[SpringBoot2.4.3] ファイルアップロード – ソフトウェアエンジニアの技術ブログ：Software engineer tech blog

htmlファイル
src/main/resources/public/file-upload.html

<!DOCTYPE html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<meta name="viewport" content="width=device-width, initial-scale=1.0">
	<title>File Upload</title>
	<link href="https://cdn.jsdelivr.net/npm/bootstrap@5.0.0-beta1/dist/css/bootstrap.min.css" rel="stylesheet" integrity="sha384-giJF6kkoqNQ00vy+HMDP7azOuL0xtbfIcaT9wjKHr8RbDVddVHyTfAAsrekwKmP1" crossorigin="anonymous">
	<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/5.14.0/css/all.min.css">
</head>
<body>
<div class="">
	<form id="form" enctype="multipart/form-data">
		<p><input type="file" name="file"></p>
		<p><input type="button" id="upload" value="upload"></p>
	</form>
	<span id="result" style="padding:3px"></span>

</div>
<script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.16.1/umd/popper.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/twitter-bootstrap/5.0.0-alpha1/js/bootstrap.min.js"></script>
<script
  src="https://code.jquery.com/jquery-3.5.1.js"
  integrity="sha256-QWo7LDvxbWT2tbbQ97B53yJnYU3WhH/C8ycbRAkjPDc="
  crossorigin="anonymous"></script>
<script>
$(function(){
	$('#upload').click(function(){
		var formData = new FormData(
			$('#form').get()[0]
		);
		$.ajax({
			url:'/upload',
			method:'post',
			data:formData,
			processData:false,
			contentType:false,
			cache: false
		}).done(function(data,status,jqxhr){
			$('#result').text('結果: 成功');
		}).fail(function(data, status, jqxhr){
			$('#result').text('結果: 失敗');
		});
	});
});
</script>
</body>
</html>

Controller

package com.example.demo;

import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.FileOutputStream;
import java.io.IOException;

import javax.servlet.http.HttpServletResponse;

import org.springframework.util.FileCopyUtils;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.multipart.MultipartFile;

@RestController
public class HelloController {
	
	@RequestMapping(value="/upload", method=RequestMethod.POST)
	public void handle(
			HttpServletResponse response,
			@RequestParam MultipartFile file
			) {
		if(file.isEmpty()) {
			response.setStatus(HttpServletResponse.SC_BAD_REQUEST);
			return;
		}
		try {
			BufferedInputStream in = new BufferedInputStream(file.getInputStream());
			BufferedOutputStream out = new BufferedOutputStream(
					new FileOutputStream(file.getOriginalFilename()));
		} catch (IOException e) {
			throw new RuntimeException("Error uploading file.", e);
		}
	}

publicに置くと、routingしなくて良いのか。。

ほう、こんなんなってるのか。。