uploading images to server in spring MVC and storing reference in mysql database

Question

I'm coding a Spring MVC 3.0 application with Tomcat as the web server.

Our requirement is to let the user upload an image. I'm thinking of storing this image on the disk file system and store the reference path in MySQL instead of storing all the file info in MySQL database as BLOB (I was told storing in MySQL is not best practice).

Can any one recommend how to do this in Spring MVC?

Cheers

Solution

Storing in disk and storing in MySQL has its on caveats. Here is good discussion about it.

To store it in file system you can use Commons File Upload. Here is a sample

pom.xml

     <dependency>
        <groupId>commons-fileupload</groupId>
        <artifactId>commons-fileupload</artifactId>
        <version>${release.version}</version>
    </dependency>

    <dependency>
        <groupId>commons-io</groupId>
        <artifactId>commons-io</artifactId>
        <version>${release.version}</version>
    </dependency>

JSP

<h2>Spring MVC file upload example</h2>

<form method="POST" action="<c:url value='/upload' />"
    enctype="multipart/form-data">


    Please select a file to upload : <input type="file" name="file" />
    <input type="submit" value="upload" />

</form>

Controller

@RequestMapping(value = "/upload", method = RequestMethod.POST)
public String handleFormUpload( 
    @RequestParam("file") MultipartFile file) throws IOException{
if (!file.isEmpty()) {
 BufferedImage src = ImageIO.read(new ByteArrayInputStream(file.getBytes()));
 File destination = new File("File directory with file name") // something like C:/Users/tom/Documents/nameBasedOnSomeId.png
 ImageIO.write(src, "png", destination);
 //Save the id you have used to create the file name in the DB. You can retrieve the image in future with the ID.
 }  
}

And define this in your application context

 <bean id="multipartResolver"
    class="org.springframework.web.multipart.commons.CommonsMultipartResolver">

I hope this helps.