Question

I am currently working on an application named BlackBerry Contacts Sync and I am stuck at this point on how to sync Contact’s Image. How can images be stored in the database (MySQL) and how to retrieve them?

Answer 1

If you want to store your images in the database instead of just a path to reference the image, the column that will hold your image need to be of BLOB type.

CREATE TABLE upload (
    id INT NOT NULL AUTO_INCREMENT,
    name VARCHAR(30) NOT NULL,
    content LONGBLOB NOT NULL,
    PRIMARY KEY(id)
);

From your BlackBerry program (warning, untested):

//First param is a Bitmap, second is quality
JPEGEncodedImage encodedImage = JPEGEncodedImage.encode(image, 100);
byte imageBytes[]=encodedImage.getData();

//The HTTP connection stuff
HttpConnection conn = (HttpConnection) Connector.open(SERVER_URL, Connector.READ_WRITE);
conn.setRequestProperty(HttpProtocolConstants.HEADER_CONTENT_TYPE, HttpProtocolConstants.CONTENT_TYPE_MULTIPART_FORM_DATA);
conn.setRequestMethod(HttpConnection.POST);
conn.setRequestProperty(HttpProtocolConstants.HEADER_CONTENT_LENGTH, String.valueOf(imageBytes.length));
//Change this part to what your server side code expects
String contDisp="Content-Disposition:form-data; uploadedimage=YOUR_IMAGE_NAME;filename=\"Image.jpg\"";
String contEnc = "Content-Transfer-Encoding: binary";
String type="Content-Type:image/jpeg";

OutputStream out= conn.openOutputStream();
out.write(imageBytes);
out.flush();
out.close();

So basically you use HttpConnection to setup the headers for a POST request, with multipart form data as content type. There are other headers that may be needed, to know exactly what you need (not BlackBerry specific) check the HTTP/1.1 protocol specification.

How to actually store the image into the database will depend on your server side implementation. This can be anything from PHP, ASP, JSP or any server side technology that allows you to talk to your MySQL instance.