Create final SimpleDateFormat instance only when creating ExpiryWatcher instance

Author: emmanuelkehinde

raveandroid/src/main/java/com/flutterwave/raveandroid/card/CardFragment.java

@@ -835,10 +835,12 @@ public void onPageFinished(WebView view, String url) {
     private class ExpiryWatcher implements TextWatcher {
 
         private final Calendar calendar;
+        private final SimpleDateFormat simpleDateFormat;
         private String lastInput = "";
 
         public ExpiryWatcher() {
             calendar = Calendar.getInstance();
+            simpleDateFormat = new SimpleDateFormat("MM/yy");
         }
 
         @Override
@@ -854,7 +856,6 @@ public void onTextChanged(CharSequence charSequence, int i, int i1, int i2) {
         @Override
         public void afterTextChanged(Editable editable) {
             String input = editable.toString();
-            SimpleDateFormat simpleDateFormat = new SimpleDateFormat("MM/yy");
 
             try {
                 calendar.setTime(simpleDateFormat.parse(input));