diff --git a/docs/src/main/docbook/xsl/xslthl-config.xml b/docs/src/main/docbook/xsl/xslthl-config.xml
index 1dce4071..5aac4493 100644
--- a/docs/src/main/docbook/xsl/xslthl-config.xml
+++ b/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/docs/src/main/docbook/xsl/xslthl/bourne-hl.xml b/docs/src/main/docbook/xsl/xslthl/bourne-hl.xml
index 518fdb86..b98d756e 100644
--- a/docs/src/main/docbook/xsl/xslthl/bourne-hl.xml
+++ b/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/docs/src/main/docbook/xsl/xslthl/c-hl.xml b/docs/src/main/docbook/xsl/xslthl/c-hl.xml
index 0c994db7..7943634f 100644
--- a/docs/src/main/docbook/xsl/xslthl/c-hl.xml
+++ b/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/docs/src/main/docbook/xsl/xslthl/cpp-hl.xml b/docs/src/main/docbook/xsl/xslthl/cpp-hl.xml
index a9f7d0de..b0789e9d 100644
--- a/docs/src/main/docbook/xsl/xslthl/cpp-hl.xml
+++ b/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/docs/src/main/docbook/xsl/xslthl/csharp-hl.xml b/docs/src/main/docbook/xsl/xslthl/csharp-hl.xml
index e21a1258..59ce58e7 100644
--- a/docs/src/main/docbook/xsl/xslthl/csharp-hl.xml
+++ b/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/docs/src/main/docbook/xsl/xslthl/css-hl.xml b/docs/src/main/docbook/xsl/xslthl/css-hl.xml
index e5a14286..b75f1e2c 100644
--- a/docs/src/main/docbook/xsl/xslthl/css-hl.xml
+++ b/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/docs/src/main/docbook/xsl/xslthl/html-hl.xml b/docs/src/main/docbook/xsl/xslthl/html-hl.xml
index fd48f118..82d04d3f 100644
--- a/docs/src/main/docbook/xsl/xslthl/html-hl.xml
+++ b/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/docs/src/main/docbook/xsl/xslthl/ini-hl.xml b/docs/src/main/docbook/xsl/xslthl/ini-hl.xml
index 34c10363..6bd60b3e 100644
--- a/docs/src/main/docbook/xsl/xslthl/ini-hl.xml
+++ b/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/docs/src/main/docbook/xsl/xslthl/java-hl.xml b/docs/src/main/docbook/xsl/xslthl/java-hl.xml
index 96ef3da7..d39f7dad 100644
--- a/docs/src/main/docbook/xsl/xslthl/java-hl.xml
+++ b/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/docs/src/main/docbook/xsl/xslthl/javascript-hl.xml b/docs/src/main/docbook/xsl/xslthl/javascript-hl.xml
index f74807f3..85710a0f 100644
--- a/docs/src/main/docbook/xsl/xslthl/javascript-hl.xml
+++ b/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/docs/src/main/docbook/xsl/xslthl/perl-hl.xml b/docs/src/main/docbook/xsl/xslthl/perl-hl.xml
index adf7b094..65188210 100644
--- a/docs/src/main/docbook/xsl/xslthl/perl-hl.xml
+++ b/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/docs/src/main/docbook/xsl/xslthl/php-hl.xml b/docs/src/main/docbook/xsl/xslthl/php-hl.xml
index 1060ae4d..72a9bd40 100644
--- a/docs/src/main/docbook/xsl/xslthl/php-hl.xml
+++ b/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/docs/src/main/docbook/xsl/xslthl/properties-hl.xml b/docs/src/main/docbook/xsl/xslthl/properties-hl.xml
index 775f2f13..8205aac3 100644
--- a/docs/src/main/docbook/xsl/xslthl/properties-hl.xml
+++ b/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/docs/src/main/docbook/xsl/xslthl/python-hl.xml b/docs/src/main/docbook/xsl/xslthl/python-hl.xml
index fd6db57b..fa1aeb6a 100644
--- a/docs/src/main/docbook/xsl/xslthl/python-hl.xml
+++ b/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/docs/src/main/docbook/xsl/xslthl/ruby-hl.xml b/docs/src/main/docbook/xsl/xslthl/ruby-hl.xml
index 5bf3473d..bcef913b 100644
--- a/docs/src/main/docbook/xsl/xslthl/ruby-hl.xml
+++ b/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/docs/src/main/docbook/xsl/xslthl/sql2003-hl.xml b/docs/src/main/docbook/xsl/xslthl/sql2003-hl.xml
index bb561c64..85dcd031 100644
--- a/docs/src/main/docbook/xsl/xslthl/sql2003-hl.xml
+++ b/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-build-tools/src/checkstyle/checkstyle-suppressions.xml b/spring-cloud-build-tools/src/checkstyle/checkstyle-suppressions.xml
index 2c620df6..f5f67058 100644
--- a/spring-cloud-build-tools/src/checkstyle/checkstyle-suppressions.xml
+++ b/spring-cloud-build-tools/src/checkstyle/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[\\/]test[\\/](java|groovy)[\\/]"
 			  checks="(Javadoc*|HideUtility*)"/>
diff --git a/spring-cloud-build-tools/src/main/resources/checkstyle.xml b/spring-cloud-build-tools/src/main/resources/checkstyle.xml
index 84b99566..e140830d 100644
--- a/spring-cloud-build-tools/src/main/resources/checkstyle.xml
+++ b/spring-cloud-build-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="com.puppycrawl.tools.checkstyle.Checker">
 
 	<module name="SuppressionFilter">