Java null pointer Exception in android studio : <p>/AndroidRuntime: FATAL EXCEPTION: main
                  Process: com.example.anil.mynewapp, PID: 408
                  java.lang.NullPointerException: Attempt to invoke virtual method 'boolean com.example.anil.mynewapp.SignupAuthentication.signupAuthentication(java.lang.String, java.lang.String, java.lang.String, java.lang.String, java.lang.String)' on a null object reference
                      at com.example.anil.mynewapp.Second$1.onClick(Second.java:40)
                      at android.view.View.performClick(View.java:6294)</p>
