From ebb2fe458bcd2b8d29d2b5c86815db8eb4f2b908 Mon Sep 17 00:00:00 2001
From: Adrian Nistor <adrnisto@amazon.com>
Date: Tue, 25 Jun 2019 21:02:45 +0000
Subject: [PATCH] HashMap is not thread safe.  The existing synchronzed(map) is
 too small, should be extended to cover the surrounding code.

---
 .../src/main/java/mage/client/util/gui/ArrowBuilder.java | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/Mage.Client/src/main/java/mage/client/util/gui/ArrowBuilder.java b/Mage.Client/src/main/java/mage/client/util/gui/ArrowBuilder.java
index 3520af3b4c..b471998a53 100644
--- a/Mage.Client/src/main/java/mage/client/util/gui/ArrowBuilder.java
+++ b/Mage.Client/src/main/java/mage/client/util/gui/ArrowBuilder.java
@@ -112,10 +112,11 @@ public class ArrowBuilder {
      * Removes all arrows from the screen.
      */
     public void removeAllArrows(UUID gameId) {
-        if (map.containsKey(gameId)) {
-            Map<Type, List<Arrow>> innerMap = map.get(gameId);
-            JPanel p = getArrowsPanel(gameId);
-            synchronized (map) {
+        synchronized (map) {
+            if (map.containsKey(gameId)) {
+                Map<Type, List<Arrow>> innerMap = map.get(gameId);
+                JPanel p = getArrowsPanel(gameId);
+
                 if (p != null && p.getComponentCount() > 0) {
                     p.removeAll();
                     p.revalidate();