Spring Boot无法上传大于1MB文件：遇FileSizeLimitExceededException异常

Got it, let's tackle that org.apache.tomcat.util.http.fileupload.FileUploadBase$FileSizeLimitExceededException you're seeing. This happens because Spring Boot sets a default maximum file upload size of 1MB out of the box. Here's how to adjust this based on your Spring Boot version:

For Spring Boot 2.0+ (including 3.x) #

The easiest way is to update your application configuration file (either application.properties or application.yml):

Using application.properties #

# Maximum size for a single uploaded file
spring.servlet.multipart.max-file-size=10MB
# Maximum total size for all files in a single request
spring.servlet.multipart.max-request-size=20MB

Using application.yml #

spring:
  servlet:
    multipart:
      max-file-size: 10MB
      max-request-size: 20MB

You can use units like KB, MB, or GB depending on your needs—just make sure the unit is uppercase (e.g., MB not mb).

For Spring Boot 1.x #

The configuration prefix is slightly different here:

Using application.properties #

spring.http.multipart.max-file-size=10MB
spring.http.multipart.max-request-size=20MB

Using application.yml #

spring:
  http:
    multipart:
      max-file-size: 10MB
      max-request-size: 20MB

Alternative: Programmatic Configuration #

If you need more flexibility (like setting a custom temp file location), you can create a configuration class:

import org.springframework.boot.web.servlet.MultipartConfigFactory;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import javax.servlet.MultipartConfigElement;

@Configuration
public class FileUploadConfig {

    @Bean
    public MultipartConfigElement multipartConfigElement() {
        MultipartConfigFactory factory = new MultipartConfigFactory();
        
        // Set max size per file
        factory.setMaxFileSize("10MB");
        // Set max total size for all files in one request
        factory.setMaxRequestSize("20MB");
        // Optional: Set a custom temp directory to avoid permission issues
        factory.setLocation(System.getProperty("java.io.tmpdir"));
        
        return factory.createMultipartConfig();
    }
}

Quick Notes #

• If you're using a non-Tomcat container (like Jetty or Undertow), these configurations still work—Spring Boot's auto-config handles the container-specific adjustments.
• If you still hit limits after updating, check if there's an upstream proxy (like Nginx) or frontend code enforcing smaller file sizes.

内容的提问来源于stack exchange，提问作者Shiva Kumar N