fix issue in invoices tab

cmsWebApp/src/performa/utils/StripeUtils.java

@@ -13,6 +13,7 @@ import com.stripe.model.Invoice;
 import com.stripe.model.Plan;
 import com.stripe.model.Subscription;
 import java.io.IOException;
+import java.util.ArrayList;
 import java.util.Calendar;
 import java.util.Date;
 import java.util.HashMap;
@@ -125,20 +126,23 @@ public class StripeUtils
     
     public static List<Invoice> retrieveInvoices(Company company) throws FieldException
     {
-        try 
+        if(company.getStripeSubscription() != null)
         {
-            Map<String, Object> invoiceParams = new HashMap<>();
-            
-            invoiceParams.put("subscription", company.getStripeSubscription());
-            
-            return Invoice.list(invoiceParams).getData();
-        } 
-        catch (StorageException | AuthenticationException | InvalidRequestException | APIConnectionException | CardException | APIException ex) 
-        {
-            LogMgr.log(LoggingArea.ALL, LogLevel.PROCESSING1, ex, "Error while retriving invoices in stripe for subscription: " + company.getStripeSubscription());
-        } 
+            try 
+            {
+                Map<String, Object> invoiceParams = new HashMap<>();
+
+                invoiceParams.put("subscription", company.getStripeSubscription());
+
+                return Invoice.list(invoiceParams).getData();
+            } 
+            catch (StorageException | AuthenticationException | InvalidRequestException | APIConnectionException | CardException | APIException ex) 
+            {
+                LogMgr.log(LoggingArea.ALL, LogLevel.PROCESSING1, ex, "Error while retriving invoices in stripe for subscription: " + company.getStripeSubscription());
+            } 
+        }
         
-        return null;
+        return new ArrayList<>();
     }