public class Example
{
  public String login(String username, String password) throws Exception
  {
    //login and get an auth token
    URL u = new URL("https://www.crushftp.com/");
    HttpURLConnection urlc = (HttpURLConnection)u.openConnection();
    urlc.setRequestMethod("POST");
    urlc.setUseCaches(false);
    urlc.setDoOutput(true);
    urlc.getOutputStream().write(("command=login&username="+username+"&password="+password).getBytes("UTF8"));
    urlc.getResponseCode();
    String cookie = urlc.getHeaderField("Set-Cookie");
    String auth = cookie.substring(cookie.indexOf("CrushAuth=")+"CrushAuth=".length(),cookie.indexOf(";",cookie.indexOf("CrushAuth=")));
    urlc.disconnect();
    return auth;
  }
  public void download(String auth, String serverPath, String localPath) throws Exception
  {
    //download a file using the auth token, and a post.  Alternatively you could also just do a GET on the file.
    URL u = new URL("https://www.crushftp.com/");
    HttpURLConnection urlc = (HttpURLConnection)u.openConnection();
    urlc.setRequestMethod("POST");
    urlc.setRequestProperty("Cookie", "CrushAuth="+auth+";");
    urlc.setUseCaches(false);
    urlc.setDoInput(true);
    urlc.setDoOutput(true);
    urlc.getOutputStream().write(("command=download&path=/"+serverPath).getBytes("UTF8"));
    int code = urlc.getResponseCode();
    if (urlc.getURL().toExternalForm().indexOf("/WebInterface/login.html") >= 0) code = 302;
    if (code == 302) throw new Exception("Logged out.");
    InputStream in = new BufferedInputStream(urlc.getInputStream());
    RandomAccessFile out = new RandomAccessFile(localPath,"rw");
    int bytesRead = 0;
    byte b[] = new byte[32768];
    while (bytesRead >= 0)
    {
      bytesRead = in.read(b);
      if (bytesRead >= 0) out.write(b,0,bytesRead);
    }
    in.close();
    out.close();
    urlc.disconnect();
  }
  public void upload(String auth, String serverPath, String localPath) throws Exception
  {
    //upload a file using the auth token, and a PUT.
    URL u = new URL("https://www.crushftp.com"+serverPath);
    HttpURLConnection urlc = (HttpURLConnection)u.openConnection();
    urlc.setRequestMethod("PUT");
    urlc.setRequestProperty("Cookie", "CrushAuth="+auth+";");
    urlc.setUseCaches(false);
    urlc.setChunkedStreamingMode(32768);
    urlc.setDoInput(true);
    urlc.setDoOutput(true);
    OutputStream out = urlc.getOutputStream();
    RandomAccessFile in = new RandomAccessFile(localPath,"r");
    int bytesRead = 0;
    byte b[] = new byte[32768];
    while (bytesRead >= 0)
    {
      bytesRead = in.read(b);
      if (bytesRead >= 0) out.write(b,0,bytesRead);
    }
    in.close();
    out.close();
    int code = urlc.getResponseCode();
    if (urlc.getURL().toExternalForm().indexOf("/WebInterface/login.html") >= 0) code = 302;
    if (code == 302) throw new Exception("Logged out.");
    urlc.disconnect();
  }
  public void doAction(String auth, String command, String param1, String param2) throws Exception
  {
    URL u = new URL("https://www.crushftp.com/");
    HttpURLConnection urlc = (HttpURLConnection)u.openConnection();
    urlc.setRequestMethod("POST");
    urlc.setRequestProperty("Cookie", "CrushAuth="+auth+";");
    urlc.setUseCaches(false);
    urlc.setDoOutput(true);
    String c2f = auth.substring(auth.length() - 4);
    if (command.equalsIgnoreCase("delete")) urlc.getOutputStream().write(("command=delete&names="+param1+"&c2f="+c2f).getBytes("UTF8"));
    else if (command.equalsIgnoreCase("rename")) urlc.getOutputStream().write(("command=rename&name1="+param1+"&name2="+param2+"&c2f="+c2f).getBytes("UTF8"));
    else if (command.equalsIgnoreCase("makedir")) urlc.getOutputStream().write(("command=makedir&path="+param1+"&c2f="+c2f).getBytes("UTF8"));
    else if (command.equalsIgnoreCase("getXMLListing")) urlc.getOutputStream().write(("command=getXMLListing&path="+param1+"&c2f="+c2f).getBytes("UTF8"));
    int code = urlc.getResponseCode();
    if (urlc.getURL().toExternalForm().indexOf("/WebInterface/login.html") >= 0) code = 302;
    if (code == 302) throw new Exception("Logged out.");
    urlc.disconnect();
  }
}