From a6e5e58bae1e1b5204d4f7445ebc37ff2047f767 Mon Sep 17 00:00:00 2001
From: Daniel Heid <mail@daniel-heid.de>
Date: Thu, 2 Nov 2023 19:30:23 +0100
Subject: [PATCH] Adapt checkstyle configuration (#65)

---
 checkstyle.xml | 62 ++++++++++++++++++++++++++++++--------------------
 pom.xml        | 11 ++-------
 2 files changed, 39 insertions(+), 34 deletions(-)

diff --git a/checkstyle.xml b/checkstyle.xml
index 8955e917..c71071b6 100644
--- a/checkstyle.xml
+++ b/checkstyle.xml
@@ -2,28 +2,50 @@
 <!DOCTYPE module PUBLIC
   "-//Checkstyle//DTD Checkstyle Configuration 1.3//EN"
   "https://checkstyle.org/dtds/configuration_1_3.dtd">
-<module name="Checker">
-  <module name="SuppressWarningsFilter"/>
+
+<!--
+    Checkstyle configuration that checks the Google coding conventions from Google Java Style
+    that can be found at https://google.github.io/styleguide/javaguide.html
+
+    Checkstyle is very configurable. Be sure to read the documentation at
+    http://checkstyle.org (or in your downloaded distribution).
+
+    To completely disable a check, just comment it out or delete it from the file.
+    To suppress certain violations please review suppression filters.
+
+    Authors: Max Vetrenko, Ruslan Diachenko, Roman Ivanov.
+ -->
+
+<module name = "Checker">
   <property name="charset" value="UTF-8"/>
+
   <property name="severity" value="warning"/>
+
   <property name="fileExtensions" value="java, properties, xml"/>
+  <!-- Excludes all 'module-info.java' files              -->
+  <!-- See https://checkstyle.org/config_filefilters.html -->
   <module name="BeforeExecutionExclusionFileFilter">
     <property name="fileNamePattern" value="module\-info\.java$"/>
   </module>
+  <!-- https://checkstyle.org/config_filters.html#SuppressionFilter -->
   <module name="SuppressionFilter">
     <property name="file" value="${org.checkstyle.google.suppressionfilter.config}"
-              default="checkstyle-suppressions.xml"/>
+              default="checkstyle-suppressions.xml" />
     <property name="optional" value="true"/>
   </module>
+
+  <!-- Checks for whitespace                               -->
+  <!-- See http://checkstyle.org/config_whitespace.html -->
   <module name="FileTabCharacter">
     <property name="eachLine" value="true"/>
   </module>
+
   <module name="LineLength">
     <property name="fileExtensions" value="java"/>
     <property name="max" value="120"/>
-    <property name="ignorePattern"
-              value="^package.*|^import.*|a href|href|http://|https://|ftp://|idsite.*|Exception\(.*"/>
+    <property name="ignorePattern" value="^package.*|^import.*|a href|href|http://|https://|ftp://|Exception\(.*|idsite=.*"/>
   </module>
+
   <module name="TreeWalker">
     <module name="OuterTypeFilename"/>
     <module name="IllegalTokenText">
@@ -72,19 +94,18 @@
       <property name="tokens"
                 value="CLASS_DEF, METHOD_DEF, CTOR_DEF, LITERAL_FOR, LITERAL_WHILE, STATIC_INIT,
                     INSTANCE_INIT, ANNOTATION_DEF, ENUM_DEF, INTERFACE_DEF, RECORD_DEF,
-                    COMPACT_CTOR_DEF, LITERAL_SWITCH"/>
+                    COMPACT_CTOR_DEF"/>
     </module>
     <module name="SuppressionXpathSingleFilter">
+      <!-- suppresion is required till https://github.com/checkstyle/checkstyle/issues/7541 -->
       <property name="id" value="RightCurlyAlone"/>
       <property name="query" value="//RCURLY[parent::SLIST[count(./*)=1]
                                      or preceding-sibling::*[last()][self::LCURLY]]"/>
     </module>
     <module name="WhitespaceAfter">
       <property name="tokens"
-                value="COMMA, SEMI, TYPECAST, LITERAL_IF, LITERAL_ELSE, LITERAL_RETURN,
-                    LITERAL_WHILE, LITERAL_DO, LITERAL_FOR, LITERAL_FINALLY, DO_WHILE, ELLIPSIS,
-                    LITERAL_SWITCH, LITERAL_SYNCHRONIZED, LITERAL_TRY, LITERAL_CATCH, LAMBDA,
-                    LITERAL_YIELD, LITERAL_CASE"/>
+                value="COMMA, SEMI, TYPECAST, LITERAL_IF, LITERAL_ELSE,
+                    LITERAL_WHILE, LITERAL_DO, LITERAL_FOR, DO_WHILE"/>
     </module>
     <module name="WhitespaceAround">
       <property name="allowEmptyConstructors" value="true"/>
@@ -102,8 +123,7 @@
                     NOT_EQUAL, PLUS, PLUS_ASSIGN, QUESTION, RCURLY, SL, SLIST, SL_ASSIGN, SR,
                     SR_ASSIGN, STAR, STAR_ASSIGN, LITERAL_ASSERT, TYPE_EXTENSION_AND"/>
       <message key="ws.notFollowed"
-               value="WhitespaceAround: ''{0}'' is not followed by whitespace. Empty blocks
-               may only be represented as '{}' when not part of a multi-block statement (4.1.3)"/>
+               value="WhitespaceAround: ''{0}'' is not followed by whitespace. Empty blocks may only be represented as '{}' when not part of a multi-block statement (4.1.3)"/>
       <message key="ws.notPreceded"
                value="WhitespaceAround: ''{0}'' is not preceded with whitespace."/>
     </module>
@@ -132,11 +152,13 @@
       <property name="option" value="EOL"/>
     </module>
     <module name="SeparatorWrap">
+      <!-- ELLIPSIS is EOL until https://github.com/google/styleguide/issues/259 -->
       <property name="id" value="SeparatorWrapEllipsis"/>
       <property name="tokens" value="ELLIPSIS"/>
       <property name="option" value="EOL"/>
     </module>
     <module name="SeparatorWrap">
+      <!-- ARRAY_DECLARATOR is EOL until https://github.com/google/styleguide/issues/258 -->
       <property name="id" value="SeparatorWrapArrayDeclarator"/>
       <property name="tokens" value="ARRAY_DECLARATOR"/>
       <property name="option" value="EOL"/>
@@ -315,7 +337,7 @@
       <property name="excludeScope" value="nothing"/>
     </module>
     <module name="MethodName">
-      <property name="format" value="^[a-z][a-z0-9]\w*$"/>
+      <property name="format" value="^[a-z][a-z0-9][a-zA-Z0-9_]*$"/>
       <message key="name.invalidPattern"
                value="Method name ''{0}'' must match pattern ''{1}''."/>
     </module>
@@ -326,21 +348,11 @@
     <module name="CommentsIndentation">
       <property name="tokens" value="SINGLE_LINE_COMMENT, BLOCK_COMMENT_BEGIN"/>
     </module>
+    <!-- https://checkstyle.org/config_filters.html#SuppressionXpathFilter -->
     <module name="SuppressionXpathFilter">
       <property name="file" value="${org.checkstyle.google.suppressionxpathfilter.config}"
-                default="checkstyle-xpath-suppressions.xml"/>
+                default="checkstyle-xpath-suppressions.xml" />
       <property name="optional" value="true"/>
     </module>
-    <module name="SuppressWarningsHolder"/>
-    <module name="SuppressionCommentFilter">
-      <property name="offCommentFormat" value="CHECKSTYLE.OFF\: ([\w\|]+)"/>
-      <property name="onCommentFormat" value="CHECKSTYLE.ON\: ([\w\|]+)"/>
-      <property name="checkFormat" value="$1"/>
-    </module>
-    <module name="SuppressWithNearbyCommentFilter">
-      <property name="commentFormat" value="CHECKSTYLE.SUPPRESS\: ([\w\|]+)"/>
-      <property name="checkFormat" value="$1"/>
-      <property name="influenceFormat" value="1"/>
-    </module>
   </module>
 </module>
diff --git a/pom.xml b/pom.xml
index bb5d4c91..001436ed 100644
--- a/pom.xml
+++ b/pom.xml
@@ -247,12 +247,12 @@
                     <limit>
                       <counter>LINE</counter>
                       <value>COVEREDRATIO</value>
-                      <minimum>1.0</minimum>
+                      <minimum>0.9</minimum>
                     </limit>
                     <limit>
                       <counter>BRANCH</counter>
                       <value>COVEREDRATIO</value>
-                      <minimum>1.0</minimum>
+                      <minimum>0.9</minimum>
                     </limit>
                   </limits>
                 </rule>
@@ -265,13 +265,6 @@
         <groupId>org.apache.maven.plugins</groupId>
         <artifactId>maven-checkstyle-plugin</artifactId>
         <version>3.3.1</version>
-        <dependencies>
-          <dependency>
-            <groupId>com.puppycrawl.tools</groupId>
-            <artifactId>checkstyle</artifactId>
-            <version>10.12.4</version>
-          </dependency>
-        </dependencies>
         <configuration>
           <violationSeverity>warning</violationSeverity>
           <configLocation>checkstyle.xml</configLocation>