document_type.java

public static String documentType(String file)
    {
        String fileType = "Undetermined";
        try
        {
            final URL url = new URL("file://" + file);
            final URLConnection connection = url.openConnection();
            fileType = connection.getContentType();
        }
        catch (MalformedURLException badUrlEx)
        {
            System.out.println("ERROR: Bad URL - " + badUrlEx);
        }

        catch (IOException ioEx)
        {
            System.out.println("Cannot access URLConnection - " + ioEx);
        }

        return fileType;
    }