From 87a68e4e69cc0a96adaf169fc1a9f9a02f1a6054 Mon Sep 17 00:00:00 2001
From: Steve Gury <stevegury@users.noreply.github.com>
Date: Mon, 24 Aug 2015 16:49:22 -0700
Subject: [PATCH] MacOSX WatchService check for null file in recursiveListFiles

It's possible to have listFiles return a null in specific conditions (I believe if the directory is deleted).
This code should check for that before using the file variable.
---
 .../watchservice/MacOSXListeningWatchService.java      | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/src/main/java/com/barbarysoftware/watchservice/MacOSXListeningWatchService.java b/src/main/java/com/barbarysoftware/watchservice/MacOSXListeningWatchService.java
index 8dadadd..47fc2b2 100644
--- a/src/main/java/com/barbarysoftware/watchservice/MacOSXListeningWatchService.java
+++ b/src/main/java/com/barbarysoftware/watchservice/MacOSXListeningWatchService.java
@@ -110,10 +110,12 @@ private Map<File, Long> createLastModifiedMap(File file) {
 
     private static Set<File> recursiveListFiles(File file) {
         Set<File> files = new HashSet<File>();
-        files.add(file);
-        if (file.isDirectory()) {
-            for (File child : file.listFiles()) {
-                files.addAll(recursiveListFiles(child));
+        if (file != null) {
+            files.add(file);
+            if (file.isDirectory()) {
+                for (File child : file.listFiles()) {
+                    files.addAll(recursiveListFiles(child));
+                }
             }
         }
         return files;