diff --git a/checkstyle.xml b/checkstyle.xml
index 5c7f6a5d5..12feab88b 100644
--- a/checkstyle.xml
+++ b/checkstyle.xml
@@ -1,43 +1,42 @@
 <?xml version="1.0"?>
 <!DOCTYPE module PUBLIC
-          "-//Checkstyle//DTD Checkstyle Configuration 1.3//EN"
-          "https://checkstyle.org/dtds/configuration_1_3.dtd">
+        "-//Checkstyle//DTD Checkstyle Configuration 1.3//EN"
+        "https://checkstyle.org/dtds/configuration_1_3.dtd">
 
 <module name="Checker">
-    <!-- See http://checkstyle.sourceforge.net/config_misc.html#NewlineAtEndOfFile -->
+    <!-- See https://checkstyle.org/checks/misc/newlineatendoffile.html#NewlineAtEndOfFile -->
     <module name="NewlineAtEndOfFile">
         <property name="lineSeparator" value="lf_cr_crlf"/>
     </module>
 
-    <!-- See http://checkstyle.sourceforge.net/config_whitespace.html -->
+    <!-- See https://checkstyle.org/checks/whitespace/filetabcharacter.html#FileTabCharacter -->
     <module name="FileTabCharacter"/>
 
-    <!-- See http://checkstyle.sourceforge.net/config_misc.html -->
+    <!-- See https://checkstyle.org/checks/regexp/regexpsingleline.html -->
     <module name="RegexpSingleline">
         <property name="format" value="\s+$"/>
         <property name="minimum" value="0"/>
         <property name="maximum" value="0"/>
         <property name="message" value="Line has trailing spaces."/>
     </module>
+    <!-- See SPIGOT-7676: Enforce Locale, to prevent issues with turkish 'I' and similar -->
+    <module name="RegexpSingleline">
+        <property name="format" value="\.toUpperCase\(\s*\)"/>
+        <property name="message" value="Use toUpperCase(Locale.ROOT) instead of toUpperCase()"/>
+    </module>
+    <module name="RegexpSingleline">
+        <property name="format" value="\.toLowerCase\(\s*\)"/>
+        <property name="message" value="Use toLowerCase(Locale.ROOT) instead of toLowerCase()"/>
+    </module>
 
-    <!-- See http://checkstyle.sourceforge.net/config_filters.html -->
+    <!-- See https://checkstyle.org/filters/suppressionsinglefilter.html#SuppressionSingleFilter -->
     <module name="SuppressionSingleFilter">
         <property name="checks" value="UnusedImports"/>
         <property name="files" value=".*[/\\]net[/\\]minecraft[/\\].*"/>
     </module>
 
-    <!-- See SPIGOT-7676: Enforce Locale, to prevent issues with turkish 'I' and similar -->
-    <module name="RegexpSingleline">
-        <property name="format" value="\.toUpperCase\(\s*\)" />
-        <property name="message" value="Use toUpperCase(Locale.ROOT) instead of toUpperCase()" />
-    </module>
-    <module name="RegexpSingleline">
-        <property name="format" value="\.toLowerCase\(\s*\)" />
-        <property name="message" value="Use toLowerCase(Locale.ROOT) instead of toLowerCase()" />
-    </module>
-
     <module name="TreeWalker">
-        <!-- See https://checkstyle.org/config_javadoc.html -->
+        <!-- See https://checkstyle.org/checks/javadoc/index.html -->
         <module name="AtclauseOrder"/>
         <module name="InvalidJavadocPosition"/>
         <module name="JavadocBlockTagLocation"/>
@@ -47,7 +46,7 @@
         <module name="MissingJavadocPackage"/>
         <!--<module name="NonEmptyAtclauseDescription"/>-->
 
-        <!-- See http://checkstyle.sourceforge.net/config_filters.html -->
+        <!-- See https://checkstyle.org/filters/index.html -->
         <module name="SuppressionCommentFilter"/>
         <module name="SuppressionCommentFilter">
             <property name="offCommentFormat" value="CraftBukkit start"/>
@@ -57,7 +56,7 @@
             <property name="commentFormat" value="CraftBukkit"/>
         </module>
 
-        <!-- See http://checkstyle.sourceforge.net/config_imports.html -->
+        <!-- See https://checkstyle.org/checks/imports/index.html -->
         <module name="AvoidStarImport">
             <property name="allowStaticMemberImports" value="true"/>
         </module>
@@ -70,7 +69,7 @@
         <module name="RedundantImport"/>
         <module name="UnusedImports"/>
 
-        <!-- See https://checkstyle.org/config_whitespace.html -->
+        <!-- See https://checkstyle.org/checks/whitespace/index.html -->
         <module name="GenericWhitespace"/>
         <module name="MethodParamPad"/>
         <module name="NoLineWrap"/>
@@ -90,19 +89,19 @@
             <property name="allowEmptyTypes" value="true"/>
         </module>
 
-        <!-- See http://checkstyle.sourceforge.net/config_modifiers.html -->
+        <!-- See https://checkstyle.org/checks/modifier/index.html -->
         <module name="ModifierOrder"/>
 
-        <!-- See https://checkstyle.org/config_blocks.html -->
+        <!-- See https://checkstyle.org/checks/blocks/index.html -->
         <!--<module name="AvoidNestedBlocks"/>-->
         <module name="LeftCurly"/>
         <module name="RightCurly"/>
 
-        <!-- See http://checkstyle.sourceforge.net/config_design.html -->
+        <!-- See https://checkstyle.org/checks/design/index.html -->
         <!--<module name="FinalClass"/>-->
         <!--<module name="InterfaceIsType"/>-->
 
-        <!-- See http://checkstyle.sourceforge.net/config_misc.html -->
+        <!-- See https://checkstyle.org/checks/misc/index.html -->
         <module name="ArrayTypeStyle"/>
         <module name="UpperEll"/>
     </module>