

<link rel="stylesheet" href="<c:url value="/resources/uploadPlugin/css/jquery.Jcrop.css"/>" type="text/css"></link> 
  <script type="text/javascript" src="<c:url value="/resources/uploadPlugin/scripts/jquery-1.8.3.js"/>"></script> 
  <script type="text/javascript" src="<c:url value="/resources/uploadPlugin/scripts/jquery.Jcrop.js"/>"></script> 

3. Usage of jcrop

<script type="text/javascript"> 
   // define 1 A global api It is more flexible to operate in this way  
    var api = null; 
    function readURL(input) { 
      if (input.files && input.files[0]) { 
        var reader = new FileReader(); 
        reader.readAsDataURL(input.files[0]); 
        reader.onload = function (e) { 
          $('#cutimg').removeAttr('src'); 
          $('#cutimg').attr('src', e.target.result); 
          api = $.Jcrop('#cutimg', { 
            setSelect: [ 20, 20, 200, 200 ], 
            aspectRatio: 1, 
            onSelect: updateCoords 
          }); 
        }; 
        if (api != undefined) { 
          api.destroy(); 
        } 
      } 
      function updateCoords(obj) { 
        $("#x").val(obj.x); 
        $("#y").val(obj.y); 
        $("#w").val(obj.w); 
        $("#h").val(obj.h); 
      }; 
    } 
  </script> 

4. Background code:

@RequestMapping(value = "/uploadHeadImage") 
  public String uploadHeadImage( 
      HttpServletRequest request, 
      @RequestParam(value = "x") String x, 
      @RequestParam(value = "y") String y, 
      @RequestParam(value = "h") String h, 
      @RequestParam(value = "w") String w, 
      @RequestParam(value = "imgFile") MultipartFile imageFile 
  ) throws Exception{ 
    System.out.println("==========Start============="); 
    String realPath = request.getSession().getServletContext().getRealPath("/"); 
    String resourcePath = "resources/uploadImages/"; 
    if(imageFile!=null){ 
      if(FileUploadUtil.allowUpload(imageFile.getContentType())){ 
        String fileName = FileUploadUtil.rename(imageFile.getOriginalFilename()); 
        int end = fileName.lastIndexOf("."); 
        String saveName = fileName.substring(0,end); 
        File dir = new File(realPath + resourcePath); 
        if(!dir.exists()){ 
          dir.mkdirs(); 
        } 
        File file = new File(dir,saveName+"_src.jpg"); 
        imageFile.transferTo(file); 
        String srcImagePath = realPath + resourcePath + saveName; 
        int imageX = Integer.parseInt(x); 
        int imageY = Integer.parseInt(y); 
        int imageH = Integer.parseInt(h); 
        int imageW = Integer.parseInt(w); 
        // This is where the interception begins  
        System.out.println("==========imageCutStart============="); 
        ImageCut.imgCut(srcImagePath,imageX,imageY,imageW,imageH); 
        System.out.println("==========imageCutEnd============="); 
      } 
    } 
    return "user/uploadImg/test"; 
  } 

5. ImageCut.java tools:

/** 
   *  Capture images  
   * @param srcImageFile  Original picture address  
   * @param x   At the time of capture x coordinates  
   * @param y   At the time of capture y coordinates  
   * @param desWidth   Width of intercept  
   * @param desHeight   Intercept height  
   */ 
  public static void imgCut(String srcImageFile, int x, int y, int desWidth, 
               int desHeight) { 
    try { 
      Image img; 
      ImageFilter cropFilter; 
      BufferedImage bi = ImageIO.read(new File(srcImageFile+"_src.jpg")); 
      int srcWidth = bi.getWidth(); 
      int srcHeight = bi.getHeight(); 
      if (srcWidth >= desWidth && srcHeight >= desHeight) { 
        Image image = bi.getScaledInstance(srcWidth, srcHeight,Image.SCALE_DEFAULT); 
        cropFilter = new CropImageFilter(x, y, desWidth, desHeight); 
        img = Toolkit.getDefaultToolkit().createImage( 
            new FilteredImageSource(image.getSource(), cropFilter)); 
        BufferedImage tag = new BufferedImage(desWidth, desHeight, 
            BufferedImage.TYPE_INT_RGB); 
        Graphics g = tag.getGraphics(); 
        g.drawImage(img, 0, 0, null); 
        g.dispose(); 
        // The output file  
        ImageIO.write(tag, "JPEG", new File(srcImageFile+"_cut.jpg")); 
      } 
    } catch (Exception e) { 
      e.printStackTrace(); 
    } 
  } 

6. Two ways of using jcrop:

1.

jQuery('#cropbox').Jcrop({
         onChange: showCoords,
         onSelect: showCoords
      });

2,

var api = $.Jcrop('#cropbox',{
         onChange: showPreview,
         onSelect: showPreview,
         aspectRatio: 1
      });