Cleaned up the StatusUpdate.java

src/main/java/com/javadiscord/javabot/Bot.java

@@ -3,20 +3,24 @@
 import com.jagrosh.jdautilities.command.Command;
 import com.jagrosh.jdautilities.command.CommandClient;
 import com.jagrosh.jdautilities.command.CommandClientBuilder;
+import com.javadiscord.javabot.commands.other.Version;
 import com.javadiscord.javabot.events.*;
 import com.javadiscord.javabot.properties.MultiProperties;
 import net.dv8tion.jda.api.JDA;
 import net.dv8tion.jda.api.JDABuilder;
 import net.dv8tion.jda.api.OnlineStatus;
+import net.dv8tion.jda.api.entities.Activity;
 import net.dv8tion.jda.api.requests.GatewayIntent;
 import net.dv8tion.jda.api.utils.MemberCachePolicy;
 import net.dv8tion.jda.api.utils.cache.CacheFlag;
 import org.reflections.Reflections;
 
 import java.lang.reflect.Modifier;
 import java.nio.file.Path;
+import java.util.List;
 import java.util.Objects;
 import java.util.Properties;
+import java.util.concurrent.TimeUnit;
 
 
 public class Bot {
@@ -48,7 +52,7 @@ public static void main(String[] args) throws Exception {
         jda.addEventListener(new UserJoin());
         jda.addEventListener(new UserLeave());
         jda.addEventListener(new Startup());
-        jda.addEventListener(new StatusUpdate());
+        jda.addEventListener(PresenceUpdater.standardActivities());
         jda.addEventListener(new ReactionListener());
         jda.addEventListener(new SuggestionListener());
         jda.addEventListener(new CstmCmdListener());

src/main/java/com/javadiscord/javabot/PresenceUpdater.java

@@ -0,0 +1,105 @@
+package com.javadiscord.javabot;
+
+import com.javadiscord.javabot.commands.other.Version;
+import net.dv8tion.jda.api.JDA;
+import net.dv8tion.jda.api.OnlineStatus;
+import net.dv8tion.jda.api.entities.Activity;
+import net.dv8tion.jda.api.events.ReadyEvent;
+import net.dv8tion.jda.api.hooks.ListenerAdapter;
+
+import javax.annotation.Nonnull;
+import java.util.List;
+import java.util.concurrent.CopyOnWriteArrayList;
+import java.util.concurrent.Executors;
+import java.util.concurrent.ScheduledExecutorService;
+import java.util.concurrent.TimeUnit;
+import java.util.function.Function;
+
+/**
+ * Periodically updates the bot's Discord presence by cycling through a list of
+ * activities. Also sets the bot to {@link OnlineStatus#DO_NOT_DISTURB} if it's
+ * not set like that already.
+ * <p>
+ *     This updater should be added as an event listener to the bot, so that it
+ *     will automatically begin operation when the bot gives the ready event.
+ * </p>
+ */
+public class PresenceUpdater extends ListenerAdapter {
+    /**
+     * The executor that is responsible for the scheduled updates of the bot's
+     * presence data.
+     */
+    private final ScheduledExecutorService threadPool = Executors.newSingleThreadScheduledExecutor();
+
+    /**
+     * A list of functions that take a reference to the bot's JDA client, and
+     * produce an {@link Activity} that should be displayed.
+     */
+    private final List<Function<JDA, Activity>> activities;
+
+    /**
+     * The index of the currently active activity.
+     */
+    private int currentActivityIndex = 0;
+
+    /**
+     * The amount of time the updater should wait before updating the activity.
+     */
+    private final long delay;
+
+    /**
+     * The unit of time that {@link PresenceUpdater#delay} is counted in.
+     */
+    private final TimeUnit delayUnit;
+
+    /**
+     * A reference to the bot's JDA client object. This is set as soon as the
+     * bot is ready, and so it will never be null when passed to a function.
+     */
+    private JDA jda;
+
+    /**
+     * Constructs an updater using a list of activities, and a delay and time
+     * unit to describe how frequently to cycle through them.
+     * @param activities The list of activity-producing functions.
+     * @param delay The amount of time the updater should wait before updating the activity.
+     * @param delayUnit The unit of time that {@link PresenceUpdater#delay} is counted in.
+     */
+    public PresenceUpdater(List<Function<JDA, Activity>> activities, long delay, TimeUnit delayUnit) {
+        this.activities = new CopyOnWriteArrayList<>(activities);
+        this.delay = delay;
+        this.delayUnit = delayUnit;
+    }
+
+    /**
+     * Called when the Discord bot is ready. This triggers the start of the
+     * scheduled updating of the bot's activities.
+     * @param event The ready event that's sent. Notably, contains a reference
+     *              to the bot's {@link JDA} client.
+     */
+    @Override
+    public void onReady(@Nonnull ReadyEvent event) {
+        this.jda = event.getJDA();
+        threadPool.scheduleWithFixedDelay(() -> {
+            if (this.jda.getPresence().getStatus() != OnlineStatus.DO_NOT_DISTURB) {
+                this.jda.getPresence().setStatus(OnlineStatus.DO_NOT_DISTURB);
+            }
+            if (currentActivityIndex >= this.activities.size()) currentActivityIndex = 0;
+            if (this.activities.size() > 0) {
+                this.jda.getPresence().setActivity(this.activities.get(currentActivityIndex++).apply(this.jda));
+            }
+        }, 0, this.delay, this.delayUnit);
+    }
+
+    /**
+     * @return A pre-built implementation of the {@link PresenceUpdater} that
+     * has all the necessary properties defined to reasonable defaults.
+     */
+    public static PresenceUpdater standardActivities() {
+        return new PresenceUpdater(List.of(
+            jda -> Activity.watching("javadiscord.net" + " | " + new Version().getVersion()),
+            jda -> Activity.listening(jda.getGuilds().get(0).getMemberCount() + " members" + " | " + new Version().getVersion()),
+            jda -> Activity.watching("/help" + " | " + new Version().getVersion())
+        ), 35, TimeUnit.SECONDS);
+    }
+}