Do not ask to close if finished

src/main/java/org/lalber/tools/exifrotation/Main.java

@@ -19,6 +19,7 @@ public class Main {
 
     private static Thread processingThread;
     private static boolean aborted;
+    private static boolean finished;
 
     /**
      * Main entry point to application.
@@ -47,6 +48,7 @@ public class Main {
         frame.setDefaultCloseOperation(JFrame.DO_NOTHING_ON_CLOSE);
         frame.addWindowListener(new WindowAdapter(){
             public void windowClosing(WindowEvent e) {
+                if (!finished) {
                     if (JOptionPane.showConfirmDialog(frame, "Abort and Close?") == 0) {
                         aborted = true;
                         if (processingThread != null) {
@@ -58,6 +60,7 @@ public class Main {
                         }
                         System.exit(0);
                     }
+                } else System.exit(0);
             }
         });
 
@@ -84,6 +87,7 @@ public class Main {
                 e.printStackTrace();
             }
 
+            finished = true;
             textArea.append("FINISHED!");
         });