How to obscure only 1 String or the whole activity

Question

I want to obscures only 1 String . He is here ,

package x.y.z

public class MainActivity extends AppCompatActivity {

@Override
    protected Void doInBackground(Void... arg0) {
String url = "https://example.com/app_update/userdata.json";
.
.
.
`
}

How to obscures it please help

Answer 1

I would just do it manually. You could generate it out of parts or use some sort of encryption.

Here is also an example how to do it: https://gist.github.com/slevental/0c902da60a1f6f931420