Java tutorial
import java.io.IOException; import java.nio.file.FileStore; import java.nio.file.FileSystem; import java.nio.file.FileSystems; public class Main { public static void main(String[] args) throws IOException { FileSystem fileSystem = FileSystems.getDefault(); for (FileStore store : fileSystem.getFileStores()) { long total = store.getUnallocatedSpace() / 1024; System.out.println(total); } } }