Authenticating a user (in the web application typically Servlet) with his credentials from Android application

I am trying to develop an Android application which typically allows users to login (authentication has to be done in the web application. I already have a Servlet which takes username and password and returns success or failure as result in XML format) with their credentials and do some operations (like view, update delete) on the 开发者_Python百科data specific to that user.

I found that we have to use REST way of doing this. I am not sure if I understood it correctly. Can someone direct me the way I should proceed to develop this kind of Android application?

Thanks, Prasanth

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The easiest way I did this was using GET. Just load the credentials to your URL and load that url

username = et1.getText().toString(); password = et2.getText().toString();

String url = "http://www.abc.com?action=ru?loginid="+username+"paswd="+password; wv.loadUrl(url);

If you just do the above, you can see "successful" on your screen. If you want to catch this and put a validation, do the following:

                            InputStream isText = text.openStream();

                        byte[] bytes=new byte[isText.available()];
                        isText.read(bytes);
                        String s = new String(bytes);
                        System.out.println(s);

                        if(s.equals("unavailable"))

                        {

                        String s1="OK";
                    AlertDialog.Builder ad=new AlertDialog.Builder(Registration.this);

                           ad.setMessage("username already exists");
                           ad.setPositiveButton(s1, new DialogInterface.OnClickListener()
                           {
                                public void onClick(DialogInterface dialog, int which) 
                            {

                            }

                           });
                                   ad.show();

                        return;

                    }