Upload image and display in browser in spring webflow - spring

Question

I had a requirement of getting the image from the filesystem and displaying it in browser. The code i had tried till now is shown below:
.jsp code:
<formspring:form enctype="multipart/form-data" modelAttribute="onlinePurchase">
Please select a file to upload : <input type="file" name="multipartFileUpload" id="multipartFileUpload" />
<div class="submit">
<input type="submit" id="upload" name="_eventId_upload"
value="Upload Image" />
</div>
</formspring:form>
controller code:
public void saveImage(OnlinePurchase onlinepurchase,
MultipartFile multipartFile) {
try {
onlinepurchase.setContent(multipartFile.getBytes());
} catch (IOException e) {
e.printStackTrace();
}
onlinepurchase.setContentSize(new Long(multipartFile.getSize())
.intValue());
onlinepurchase.setContentType(multipartFile.getContentType());
onlinepurchase.setFilename(multipartFile.getOriginalFilename());
}
flow.xml code:
<view-state id="onlinePurchaseStep1" view="onlinepurchase/onlinepurchaserequest-step-1"
model="onlinePurchase">
<on-render>
<evaluate expression="oPAction.initialize" />
</on-render>
<transition on="submit" to="onlinePurchaseStep1" validate="false">
<evaluate expression="oPAction.cropImage" />
</transition>
<transition on="upload" to="onlinePurchaseStep1" validate="false">
<evaluate
expression="oPAction.saveImage(onlinePurchase,requestParameters.multipartFileUpload)"
result="" result-type="" />
</transition>
<transition on="success" to="onlinePurchaseStep2">
<evaluate expression="oPAction.addMedia" />
</transition>
<transition on="cancel" to="login" validate="false" />
</view-state>
The issue is that saveImage(OnlinePurchase onlinepurchase, String multipartFile) method in action is not getting called.
Any suggestions are appreciated.

Answer 1

You need a MultipartResolver :
add this line in your springs's webmvc xml configuration file.
<bean id ="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver"/>
Note that the CommonsMultipartResolver uses classes from org.apache.commons.io package so you may need to add commons-io.jar in your classpath.
If your project is maven you can add the following dependency in the pom:
<dependency>
<groupId>org.apache.commons</groupId>
<artifactId>commons-io</artifactId>
<version>a valid version</version> <!-- 2.4 worked for me -->
</dependency>