Add documentation on all public interfaces

build.gradle

@@ -1,6 +1,7 @@
 plugins {
     id "java"
     id "org.jetbrains.kotlin.jvm" version "1.7.10"
+    id 'org.jetbrains.dokka' version "1.7.10"
     id 'maven-publish'
     id "com.github.johnrengelman.shadow" version "7.1.2"
 }
@@ -97,8 +98,14 @@ compileTestKotlin {
     }
 }
 
-if (file("local.gradle").exists()) {
-    apply from: "local.gradle"
+dokkaHtml {
+    outputDirectory.set(file("${buildDir}/dokka"))
+}
+
+javadocJar {
+    archiveClassifier.set("javadoc")
+    dependsOn("dokkaHtml")
+    from("$buildDir/dokka")
 }
 
 shadowJar {
@@ -135,3 +142,7 @@ publishing {
         }
     }
 }
+
+if (file("local.gradle").exists()) {
+    apply from: "local.gradle"
+}

src/main/java/dev/mikchan/mcnp/maintenance/MaintenanceModePlugin.kt

@@ -10,6 +10,9 @@ import org.bstats.bukkit.Metrics
 import org.bukkit.event.HandlerList
 import org.bukkit.plugin.java.JavaPlugin
 
+/**
+ * The main plugin class
+ */
 @Suppress("unused")
 class MaintenanceModePlugin : JavaPlugin(), IConfigListener {
     companion object {

src/main/java/dev/mikchan/mcnp/maintenance/config/IConfig.kt

@@ -1,11 +1,40 @@
 package dev.mikchan.mcnp.maintenance.config
 
+/**
+ * The config interface
+ */
 interface IConfig {
+    /**
+     * Is the maintenance mode enabled
+     */
     var enabled: Boolean
+
+    /**
+     * The message player sees when tries to connect to the server, while [enabled] is `true`
+     */
     val kickMessage: String
+
+    /**
+     * Should the server also display a custom MOTD when pinged while in maintenance mode
+     */
     val enableCustomMotd: Boolean
+
+    /**
+     * The MOTD which is displayed if [enabled] and [enableCustomMotd] are `true`
+     */
     val customMotd: String
 
+    /**
+     * Subscribes a new config listener.
+     *
+     * Whenever config is updated, [IConfigListener.handleUpdate] will be called on every listener.
+     *
+     * @param listener A listener to subscribe.
+     */
     fun subscribe(listener: IConfigListener)
+
+    /**
+     * Reloads the config from the file.
+     */
     fun reload()
 }

src/main/java/dev/mikchan/mcnp/maintenance/config/IConfigListener.kt

@@ -1,5 +1,15 @@
 package dev.mikchan.mcnp.maintenance.config
 
+/**
+ * A config listener interface.
+ *
+ * Listens to config updates.
+ */
 interface IConfigListener {
+    /**
+     * This method is called whenever config is updated.
+     *
+     * @param config A new state of config.
+     */
     fun handleUpdate(config: IConfig)
 }