image file creation through application

I have created an application in which the android mobile takes picture and uploads it to a server.The server application is developed in vaadin. The server accepts the image, stores in local directory and updates the path to the database. Everything works fine on my localhost (Windows) but when i deploy the war file it is not creating the file. The problem is my localhost is on windows but the main server(ISP) is on Linux. Both my localhost and main server (ISP) are using glassfish. On the main server (ISP) I am logging through admin and then deploying the war file.