GuiChoose.order is also always invoked by EDT.

Found a right wrapper class to pass Callables to EDT,

src/main/java/forge/FThreads.java

@@ -16,13 +16,6 @@ import forge.control.input.InputSynchronized;
  */
 public class FThreads {
     
-    // This could be some bad copy of SwingWorker
-    public abstract static class RunnableWithResult<T> implements Runnable {
-        protected T result = null;
-        public T getResult() { return result; }
-
-    }
-    
     static { 
         System.out.printf("(FThreads static ctor): Running on a machine with %d cpu core(s)%n", Runtime.getRuntime().availableProcessors() );
     }

src/main/java/forge/gui/GuiChoose.java

@@ -8,6 +8,9 @@ import java.util.Collections;
 import java.util.Comparator;
 import java.util.List;
 import java.util.concurrent.Callable;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.Future;
+import java.util.concurrent.FutureTask;
 
 import javax.swing.JDialog;
 import javax.swing.JFrame;
@@ -104,10 +107,9 @@ public class GuiChoose {
             }
         }
         
-        FThreads.RunnableWithResult<List<T>> showChoice = new FThreads.RunnableWithResult<List<T>>() {
+        Callable<List<T>> showChoice = new Callable<List<T>>() {
-            
             @Override
-            public void run() {
+            public List<T> call() {
                 ListChooser<T> c = new ListChooser<T>(message, min, max, choices);
                 final JList list = c.getJList();
                 list.addListSelectionListener(new ListSelectionListener() {
@@ -126,12 +128,18 @@ public class GuiChoose {
                 });
                 c.show();
                 GuiUtils.clearPanelSelections();
-                result = c.getSelectedValues();
+                return c.getSelectedValues();
             }
         };
 
-        FThreads.invokeInEDTAndWait(showChoice);
+        FutureTask<List<T>> future = new FutureTask<List<T>>(showChoice);
-        return showChoice.getResult();
+        FThreads.invokeInEDTAndWait(future);
+        try { 
+            return future.get();
+        } catch (Exception e) { // should be no exception here
+            e.printStackTrace();
+        }
+        return null;
     }
 
     // Nothing to choose here. Code uses this to just show a card.
@@ -153,39 +161,54 @@ public class GuiChoose {
     }
 
     
-    public static <T> List<T> order(final String title, final String top, int remainingObjects,
+    public static <T> List<T> order(final String title, final String top, final int remainingObjects,
-            final List<T> sourceChoices, List<T> destChoices, Card referenceCard, boolean sideboardingMode) {
+            final List<T> sourceChoices, final List<T> destChoices, final Card referenceCard, final boolean sideboardingMode) {
         // An input box for handling the order of choices.
-        final JFrame frame = new JFrame();
+        
-        DualListBox<T> dual = new DualListBox<T>(remainingObjects, sourceChoices, destChoices);
+        Callable<List<T>> callable = new Callable<List<T>>() {
-        dual.setSecondColumnLabelText(top);
+            @Override
+            public List<T> call() throws Exception {
+                final JFrame frame = new JFrame();
+                DualListBox<T> dual = new DualListBox<T>(remainingObjects, sourceChoices, destChoices);
+                dual.setSecondColumnLabelText(top);
+        
+                frame.setLayout(new BorderLayout());
+                frame.setSize(dual.getPreferredSize());
+                frame.add(dual);
+                frame.setTitle(title);
+                frame.setVisible(false);
+        
+                dual.setSideboardMode(sideboardingMode);
+        
+                final JDialog dialog = new JDialog(frame, true);
+                dialog.setTitle(title);
+                dialog.setContentPane(dual);
+                dialog.setSize(dual.getPreferredSize());
+                dialog.setLocationRelativeTo(null);
+                dialog.pack();
+                dialog.setDefaultCloseOperation(WindowConstants.DO_NOTHING_ON_CLOSE);
+                if (referenceCard != null) {
+                    CMatchUI.SINGLETON_INSTANCE.setCard(referenceCard);
+                    // MARKED FOR UPDATE
+                }
+                dialog.setVisible(true);
+        
+                List<T> objects = dual.getOrderedList();
+        
+                dialog.dispose();
+                GuiUtils.clearPanelSelections();
+                return objects;
+            }
+        };
 
-        frame.setLayout(new BorderLayout());
+        FutureTask<List<T>> ft = new FutureTask<List<T>>(callable);
-        frame.setSize(dual.getPreferredSize());
+        FThreads.invokeInEDTAndWait(ft);
-        frame.add(dual);
+        try {
-        frame.setTitle(title);
+            return ft.get();
-        frame.setVisible(false);
+        } catch (Exception e) { // we have waited enough
-
+            e.printStackTrace();
-        dual.setSideboardMode(sideboardingMode);
-
-        final JDialog dialog = new JDialog(frame, true);
-        dialog.setTitle(title);
-        dialog.setContentPane(dual);
-        dialog.setSize(dual.getPreferredSize());
-        dialog.setLocationRelativeTo(null);
-        dialog.pack();
-        dialog.setDefaultCloseOperation(WindowConstants.DO_NOTHING_ON_CLOSE);
-        if (referenceCard != null) {
-            CMatchUI.SINGLETON_INSTANCE.setCard(referenceCard);
-            // MARKED FOR UPDATE
         }
-        dialog.setVisible(true);
+        return null;
-
-        List<T> objects = dual.getOrderedList();
-
-        dialog.dispose();
-        GuiUtils.clearPanelSelections();
-        return objects;
     }
 
     // If comparer is NULL, T has to be comparable. Otherwise you'll get an exception from inside the Arrays.sort() routine