From eba76c643e44347d7dc295f71f54530e658313b3 Mon Sep 17 00:00:00 2001
From: Grzegorz Grzybek <gr.grzybek@gmail.com>
Date: Fri, 15 Sep 2023 10:43:05 +0200
Subject: [PATCH] [Fixes #529] Prevent NPE when context map is null

(cherry picked from commit c7a831315f8b48cbde6c2fb3564e0f6267303c6e)
---
 .../java/org/ops4j/pax/logging/slf4j/Slf4jMDCAdapter.java     | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/pax-logging-api/src/main/java/org/ops4j/pax/logging/slf4j/Slf4jMDCAdapter.java b/pax-logging-api/src/main/java/org/ops4j/pax/logging/slf4j/Slf4jMDCAdapter.java
index 76e8e226..865b28e5 100644
--- a/pax-logging-api/src/main/java/org/ops4j/pax/logging/slf4j/Slf4jMDCAdapter.java
+++ b/pax-logging-api/src/main/java/org/ops4j/pax/logging/slf4j/Slf4jMDCAdapter.java
@@ -17,6 +17,7 @@
  */
 package org.ops4j.pax.logging.slf4j;
 
+import java.util.Collections;
 import java.util.Deque;
 import java.util.HashMap;
 import java.util.Map;
@@ -88,6 +89,9 @@ public void clear() {
     public Map<String, String> getCopyOfContextMap() {
         Map<String, Object> copy = getContext().getCopyOfContextMap();
         Map<String, String> result = new HashMap<>();
+        if (copy == null) {
+            return Collections.emptyMap();
+        }
         copy.forEach((k, v) -> {
             if (v instanceof String) {
                 result.put(k, (String) v);