From 0525b2ed026e0d510fdf23f6d8f4cb4562a17e0b Mon Sep 17 00:00:00 2001
From: Kevin Lamonte <kevin.lamonte@gmail.com>
Date: Sat, 7 Apr 2018 13:49:32 -0400
Subject: [PATCH] #29 avoid potential NPE

---
 src/jexer/backend/ECMA48Terminal.java | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/src/jexer/backend/ECMA48Terminal.java b/src/jexer/backend/ECMA48Terminal.java
index 7edb64b..84f6528 100644
--- a/src/jexer/backend/ECMA48Terminal.java
+++ b/src/jexer/backend/ECMA48Terminal.java
@@ -507,9 +507,12 @@ public class ECMA48Terminal extends LogicalScreen
             e.printStackTrace();
         }
 
-        // Disable mouse reporting and show cursor
-        output.printf("%s%s%s", mouse(false), cursor(true), normal());
-        output.flush();
+        // Disable mouse reporting and show cursor.  Defensive null check
+        // here in case closeTerminal() is called twice.
+        if (output != null) {
+            output.printf("%s%s%s", mouse(false), cursor(true), normal());
+            output.flush();
+        }
 
         if (setRawMode) {
             sttyCooked();
-- 
2.27.0