From 893797be7ec29466d675c5d98e55c8d25b72343c Mon Sep 17 00:00:00 2001
From: Till Seeberger <seebergertill@gmail.com>
Date: Wed, 8 Jan 2020 12:00:16 +0100
Subject: [PATCH] fix NPE

---
 .../shell/ContextSubscribeCommand.java        | 26 +++++++++----------
 1 file changed, 13 insertions(+), 13 deletions(-)

diff --git a/src/main/java/com/hivemq/cli/commands/shell/ContextSubscribeCommand.java b/src/main/java/com/hivemq/cli/commands/shell/ContextSubscribeCommand.java
index 9af349358..f1aa37831 100644
--- a/src/main/java/com/hivemq/cli/commands/shell/ContextSubscribeCommand.java
+++ b/src/main/java/com/hivemq/cli/commands/shell/ContextSubscribeCommand.java
@@ -133,13 +133,10 @@ private void stay() throws InterruptedException {
             latch.countDown();
         };
 
-        final Runnable waitForExitCommandRunnable = new Runnable() {
-            @Override
-            public void run() {
-                final Scanner scanner = new Scanner(System.in);
-                scanner.nextLine();
-                latch.countDown();
-            }
+        final Runnable waitForExitCommandRunnable = () -> {
+            final Scanner scanner = new Scanner(System.in);
+            scanner.nextLine();
+            latch.countDown();
         };
 
         final ExecutorService WORKER_THREADS = Executors.newFixedThreadPool(2);
@@ -151,19 +148,22 @@ public void run() {
 
         WORKER_THREADS.shutdownNow();
 
-        if (!contextClient.getState().isConnectedOrReconnect()) {
-            removeContext();
-        }
-        else {
-            mqttClientExecutor.unsubscribe(contextClient, this);
+        if (contextClient != null) {
+            if (!contextClient.getState().isConnectedOrReconnect()) {
+                removeContext();
+            }
+            else {
+                mqttClientExecutor.unsubscribe(contextClient, this);
+            }
         }
 
+
     }
 
     @Override
     public String toString() {
         return  getClass().getSimpleName() + "{" +
-                "key=" + getKey() +
+                "key=" + ((contextClient == null)? "null" : getKey()) +
                 ", topics=" + Arrays.toString(topics) +
                 ", qos=" + Arrays.toString(qos) +
                 ", outputToConsole=" + printToSTDOUT +