Error in displaying image using stream Result

[Mumtaz Khan]

I am developing a web application in struts2 where I need to display image on jsp pages. Many questions have been asked in different forums but I am not be to get solution for my problem.
My application receives images in form of file through mobile application which is being developed in Titanium. I am saving the file as :

FileInputStream fis = new FileInputStream(file);
ps.setBinaryStream(3, fis, (int) file.length());

which saves it as long blob. format of images png.
I am trying to retrieve it in my action class and setting it to inputStream. Here is the code for this:

 public String getImageFileStream()
     {    	
	....
	imageStream = abc.getImageStream();
    	....			
       }
    private InputStream imageStream;					
    public InputStream getImageStream() throws Exception{
	 return imageStream;
}

Entry of struts.xml file is :

<action name="getImage" class="com........Action" method="getImageFileStream" >
     	 		<result name="success" type="stream">
   					<param name="contentType">image/png</param>
   					<param name="inputName">imageStream</param>
   					<param name="contentDisposition">filename="image.png"</param>
   					<param name="bufferSize">1024</param>
 				</result>
     	</action>

In jsp I am calling the action as:

<img src="<s:url action="getImage">/>

I am able to retrieve the image from database and save in /images under webcontent but not able to display using stream. It says: The image ",......" cannot be displayed because it contains error. I am not getting any exception in log files. In stdout I am getting this:

2011-04-14 20:00:19,051 DEBUG org.apache.struts2.dispatcher.StreamResult.debug:68 - Streaming result [imageStream] type=[image/png] length=[0] content-disposition=[inline] charset=[null]
2011-04-14 20:00:19,052 DEBUG org.apache.struts2.dispatcher.StreamResult.debug:68 - Streaming to output buffer +++ START +++
2011-04-14 20:00:19,052 DEBUG org.apache.struts2.dispatcher.StreamResult.debug:68 - Streaming to output buffer +++ END +++

I am not able to understand why image is not being able to displayed? Is it because of length?If so how can I get contentLength for inputStream?
Please help.

Thanks in advance!