Spring Boot file upload example
By：Roy.LiuLast updated：2019-08-11
This article shows you how to upload a file in Spring Boot web application.
Tools used :
- Spring Boot 1.4.3.RELEASE
- Spring 4.3.5.RELEASE
- Thymeleaf
- Maven
- Embedded Tomcat 8.5.6
1. Project Structure
A standard project structure.
2. Project Dependency
Spring boot dependencies, no need extra library for file upload.
pom.xml
<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0
http://maven.apache.org/maven-v4_0_0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.mkyong</groupId>
<artifactId>spring-boot-file-upload</artifactId>
<packaging>jar</packaging>
<version>1.0</version>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>1.4.3.RELEASE</version>
</parent>
<properties>
<java.version>1.8</java.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-thymeleaf</artifactId>
</dependency>
<!-- hot swapping, disable cache for template, enable live reload -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-devtools</artifactId>
<optional>true</optional>
</dependency>
</dependencies>
<build>
<plugins>
<!-- Package as an executable jar/war -->
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
</project>
3. File Upload Example
Spring boot file upload, zero configuration.
3.1 In the Controller, maps the uploaded file to MultipartFile
UploadController.java
package com.mkyong.controller;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.multipart.MultipartFile;
import org.springframework.web.servlet.mvc.support.RedirectAttributes;
import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
@Controller
public class UploadController {
//Save the uploaded file to this folder
private static String UPLOADED_FOLDER = "F://temp//";
@GetMapping("/")
public String index() {
return "upload";
@PostMapping("/upload") // //new annotation since 4.3
public String singleFileUpload(@RequestParam("file") MultipartFile file,
RedirectAttributes redirectAttributes) {
if (file.isEmpty()) {
redirectAttributes.addFlashAttribute("message", "Please select a file to upload");
return "redirect:uploadStatus";
try {
// Get the file and save it somewhere
byte[] bytes = file.getBytes();
Path path = Paths.get(UPLOADED_FOLDER + file.getOriginalFilename());
Files.write(path, bytes);
redirectAttributes.addFlashAttribute("message",
"You successfully uploaded '" + file.getOriginalFilename() + "'");
} catch (IOException e) {
e.printStackTrace();
return "redirect:/uploadStatus";
@GetMapping("/uploadStatus")
public String uploadStatus() {
return "uploadStatus";
3.2 In thymeleaf, just some normal HTML file tags.
upload.jsp
<!DOCTYPE html>
<html xmlns:th="http://www.thymeleaf.org">
<body>
<h1>Spring Boot file upload example</h1>
<form method="POST" action="/upload" enctype="multipart/form-data">
<input type="file" name="file" /><br/><br/>
<input type="submit" value="Submit" />
</form>
</body>
</html>
3.3 Another page for upload status
uploadStatus.jsp
<!DOCTYPE html>
<html lang="en" xmlns:th="http://www.thymeleaf.org">
<body>
<h1>Spring Boot - Upload Status</h1>
<div th:if="${message}">
<h2 th:text="${message}"/>
</div>
</body>
</html>
4. Max upload size exceeded
To handle the max upload size exceeded exception, declares a @ControllerAdvice and catch the MultipartException
GlobalExceptionHandler.java
package com.mkyong.controller;
import org.springframework.web.bind.annotation.ControllerAdvice;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.multipart.MultipartException;
import org.springframework.web.servlet.mvc.support.RedirectAttributes;
@ControllerAdvice
public class GlobalExceptionHandler {
//https://jira.spring.io/browse/SPR-14651
//Spring 4.3.5 supports RedirectAttributes
@ExceptionHandler(MultipartException.class)
public String handleError1(MultipartException e, RedirectAttributes redirectAttributes) {
redirectAttributes.addFlashAttribute("message", e.getCause().getMessage());
return "redirect:/uploadStatus";
/* Spring < 4.3.5
@ExceptionHandler(MultipartException.class)
public String handleError2(MultipartException e) {
return "redirect:/errorPage";
}*/
5. Tomcat Connection Reset
If you deployed to Tomcat, configure the maxSwallowSize to avoid this Tomcat connection reset issue. For embedded Tomcat, declares a TomcatEmbeddedServletContainerFactory like the following :
SpringBootWebApplication.java
package com.mkyong;
import org.apache.coyote.http11.AbstractHttp11Protocol;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.context.embedded.tomcat.TomcatConnectorCustomizer;
import org.springframework.boot.context.embedded.tomcat.TomcatEmbeddedServletContainerFactory;
import org.springframework.context.annotation.Bean;
@SpringBootApplication
public class SpringBootWebApplication {
private int maxUploadSizeInMb = 10 * 1024 * 1024; // 10 MB
public static void main(String[] args) throws Exception {
SpringApplication.run(SpringBootWebApplication.class, args);
//Tomcat large file upload connection reset
//http://www.mkyong.com/spring/spring-file-upload-and-connection-reset-issue/
@Bean
public TomcatEmbeddedServletContainerFactory tomcatEmbedded() {
TomcatEmbeddedServletContainerFactory tomcat = new TomcatEmbeddedServletContainerFactory();
tomcat.addConnectorCustomizers((TomcatConnectorCustomizer) connector -> {
if ((connector.getProtocolHandler() instanceof AbstractHttp11Protocol<?>)) {
//-1 means unlimited
((AbstractHttp11Protocol<?>) connector.getProtocolHandler()).setMaxSwallowSize(-1);
});
return tomcat;
6. Multipart File Size
By default, Spring Boot max file upload size is 1MB, you can configure the values via following application properties :
application.properties
#http://docs.spring.io/spring-boot/docs/current/reference/htmlsingle/#common-application-properties #search multipart spring.http.multipart.max-file-size=10MB spring.http.multipart.max-request-size=10MB
7. DEMO
Start Spring Boot with the default embedded Tomcat mvn spring-boot:run.
Terminal
$ mvn spring-boot:run . ____ _ __ _ _ /\\ / ___'_ __ _ _(_)_ __ __ _ \ \ \ \ ( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \ \\/ ___)| |_)| | | | | || (_| | ) ) ) ) ' |____| .__|_| |_|_| |_\__, | / / / / =========|_|==============|___/=/_/_/_/ :: Spring Boot :: (v1.4.3.RELEASE) 2017-01-21 07:48:53 INFO com.mkyong.SpringBootWebApplication - Starting SpringBootWebApplication on MKYONG-WIN10 with PID 2384 (E:\spring-boot-file-upload\target\classes started by mkyong in E:\spring-boot-file-upload) 2017-01-21 07:48:53 DEBUG com.mkyong.SpringBootWebApplication - Running with Spring Boot v1.4.3.RELEASE, Spring v4.3.5.RELEASE 2017-01-21 07:48:53 INFO com.mkyong.SpringBootWebApplication - No active profile set, falling back to default profiles: default 2017-01-21 07:48:55 INFO com.mkyong.SpringBootWebApplication - Started SpringBootWebApplication in 2.54 seconds (JVM running for 2.924)
7.1 Access http://localhost:8080/
7.2 Select a file and upload it.
7.3 Select a file larger than 10mb, you will visit this page.
8. Download Source Code
Download - spring-boot-file-upload-example.zip (7 KB)
References
- Spring Boot common application properties
- Spring MVC file upload example
- Spring @ExceptionHandler and RedirectAttributes
- Spring Boot Hello World Example – Thymeleaf
From：一号门
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