excel - Producing a Java program for other systems

Question

I've been working on a Java program for a company over the summer and it is nearing completion. Being something of a novice programmer, I've never produced a program for use on other systems using files I've created. My program reads and writes to Excel using Apache Poi, and currently the Excel file being used lies in a specific directory specified by the program. The program also uses some images that lie in directories specified by the code.

How could I make this program runnable on other systems? Would it be possible to have the program create an Excel document whenever it is "installed" on another system?

Currently I'm using Eclipse and the systems are windows 7.

Answer 1

You can pack your application in a .jar, actually a zip file with inside .class files and resource files. Those resource files, like your images, can be taken with getClass().getResource("path/x.png") or getResourceAsStream. The path is either package relative or absolute: "/abc/def.jpg".

These resources must be read-only (as they are inside the .jar). However you may store an Excel template as resource, and copy that to the user's directory.

System.getProperty("user.home") 

Will give the user's directory where you may copy your resource to.

Path appWorkspace = Paths.get(System.getProperty("user.home"), "myapp");
Files.createDirectories(appWorkspace);
Path xlsx = appWorkspace.resolve("untitled.xlsx");
Files.copy(getClass().getResourceAsStream("/data/empty.xlsx"),
    xlsx);