Spring Boot 利用WebUploader进行文件上传功能

(function( factory ) {
  if ( !window.jQuery ) {
    alert('jQuery is required.')
  }
  jQuery(function() {
    factory.call( null, jQuery );
  });
})
(function( $ ) {
// -----------------------------------------------------
// ------------ START ----------------------------------
// -----------------------------------------------------
// ---------------------------------
// --------- Uploader -------------
// ---------------------------------
  var Uploader = (function() {
    // -------setting-------
    // 如果使用原始大小，超大的图片可能会出现 Croper UI 卡顿，所以这里建议先缩小后再crop.
    var FRAME_WIDTH = 1600;
    var _ = WebUploader;
    var Uploader = _.Uploader;
    var uploaderContainer = $('.uploader-container');
    var uploader, file;
    if ( !Uploader.support() ) {
      alert( 'Web Uploader 不支持您的浏览器！');
      throw new Error( 'WebUploader does not support the browser you are using.' );
    }
    // hook,
    // 在文件开始上传前进行裁剪。
    Uploader.register({
      'before-send-file': 'cropImage'
    }, {
      cropImage: function( file ) {
        var data = file._cropData,
          image, deferred;
        file = this.request( 'get-file', file );
        deferred = _.Deferred();
        image = new _.Lib.Image();
        deferred.always(function() {
          image.destroy();
          image = null;
        });
        image.once( 'error', deferred.reject );
        image.once( 'load', function() {
          image.crop( data.x, data.y, data.width, data.height, data.scale );
        });
        image.once( 'complete', function() {
          var blob, size;
          // 移动端 UC / qq 浏览器的无图模式下
          // ctx.getImageData 处理大图的时候会报 Exception
          // INDEX_SIZE_ERR: DOM Exception 1
          try {
            blob = image.getAsBlob();
            size = file.size;
            file.source = blob;
            file.size = blob.size;
            file.trigger( 'resize', blob.size, size );
            deferred.resolve();
          } catch ( e ) {
            console.log( e );
            // 出错了直接继续，让其上传原始图片
            deferred.resolve();
          }
        });
        file._info && image.info( file._info );
        file._meta && image.meta( file._meta );
        image.loadFromBlob( file.source );
        return deferred.promise();
      }
    });
    return {
      init: function( selectCb ) {
        uploader = new Uploader({
          pick: {
            id: '#filePicker',
            multiple: false
          },
          // 设置用什么方式去生成缩略图。
          thumb: {
            quality: 70,
            // 不允许放大
            allowMagnify: false,
            // 是否采用裁剪模式。如果采用这样可以避免空白内容。
            crop: false
          },
          // 禁掉分块传输，默认是开起的。
          chunked: false,
          // 禁掉上传前压缩功能，因为会手动裁剪。
          compress: false,
          // fileSingleSizeLimit: 2 * 1024 * 1024,
          server: 'StudentImgFileUpload',
          swf: $.trim($("#BASE_URL").val()) + '/static/webuploader/Uploader.swf',
          fileNumLimit: 1,
          // 只允许选择图片文件。
          accept: {
            title: 'Images',
            // extensions: 'gif,jpg,jpeg,bmp,png',
            // mimeTypes: 'image/*'
            extensions: 'jpg,jpeg,png',
            //解决WebUploader chrome 点击上传文件选择框会延迟几秒才会显示 反应很慢
            mimeTypes: 'image/jpg,image/jpeg,image/png'  //修改这行
          }
          //formData: {"Authorization": localStorage.token}, //额外参数传递，可以没有
          // chunked: true, //分片
          // chunkSize: 10 * 1024 * 1024, //分片大小指定
          // threads:1, //线程数量
          // disableGlobalDnd: true //禁用拖拽
          // onError: function() {
          //   var args = [].slice.call(arguments, 0);
          //   alert(args.join('\n'));
          // }
        });
        uploader.on('fileQueued', function( _file ) {
          file = _file;
          uploader.makeThumb( file, function( error, src ) {
            if ( error ) {
              alert('不能预览');
              return;
            }
            selectCb( src );
          }, FRAME_WIDTH, 1 );  // 注意这里的 height 值是 1，被当成了 100% 使用。
        });
        /**
         * 验证文件格式以及文件大小
         */
        uploader.on("error", function (type) {
          if (type == "Q_TYPE_DENIED") {
            showInfo("请上传JPG、JEPG、PNG、格式文件");
          }
        });
        // 文件上传成功，给item添加成功class, 用样式标记上传成功。
        uploader.on( 'uploadSuccess', function( file ) {
          showInfo("上传成功");
        });
        // 文件上传失败，显示上传出错。
        uploader.on( 'uploadError', function( file ) {
          showInfo("上传失败");
        });
      },
      crop: function( data ) {
        var scale = Croper.getImageSize().width / file._info.width;
        data.scale = scale;
        file._cropData = {
          x: data.x1,
          y: data.y1,
          width: data.width,
          height: data.height,
          scale: data.scale
        };
      },
      upload: function() {
        uploader.upload();
      }
    }
  })();
// ---------------------------------
// --------- Crpper ---------------
// ---------------------------------
  var Croper = (function() {
    var container = $('.cropper-wraper');
    var $image = container.find('.img-container img');
    var btn = $('.upload-btn');
    var isBase64Supported, callback;
    $image.cropper({
      aspectRatio: 4 / 4,
      preview: ".img-preview",
      done: function(data) {
        // console.log(data);
      }
    });
    function srcWrap( src, cb ) {
      // we need to check this at the first time.
      if (typeof isBase64Supported === 'undefined') {
        (function() {
          var data = new Image();
          var support = true;
          data.onload = data.onerror = function() {
            if( this.width != 1 || this.height != 1 ) {
              support = false;
            }
          }
          data.src = src;
          isBase64Supported = support;
        })();
      }
      if ( isBase64Supported ) {
        cb( src );
      } else {
        // otherwise we need server support.
        // convert base64 to a file.
        // $.ajax('', {
        //   method: 'POST',
        //   data: src,
        //   dataType:'json'
        // }).done(function( response ) {
        //   if (response.result) {
        //     cb( response.result );
        //   } else {
        //     alert("预览出错");
        //   }
        // });
      }
    }
    btn.on('click', function() {
      callback && callback($image.cropper("getData"));
      return false;
    });
    return {
      setSource: function( src ) {
        // 处理 base64 不支持的情况。
        // 一般出现在 ie6-ie8
        srcWrap( src, function( src ) {
          $image.cropper("setImgSrc", src);
        });
        container.removeClass('webuploader-element-invisible');
        return this;
      },
      getImageSize: function() {
        var img = $image.get(0);
        return {
          width: img.naturalWidth,
          height: img.naturalHeight
        }
      },
      setCallback: function( cb ) {
        callback = cb;
        return this;
      },
      disable: function() {
        $image.cropper("disable");
        return this;
      },
      enable: function() {
        $image.cropper("enable");
        return this;
      }
    }
  })();
// ------------------------------
// -----------logic--------------
// ------------------------------
  var container = $('.uploader-container');
  Uploader.init(function( src ) {
    Croper.setSource( src );
    // 隐藏选择按钮。
    container.addClass('webuploader-element-invisible');
    // 当用户选择上传的时候，开始上传。
    Croper.setCallback(function( data ) {
      Uploader.crop(data);
      Uploader.upload();
    });
  });
// -----------------------------------------------------
// ------------ END ------------------------------------
// -----------------------------------------------------
});

 @RequestMapping(value="/student/StudentImgFileUpload", method=RequestMethod.POST)
  @ResponseBody
  String studentImgFileUpload(@RequestParam MultipartFile file, HttpServletRequest request){
    logger.info("学生头像上传....")
    //获取文件名
    String originalFilename = file.getOriginalFilename()
    logger.info("上传文件名：" + originalFilename)
    String realPath = request.getServletContext().getRealPath("/public/student/")
    String uploadFileName = System.currentTimeMillis()+"_"+ originalFilename
    logger.info("获取上传路径：" + realPath + ", 上传的真实文件名：" + uploadFileName)
    boolean flag = true

    //合并文件
    RandomAccessFile raFile = null
    BufferedInputStream inputStream = null
    try{
      File dirFile = new File(realPath, uploadFileName)
      //以读写的方式打开目标文件
      raFile = new RandomAccessFile(dirFile, "rw")
      raFile.seek(raFile.length())
      inputStream = new BufferedInputStream(file.getInputStream())
      byte[] buf = new byte[1024]
      int length = 0
      while ((length = inputStream.read(buf)) != -1) {
        raFile.write(buf, 0, length)
      }
    }catch(Exception e){
      flag = false
      logger.info("上传出错:" + e.getMessage())
      throw new IOException(e.getMessage())
    }finally{
      try {
        if (inputStream != null) {
          inputStream.close()
        }
        if (raFile != null) {
          raFile.close()
        }
      }catch(Exception e){
        flag = false
        logger.info("上传出错:" + e.getMessage())
        throw new IOException(e.getMessage())
      }
    }
  }