Recursive evaluation of the size of a folder

Establish a path to any object the size of this strike a path to the folder:
 public class the Test { 
    public static void main (String [] args) throws IOException {
 // Create a file object
         File file = new File ( "D : \\ JavaSE "); 
        System.out.println (method (file)); 
    }
 // methods seeking to write the file size
     public static Long method (file file) { 
        Long Line = 0L; 
        IF (file.isDirectory ()) { 
            file [] files File.listFiles = (); 
            for (file1 File: Files) { 
               Line = Method + (file1); 
            } 
        } 
        return Line file.length + = (); 
    } 
}