Identify path or letter of DVD drive in autorun

Question

I am creating an application that must be run by DVD-R, and you also need to run background programs using the command process.start("D:\Local do arquivo").

But there is my doubt: if the client has distributions on the computer the disk location will no longer be the D:\ and yes the F:\.

How do I get the program to run and another background program even if the units are different?

Answer 1

If the application is on the same drive as the other application that will be fired, you can identify the drive of your application and then form the complete path of the second application.

For example, instead of fixing that other application (in my example, applitivo2.exe) is in D: Location of the application file2.exe, fix only your path relative to the root drive and create the full path from the root drive of the application that will run it:

    String caminhoApp = System.getProperty("user.dir");
    String unidadeApp = caminhoApp.substring(0, caminhoApp.indexOf(File.separator));

    System.out.println(unidadeApp);

    String nomeOutroApp = String.format("Local do arq%saplicativo2.exe", File.separator);
    String caminhoOutroApp = new File(unidadeApp ,nomeOutroApp).getPath();

    System.out.println(caminhoOutroApp);

If you do not know on which drive the other application will be on, you can do a search for drives. For example:

public String localizaOutroApp(String caminhoRelativoARaiz) {
    File[] unidades = File.listRoots();
    for(int i = 0; i < unidades.length ; i++) {
        File arquivo = new File(unidades[i], caminhoRelativoARaiz);
        if (arquivo.exists()) {
            return arquivo.getPath();
        }
    }
    return null;
}

Passing to the above function the path of the other application relative to the root, it will return the complete path of the other application no matter on which drive it has been found. Example:

// se o existe "F:\Local do arquivo\aplicativo2.exe", é este caminho que será impresso.
System.out.println(localizaOutroApp("Local do arquivo\\aplicativo2.exe"));

_{In the second example I used " instead of "File.separator" to make it easier to read. Always use "File.separator" if you want portability between operating systems.}