文件输入到Spring Boot应用程序

Question

I have a text file containing phone numbers which is new line seperated, I want to pass this file to the spring boot application, and copy the content of the file into the list.

@RequestMapping(value = "/FileUpload", method = RequestMethod.POST, consumes = MediaType.APPLICATION_JSON_VALUE, produces = MediaType.APPLICATION_JSON_UTF8_VALUE)
public ResponseEntity<String> FileUpload(@RequestParam("file") MultipartFile file,
                                        HttpServletRequest request, 
                                        HttpServletResponse response) {

  ....
}

thanks :)

Answer 1

Here is a complete example for reading a text file and returning it's content as strping comma sparated numbers :

@RequestMapping(value = "/FileUpload", method = RequestMethod.POST, consumes = MediaType.APPLICATION_JSON_VALUE, produces = MediaType.APPLICATION_JSON_UTF8_VALUE)
public ResponseEntity<String> FileUpload(@RequestParam("file") MultipartFile file,  HttpServletRequest request, HttpServletResponse response) throws IOException  {
     List<String> numbers = new ArrayList<String>();
     InputStream inputStream = file.getInputStream(); 
     BufferedReader bufferReader =   new BufferedReader(new InputStreamReader(inputStream));
     String numberLine;
     while ((numberLine = bufferReader.readLine()) != null) {
        numbers.add(numberLine);
     }
     bufferReader.close();
     /* pint all numbers */
     numbers.forEach(System.out::println):
     String result = String.join(",", numbers);
     return new ResponseEntity<String>(result, HttpStatus.OK);
}

Answer 2

you should write a function to create a list from a MultipartFile using a BufferedReader to get every number line by line. Here's what you can do with a BufferedReader:

String line;
List<String> numberList = new ArrayList<>()
val bufferedReader = BufferedReader(new FileReader(myFile));
do {
    line = bufferedReader.readLine();
    if(line != null) {
        numbersList.add(line);
    }
} while (line != null)
bufferedReader.close()

Maybe you'll have to write some additional code to fit with your needs, but it should do the job. Try this and tell me if it works, I didn't test with MultipartFile.