From 9bec5e1caef4e44d1e55f6334cb57649fda3846c Mon Sep 17 00:00:00 2001
From: Greg Peterson <gpeterson@bravurasolutions.com>
Date: Fri, 21 Feb 2020 09:24:16 +1030
Subject: [PATCH] Ensure repeated headers only have values logged once

---
 java/org/apache/catalina/filters/RequestDumperFilter.java | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/java/org/apache/catalina/filters/RequestDumperFilter.java b/java/org/apache/catalina/filters/RequestDumperFilter.java
index aad5956be3..52e56c3185 100644
--- a/java/org/apache/catalina/filters/RequestDumperFilter.java
+++ b/java/org/apache/catalina/filters/RequestDumperFilter.java
@@ -21,6 +21,7 @@ import java.io.ObjectInputStream;
 import java.text.SimpleDateFormat;
 import java.util.Date;
 import java.util.Enumeration;
+import java.util.LinkedHashSet;
 
 import jakarta.servlet.FilterChain;
 import jakarta.servlet.GenericFilter;
@@ -217,7 +218,7 @@ public class RequestDumperFilter extends GenericFilter {
         if (hResponse == null) {
             doLog("            header", NON_HTTP_RES_MSG);
         } else {
-            Iterable<String> rhnames = hResponse.getHeaderNames();
+            Iterable<String> rhnames = new LinkedHashSet<>(hResponse.getHeaderNames());
             for (String rhname : rhnames) {
                 Iterable<String> rhvalues = hResponse.getHeaders(rhname);
                 for (String rhvalue : rhvalues) {
-- 
2.24.0.windows.2