Getter and Setter return null in Android

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http://stackoverflow.com – so I've been working on a project that receives data from server, for example sessionKey. I created getter and setter method like this : public class sEngine { private static String sessionKey; public static String getSessionKey() { return sessionKey; } public static void setSessionKey( String sessionKey) { sEngine.sessionKey = sessionKey; } } Then I have activity A. In this activity A, I insert a value into the setter method. public class A extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { sEngine.setSessionKey (HowTos)