Problem with FileUpload - Null Value for Multipart File

Question

I am working on a Spring web application and need to implement a simple FileUpload for one of my pages.

The page for the JSP contains the following snippet of code which included an upload field for uploading the file.

<form:form commandName="editMemberInfoModelObj" method="post" enctype="multipart/form-data">
        <h1>Edit Member Information</h1>
        <table>
            //Other Form Input Fields ...
            <tr>
                <td>File</td>
                <td><input type="file" name="file"/></td>
            </tr>
            <tr>
                <td><input type="submit" value="Update Info"/></td>
            </tr>
        </table>
    </form:form>

The model for this JSP looks like the following

public class EditMerchandiserModel(){
        private MultipartFile file;

        //getters and setters for all the properties
}

The code in the controller that handles the file upload looks like the following

    if(model.getFile().isEmpty())  -->THROWING NULLPOINTER EXCEPTION HERE
    {
        MultipartFile file = model.getFile();
        String fileName = file.getOriginalFilename();
        String filePath = "/usr/local/" + fileName;
        FileOutputStream fos = new FileOutputStream(filePath);
         try 
             {

            fos.write(file.getBytes());
         } catch (IllegalStateException e) {
            System.out.println(e);

         }
         finally{
             fos.close();
         }
    }

I am unable to hit the inside code because it is reading in the file as a null value. Why is it not binding the value to the field?

Answer 1

看起来您的文件输入框的名称为“file”，而它应该绑定的属性名称为“photo”（至少您试图使用“getPhoto（）”来检索它.Spring很聪明，但它不是那么聪明。:)