How to handle file upload from web service

I'm developing an Iphone/Android application. I need to create a web service for handling u开发者_JS百科ploading images.

Mobile devices can send images to my web service.

How can i handle sent files in java?

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Easiest way would be to read the image into a byte array on the client side, then send that over the web-service and convert it back into an image on the server side.