workflow: add Checkstyle for code quality checks

Author: WhatDamon

build.gradle.kts

@@ -1,7 +1,8 @@
 plugins {
-	id("net.fabricmc.fabric-loom-remap")
-	`maven-publish`
-}
+ 	id("net.fabricmc.fabric-loom-remap")
+ 	`maven-publish`
+ 	checkstyle
+ }
 
 version = providers.gradleProperty("mod_version").get()
 group = providers.gradleProperty("maven_group").get()
@@ -88,8 +89,27 @@ tasks.jar {
 }
 
 tasks.test {
-	useJUnitPlatform()
-}
+ 	useJUnitPlatform()
+ }
+
+checkstyle {
+ 	toolVersion = "10.17.0"
+ 	configFile = file("checkstyle.xml")
+ }
+
+tasks.checkstyleMain {
+ 	reports {
+ 		xml.required = true
+ 		html.required = true
+ 	}
+ }
+
+tasks.checkstyleTest {
+ 	reports {
+ 		xml.required = true
+ 		html.required = true
+ 	}
+ }
 
 // configure the maven publication
 publishing {

checkstyle.xml

@@ -0,0 +1,70 @@
+<?xml version="1.0"?>
+<!DOCTYPE module PUBLIC
+    "-//Checkstyle//DTD Checkstyle Configuration 1.3//EN"
+    "https://checkstyle.org/dtds/configuration_1_3.dtd">
+
+<module name="Checker">
+    <property name="severity" value="warning"/>
+    <property name="fileExtensions" value="java"/>
+
+    <module name="TreeWalker">
+        <module name="NeedBraces">
+            <property name="tokens" value="LITERAL_DO, LITERAL_ELSE, LITERAL_FOR, LITERAL_IF, LITERAL_WHILE"/>
+        </module>
+
+        <module name="LeftCurly"/>
+        <module name="RightCurly"/>
+
+        <module name="WhitespaceAfter">
+            <property name="tokens" value="COMMA, SEMI"/>
+        </module>
+
+        <module name="WhitespaceAround">
+            <property name="allowEmptyConstructors" value="true"/>
+            <property name="allowEmptyLambdas" value="true"/>
+            <property name="allowEmptyMethods" value="true"/>
+            <property name="allowEmptyTypes" value="true"/>
+            <property name="allowEmptyLoops" value="true"/>
+        </module>
+
+        <module name="GenericWhitespace"/>
+
+        <module name="ParenPad"/>
+
+        <module name="NoLineWrap"/>
+
+        <module name="EmptyBlock">
+            <property name="option" value="TEXT"/>
+            <property name="tokens" value="LITERAL_TRY, LITERAL_FINALLY, LITERAL_IF, LITERAL_ELSE, LITERAL_SWITCH"/>
+        </module>
+
+        <module name="ArrayTypeStyle"/>
+        <module name="UpperEll"/>
+
+        <module name="FallThrough"/>
+
+        <module name="ModifierOrder"/>
+
+        <module name="MissingSwitchDefault"/>
+
+        <module name="PackageName">
+            <property name="format" value="^[a-z]+(\.[a-z][a-z0-9]*)*$"/>
+        </module>
+
+        <module name="TypeName">
+            <property name="format" value="^[A-Z][a-zA-Z0-9_]*$"/>
+        </module>
+
+        <module name="MemberName">
+            <property name="format" value="^[a-z][a-zA-Z0-9]*$"/>
+        </module>
+
+        <module name="ParameterName">
+            <property name="format" value="^[a-z]([a-zA-Z0-9]*)?$"/>
+        </module>
+
+        <module name="MethodName">
+            <property name="format" value="^[a-z][a-zA-Z0-9_]*$"/>
+        </module>
+    </module>
+</module>