我无法读取 java 代码中的文件内容，通过 extjs 代码传递给 java spring 控制器

Question

   // Here's my extjs code
    Ext.define('ArticulationAgreement.view.Filechooser',{
        extend : 'Ext.form.Panel',
        alias : 'widget.filechooser',
        mixins: ['Deft.mixin.Injectable', 'Deft.mixin.Controllable'],
        //controller : ['ArticulationAgreement.controller.FilechooserController'],
        width : 1500,
        height : 300,
        bodyPadding: '10 10 0',
        frame: true,

        initComponent : function(){
            var me = this;
            Ext.apply(me, {


                title : 'Add the CSV Files',
                defaults:
                            {
                                anchor: '30%',
                                allowBlank: false,
                                msgTarget: 'side',
                                labelWidth: 100
                            },
                items : [
                        {
                            xtype: 'filefield',
                            id: 'form-file',
                            emptyText: 'Select a File',
                            //maxLength : '30',
                            fieldLabel: 'File Selected',
                            name: 'fpath',
                            buttonText: 'upload file'

                        },

                    {
                            text : 'Save File',
                            xtype : 'button',
                            width: 75,
                            itemId : 'save',
                            layout : 'hbox',
                            anchor : '5%',
                            handler : function(){
                            //console.log(this.up('form').down('textfield[name=file-path]').value);
                            var form = this.up('form').getForm();
                            if(form.isValid()){
                                form.submit({
                                url : 'http://localhost:8080/ssp/api/upload.action',
                                waitMsg: 'Uploading your file',
                                success: function(fp, o) {
                                    Ext.Msg.alert('Success', 'Your file has been uploaded.'+fp.responseText);
                                }
                                });
                            }
                            }
                    },
                    {
                        text : 'Reset',
                        xtype : 'button',
                        width : 75,
                        layout : 'hbox',
                        anchor : '5%',
                        handler : function(){
                            this.up('form').getForm().reset();
                        }
                    }
                ]
            });
            return me.callParent(arguments);
        }
    });

//这是我的spring控制器代码

@RequestMapping(method = RequestMethod.POST)
 public 
   ResponseEntity<String> uploadFile(FileUploadBean uploadItem, BindingResult result) throws Exception {
        System.out.println("QUERY TO UPLOAD FILE");
        try {

                MultipartFile file = uploadItem.getFile();
                String fileName = null;
                InputStream inputStream = null;
                OutputStream outputStream = null;
              //Exception on next line:
               System.out.println("Test upload: " + uploadItem.getFile().getOriginalFilename());

            //rest of the code

            return null;
        }

//我在 java 控制器中遇到异常，它在 extjs 代码中给出了响应—— //Uncaught Ext.JSON.decode(): 你试图解码一个无效的 JSON 字符串： //如果可能请帮助我，在此先感谢。

Answer 1

         //Extjs Code
          {
                    xtype: 'filefield',
                    emptyText: 'Select a File',
                    //maxLength : '30',
                    fieldLabel: 'File Selected',
                    name: 'file',//change in only this line was needed
                    buttonText: 'Choose File'
           }

           //Spring Controller Code
            @RequestMapping(method = RequestMethod.POST)
            public @ResponseBody String uploadFile(FileUploadBean uploadItem, BindingResult result) throws Exception {
    System.out.println("QUERY TO UPLOAD FILE");
    try {

            CommonsMultipartFile file = uploadItem.getFile();//changed line
            String fileName = null;
            InputStream inputStream = null;
            OutputStream outputStream = null;

           System.out.println("Test upload: " + uploadItem.getFile().getOriginalFilename());

        //rest of the code
        }
        return null;
    }

我无法读取 java 代码中的文件内容，通过 extjs 代码传递给 java spring 控制器

I am not been able to read the file contents in java code, passed through extjs code to java spring controller

spring-mvc

extjs4.1