Spring Cookbook

Uploading a file

To allow a user to upload a file from an HTML form, we need to set the form encoding to multipart/form-data. On the server side, we will use the fileupload package from the Apache Commons library to process the uploaded file.

How to do it…

Here are the steps to upload a file from a form:

1. Add the Maven dependency for fileupload from Apache Commons in pom.xml:

   <dependency>
     <groupId>commons-fileupload</groupId>
     <artifactId>commons-fileupload</artifactId>
     <version>1.3.1</version>
   </dependency>

2. In the Spring configuration, declare a MultipartResolver bean with a size limit (in bytes) for the data to be uploaded:

   @Bean MultipartResolver multipartResolver() { CommonsMultipartResolver resolver = new CommonsMultipartResolver(); resolver.setMaxUploadSize(500000000); ...