java - MultipartException: Current request is not a multipart request

Question

I am trying to make a restful controller to upload files. I have seen this and made this controller:

@RestController
public class MaterialController {

    @RequestMapping(value="/upload", method= RequestMethod.POST)
    public String handleFileUpload(
            @RequestParam("file") MultipartFile file){
        String name = "test11";
        if (!file.isEmpty()) {
            try {
                byte[] bytes = file.getBytes();
                BufferedOutputStream stream =
                        new BufferedOutputStream(new FileOutputStream(new File(name + "-uploaded")));
                stream.write(bytes);
                stream.close();
                return "You successfully uploaded " + name + " into " + name + "-uploaded !";
            } catch (Exception e) {
                return "You failed to upload " + name + " => " + e.getMessage();
            }
        } else {
            return "You failed to upload " + name + " because the file was empty.";
        }
    }
}

and then i used postman to send a pdf:

But the server crashes with the error:

.MultipartException: Current request is not a multipart request

Again i have found this, and added a bean.xml file

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd">

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

Unfortunately, it still complains with the same error.

Answer 1

When you are using Postman for multipart request then don't specify a custom Content-Type in Header. So your Header tab in Postman should be empty. Postman will determine form-data boundary. In Body tab of Postman you should select form-data and select file type. You can find related discussion at https://github.com/postmanlabs/postman-app-support/issues/576