diff --git a/.settings.xml b/.settings.xml
index 6c355129e..08951cafd 100644
--- a/.settings.xml
+++ b/.settings.xml
@@ -21,7 +21,7 @@
 		<repository>
 			<id>spring-snapshots</id>
 			<name>Spring Snapshots</name>
-			<url>http://repo.spring.io/libs-snapshot-local</url>
+			<url>https://repo.spring.io/libs-snapshot-local</url>
 			<snapshots>
 				<enabled>true</enabled>
 			</snapshots>
@@ -29,7 +29,7 @@
 		<repository>
 			<id>spring-milestones</id>
 			<name>Spring Milestones</name>
-			<url>http://repo.spring.io/libs-milestone-local</url>
+			<url>https://repo.spring.io/libs-milestone-local</url>
 			<snapshots>
 				<enabled>false</enabled>
 			</snapshots>
@@ -37,7 +37,7 @@
 		<repository>
 			<id>spring-releases</id>
 			<name>Spring Releases</name>
-			<url>http://repo.spring.io/release</url>
+			<url>https://repo.spring.io/release</url>
 			<snapshots>
 				<enabled>false</enabled>
 			</snapshots>
@@ -47,7 +47,7 @@
 		<pluginRepository>
 			<id>spring-snapshots</id>
 			<name>Spring Snapshots</name>
-			<url>http://repo.spring.io/libs-snapshot-local</url>
+			<url>https://repo.spring.io/libs-snapshot-local</url>
 			<snapshots>
 				<enabled>true</enabled>
 			</snapshots>
@@ -55,7 +55,7 @@
 		<pluginRepository>
 			<id>spring-milestones</id>
 			<name>Spring Milestones</name>
-			<url>http://repo.spring.io/libs-milestone-local</url>
+			<url>https://repo.spring.io/libs-milestone-local</url>
 			<snapshots>
 				<enabled>false</enabled>
 			</snapshots>
diff --git a/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl-config.xml b/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl-config.xml
index e4d677fc5..e354da15f 100644
--- a/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl-config.xml
+++ b/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl-config.xml
@@ -19,5 +19,5 @@
 	<highlighter id="properties" file="./xslthl/properties-hl.xml" />
 	<highlighter id="json" file="./xslthl/json-hl.xml" />
 	<highlighter id="yaml" file="./xslthl/yaml-hl.xml" />
-	<namespace prefix="xslthl" uri="http://xslthl.sf.net" />
+	<namespace prefix="xslthl" uri="http://xslthl.sourceforge.net/" />
 </xslthl-config>
diff --git a/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/bourne-hl.xml b/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/bourne-hl.xml
index e2cd98d8b..90408acc6 100644
--- a/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/bourne-hl.xml
+++ b/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/bourne-hl.xml
@@ -4,7 +4,7 @@
 Syntax highlighting definition for SH
 
 xslthl - XSLT Syntax Highlighting
-http://sourceforge.net/projects/xslthl/
+https://sourceforge.net/projects/xslthl/
 Copyright (C) 2010 Mathieu Malaterre
 
 This software is provided 'as-is', without any express or implied
diff --git a/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/c-hl.xml b/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/c-hl.xml
index 176cc379f..7363dba91 100644
--- a/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/c-hl.xml
+++ b/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/c-hl.xml
@@ -3,7 +3,7 @@
 Syntax highlighting definition for C
 
 xslthl - XSLT Syntax Highlighting
-http://sourceforge.net/projects/xslthl/
+https://sourceforge.net/projects/xslthl/
 Copyright (C) 2005-2008 Michal Molhanec, Jirka Kosek, Michiel Hendriks
 
 This software is provided 'as-is', without any express or implied
diff --git a/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/cpp-hl.xml b/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/cpp-hl.xml
index ef83c4f5e..b31f73622 100644
--- a/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/cpp-hl.xml
+++ b/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/cpp-hl.xml
@@ -4,7 +4,7 @@
 Syntax highlighting definition for C++
 
 xslthl - XSLT Syntax Highlighting
-http://sourceforge.net/projects/xslthl/
+https://sourceforge.net/projects/xslthl/
 Copyright (C) 2005-2008 Michal Molhanec, Jirka Kosek, Michiel Hendriks
 
 This software is provided 'as-is', without any express or implied
diff --git a/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/csharp-hl.xml b/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/csharp-hl.xml
index d57e63102..09373348a 100644
--- a/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/csharp-hl.xml
+++ b/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/csharp-hl.xml
@@ -4,7 +4,7 @@
 Syntax highlighting definition for C#
 
 xslthl - XSLT Syntax Highlighting
-http://sourceforge.net/projects/xslthl/
+https://sourceforge.net/projects/xslthl/
 Copyright (C) 2005-2008 Michal Molhanec, Jirka Kosek, Michiel Hendriks
 
 This software is provided 'as-is', without any express or implied
diff --git a/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/css-hl.xml b/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/css-hl.xml
index 164c48c3d..21439ae69 100644
--- a/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/css-hl.xml
+++ b/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/css-hl.xml
@@ -4,7 +4,7 @@
 Syntax highlighting definition for CSS files
 
 xslthl - XSLT Syntax Highlighting
-http://sourceforge.net/projects/xslthl/
+https://sourceforge.net/projects/xslthl/
 Copyright (C) 2011-2012 Martin Hujer, Michiel Hendriks
 
 This software is provided 'as-is', without any express or implied
@@ -26,7 +26,7 @@ freely, subject to the following restrictions:
 Martin Hujer <mhujer at users.sourceforge.net>
 Michiel Hendriks <elmuerte at users.sourceforge.net>
 
-Reference: http://www.w3.org/TR/CSS21/propidx.html
+Reference: https://www.w3.org/TR/CSS21/propidx.html
 
 -->
 <highlighters>
diff --git a/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/html-hl.xml b/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/html-hl.xml
index 5b6761bab..366cd46f2 100644
--- a/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/html-hl.xml
+++ b/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/html-hl.xml
@@ -7,7 +7,7 @@
   myxml-hl.xml - konfigurace zvyraznovace XML, ktera zvlast zvyrazni
                  HTML elementy a XSL elementy
 
-  This file has been customized for the Asciidoctor project (http://asciidoctor.org).
+  This file has been customized for the Asciidoctor project (https://asciidoctor.org).
 -->
 <highlighters>
   <highlighter type="xml">
diff --git a/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/ini-hl.xml b/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/ini-hl.xml
index 34c103637..6bd60b3e3 100644
--- a/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/ini-hl.xml
+++ b/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/ini-hl.xml
@@ -4,7 +4,7 @@
 Syntax highlighting definition for ini files
 
 xslthl - XSLT Syntax Highlighting
-http://sourceforge.net/projects/xslthl/
+https://sourceforge.net/projects/xslthl/
 Copyright (C) 2005-2008 Michal Molhanec, Jirka Kosek, Michiel Hendriks
 
 This software is provided 'as-is', without any express or implied
diff --git a/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/java-hl.xml b/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/java-hl.xml
index f7bb16414..4fe3c1fec 100644
--- a/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/java-hl.xml
+++ b/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/java-hl.xml
@@ -4,7 +4,7 @@
 Syntax highlighting definition for Java
 
 xslthl - XSLT Syntax Highlighting
-http://sourceforge.net/projects/xslthl/
+https://sourceforge.net/projects/xslthl/
 Copyright (C) 2005-2008 Michal Molhanec, Jirka Kosek, Michiel Hendriks
 
 This software is provided 'as-is', without any express or implied
diff --git a/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/javascript-hl.xml b/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/javascript-hl.xml
index 99b8a71e9..91620401f 100644
--- a/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/javascript-hl.xml
+++ b/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/javascript-hl.xml
@@ -4,7 +4,7 @@
 Syntax highlighting definition for JavaScript
 
 xslthl - XSLT Syntax Highlighting
-http://sourceforge.net/projects/xslthl/
+https://sourceforge.net/projects/xslthl/
 Copyright (C) 2005-2008 Michal Molhanec, Jirka Kosek, Michiel Hendriks
 
 This software is provided 'as-is', without any express or implied
diff --git a/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/perl-hl.xml b/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/perl-hl.xml
index 73d71cc02..c8a4d5902 100644
--- a/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/perl-hl.xml
+++ b/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/perl-hl.xml
@@ -4,7 +4,7 @@
 Syntax highlighting definition for Perl
 
 xslthl - XSLT Syntax Highlighting
-http://sourceforge.net/projects/xslthl/
+https://sourceforge.net/projects/xslthl/
 Copyright (C) 2005-2008 Michal Molhanec, Jirka Kosek, Michiel Hendriks
 
 This software is provided 'as-is', without any express or implied
diff --git a/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/php-hl.xml b/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/php-hl.xml
index 1da25b8cc..3ea157873 100644
--- a/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/php-hl.xml
+++ b/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/php-hl.xml
@@ -4,7 +4,7 @@
 Syntax highlighting definition for PHP
 
 xslthl - XSLT Syntax Highlighting
-http://sourceforge.net/projects/xslthl/
+https://sourceforge.net/projects/xslthl/
 Copyright (C) 2005-2008 Michal Molhanec, Jirka Kosek, Michiel Hendriks
 
 This software is provided 'as-is', without any express or implied
diff --git a/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/properties-hl.xml b/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/properties-hl.xml
index 775f2f13e..8205aac32 100644
--- a/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/properties-hl.xml
+++ b/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/properties-hl.xml
@@ -4,7 +4,7 @@
 Syntax highlighting definition for Java
 
 xslthl - XSLT Syntax Highlighting
-http://sourceforge.net/projects/xslthl/
+https://sourceforge.net/projects/xslthl/
 Copyright (C) 2005-2008 Michal Molhanec, Jirka Kosek, Michiel Hendriks
 
 This software is provided 'as-is', without any express or implied
diff --git a/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/python-hl.xml b/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/python-hl.xml
index a46744323..72bf0dbb1 100644
--- a/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/python-hl.xml
+++ b/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/python-hl.xml
@@ -4,7 +4,7 @@
 Syntax highlighting definition for Python
 
 xslthl - XSLT Syntax Highlighting
-http://sourceforge.net/projects/xslthl/
+https://sourceforge.net/projects/xslthl/
 Copyright (C) 2005-2008 Michal Molhanec, Jirka Kosek, Michiel Hendriks
 
 This software is provided 'as-is', without any express or implied
diff --git a/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/ruby-hl.xml b/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/ruby-hl.xml
index d105640e8..a2cee724a 100644
--- a/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/ruby-hl.xml
+++ b/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/ruby-hl.xml
@@ -4,7 +4,7 @@
 Syntax highlighting definition for Ruby
 
 xslthl - XSLT Syntax Highlighting
-http://sourceforge.net/projects/xslthl/
+https://sourceforge.net/projects/xslthl/
 Copyright (C) 2005-2008 Michal Molhanec, Jirka Kosek, Michiel Hendriks
 
 This software is provided 'as-is', without any express or implied
diff --git a/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/sql2003-hl.xml b/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/sql2003-hl.xml
index ac1d5d048..65c08a369 100644
--- a/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/sql2003-hl.xml
+++ b/spring-cloud-stream-core-docs/src/main/docbook/xsl/xslthl/sql2003-hl.xml
@@ -4,7 +4,7 @@
 Syntax highlighting definition for SQL:1999
 
 xslthl - XSLT Syntax Highlighting
-http://sourceforge.net/projects/xslthl/
+https://sourceforge.net/projects/xslthl/
 Copyright (C) 2012 Michiel Hendriks, Martin Hujer, k42b3
 
 This software is provided 'as-is', without any express or implied
diff --git a/spring-cloud-stream-tools/src/main/resources/checkstyle-suppressions.xml b/spring-cloud-stream-tools/src/main/resources/checkstyle-suppressions.xml
index a5be3bd96..a80ca62fd 100644
--- a/spring-cloud-stream-tools/src/main/resources/checkstyle-suppressions.xml
+++ b/spring-cloud-stream-tools/src/main/resources/checkstyle-suppressions.xml
@@ -1,7 +1,7 @@
 <?xml version="1.0"?>
 <!DOCTYPE suppressions PUBLIC
         "-//Puppy Crawl//DTD Suppressions 1.1//EN"
-        "http://www.puppycrawl.com/dtds/suppressions_1_1.dtd">
+        "https://www.puppycrawl.com/dtds/suppressions_1_1.dtd">
 <suppressions>
     <suppress files="[\\/]src[\\/]main[\\/]java[\\/]org[\\/]springframework[\\/]cloud[\\/]stream[\\/]reactive[\\/]reactor[\\/]core[\\/]scheduler[\\/]" checks=".*" />
     <suppress files="[\\/]src[\\/]test[\\/]java[\\/]" checks="AvoidStaticImport" />
diff --git a/spring-cloud-stream-tools/src/main/resources/checkstyle.xml b/spring-cloud-stream-tools/src/main/resources/checkstyle.xml
index 283e4e2c9..e42080dfa 100644
--- a/spring-cloud-stream-tools/src/main/resources/checkstyle.xml
+++ b/spring-cloud-stream-tools/src/main/resources/checkstyle.xml
@@ -1,7 +1,7 @@
 <?xml version="1.0"?>
 <!DOCTYPE module PUBLIC
         "-//Puppy Crawl//DTD Check Configuration 1.3//EN"
-        "http://www.puppycrawl.com/dtds/configuration_1_3.dtd">
+        "https://www.puppycrawl.com/dtds/configuration_1_3.dtd">
 <module name="Checker">
     <!-- Root Checks -->
     <module name="RegexpHeader">