Release v4.1

application/build.gradle

@@ -74,7 +74,7 @@ dependencies {
 
     implementation 'com.github.ben-manes.caffeine:caffeine:3.1.1'
 
-    testImplementation 'org.mockito:mockito-core:4.9.0'
+    testImplementation 'org.mockito:mockito-core:4.10.0'
     testImplementation 'org.junit.jupiter:junit-jupiter-api:5.9.0'
     testImplementation 'org.junit.jupiter:junit-jupiter-params:5.9.0'
     testRuntimeOnly 'org.junit.jupiter:junit-jupiter-engine:5.9.0'

application/src/main/java/org/togetherjava/tjbot/commands/bookmarks/LeftoverBookmarksListener.java

@@ -3,7 +3,6 @@
 import net.dv8tion.jda.api.events.guild.member.GuildMemberJoinEvent;
 import net.dv8tion.jda.api.events.guild.member.GuildMemberRemoveEvent;
 import net.dv8tion.jda.api.hooks.ListenerAdapter;
-import org.jetbrains.annotations.NotNull;
 
 import org.togetherjava.tjbot.commands.EventReceiver;
 
@@ -25,14 +24,14 @@ public LeftoverBookmarksListener(BookmarksSystem bookmarksSystem) {
     }
 
     @Override
-    public void onGuildMemberRemove(@NotNull GuildMemberRemoveEvent event) {
+    public void onGuildMemberRemove(GuildMemberRemoveEvent event) {
         long userID = event.getUser().getIdLong();
 
         bookmarksSystem.startDeletionPeriodForUser(userID);
     }
 
     @Override
-    public void onGuildMemberJoin(@NotNull GuildMemberJoinEvent event) {
+    public void onGuildMemberJoin(GuildMemberJoinEvent event) {
         long userID = event.getUser().getIdLong();
 
         bookmarksSystem.cancelDeletionPeriodForUser(userID);

application/src/main/java/org/togetherjava/tjbot/commands/help/HelpSystemHelper.java

@@ -32,9 +32,11 @@
 import java.io.InputStream;
 import java.util.*;
 import java.util.function.Consumer;
+import java.util.function.Function;
 import java.util.function.Predicate;
 import java.util.regex.Pattern;
 import java.util.stream.Collectors;
+import java.util.stream.IntStream;
 
 /**
  * Helper class offering certain methods used by the help system.
@@ -48,6 +50,11 @@ public final class HelpSystemHelper {
 
     private final Predicate<String> isHelpForumName;
     private final String helpForumPattern;
+    /**
+     * Compares categories by how common they are, ascending. I.e., the most uncommon or specific
+     * category comes first.
+     */
+    private final Comparator<ForumTag> byCategoryCommonnessAsc;
     private final Set<String> categories;
     private final Set<String> threadActivityTagNames;
     private final String categoryRoleSuffix;
@@ -66,9 +73,18 @@ public HelpSystemHelper(Config config, Database database) {
         helpForumPattern = helpConfig.getHelpForumPattern();
         isHelpForumName = Pattern.compile(helpForumPattern).asMatchPredicate();
 
-        categories = new HashSet<>(helpConfig.getCategories());
+        List<String> categoriesList = helpConfig.getCategories();
+        categories = new HashSet<>(categoriesList);
         categoryRoleSuffix = helpConfig.getCategoryRoleSuffix();
 
+        Map<String, Integer> categoryToCommonDesc = IntStream.range(0, categoriesList.size())
+            .boxed()
+            .collect(Collectors.toMap(categoriesList::get, Function.identity()));
+        byCategoryCommonnessAsc = Comparator
+            .<ForumTag>comparingInt(
+                    tag -> categoryToCommonDesc.getOrDefault(tag.getName(), categories.size()))
+            .reversed();
+
         threadActivityTagNames = Arrays.stream(ThreadActivity.values())
             .map(ThreadActivity::getTagName)
             .collect(Collectors.toSet());
@@ -97,10 +113,6 @@ private RestAction<Message> sendExplanationMessage(GuildMessageChannel threadCha
         List<MessageEmbed> embeds = List.of(HelpSystemHelper.embedWith(
                 "Code is much easier to read if posted with **syntax highlighting** and proper formatting.",
                 useCodeSyntaxExampleImage ? "attachment://" + CODE_SYNTAX_EXAMPLE_PATH : null),
-                HelpSystemHelper.embedWith(
-                        """
-                                If your code is **long**, or you have **multiple files** to share, consider posting it on sites \
-                                    like https://pastebin.com/ and share the link instead, that is easier to browse for helpers."""),
                 HelpSystemHelper.embedWith(
                         """
                                 If nobody is calling back, that usually means that your question was **not well asked** and \
@@ -171,12 +183,12 @@ Optional<ForumTag> getActivityTagOfChannel(ThreadChannel channel) {
         return getFirstMatchingTagOfChannel(threadActivityTagNames, channel);
     }
 
-    private static Optional<ForumTag> getFirstMatchingTagOfChannel(Set<String> tagNamesToMatch,
+    private Optional<ForumTag> getFirstMatchingTagOfChannel(Set<String> tagNamesToMatch,
             ThreadChannel channel) {
         return channel.getAppliedTags()
             .stream()
             .filter(tag -> tagNamesToMatch.contains(tag.getName()))
-            .findFirst();
+            .min(byCategoryCommonnessAsc);
     }
 
     RestAction<Void> changeChannelCategory(ThreadChannel channel, String category) {
@@ -187,8 +199,8 @@ RestAction<Void> changeChannelActivity(ThreadChannel channel, ThreadActivity act
         return changeMatchingTagOfChannel(activity.getTagName(), threadActivityTagNames, channel);
     }
 
-    private static RestAction<Void> changeMatchingTagOfChannel(String tagName,
-            Set<String> tagNamesToMatch, ThreadChannel channel) {
+    private RestAction<Void> changeMatchingTagOfChannel(String tagName, Set<String> tagNamesToMatch,
+            ThreadChannel channel) {
         List<ForumTag> tags = new ArrayList<>(channel.getAppliedTags());
 
         Optional<ForumTag> currentTag = getFirstMatchingTagOfChannel(tagNamesToMatch, channel);

application/src/main/java/org/togetherjava/tjbot/commands/help/HelpThreadCreatedListener.java

@@ -9,13 +9,15 @@
 import net.dv8tion.jda.api.events.channel.ChannelCreateEvent;
 import net.dv8tion.jda.api.hooks.ListenerAdapter;
 import net.dv8tion.jda.api.requests.RestAction;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 import org.togetherjava.tjbot.commands.EventReceiver;
 
-import javax.annotation.Nonnull;
-
 import java.time.Instant;
 import java.time.temporal.ChronoUnit;
+import java.util.concurrent.Executors;
+import java.util.concurrent.ScheduledExecutorService;
 import java.util.concurrent.TimeUnit;
 
 /**
@@ -25,6 +27,9 @@
  * user.
  */
 public final class HelpThreadCreatedListener extends ListenerAdapter implements EventReceiver {
+    private static final Logger logger = LoggerFactory.getLogger(HelpThreadCreatedListener.class);
+    private static final ScheduledExecutorService SERVICE = Executors.newScheduledThreadPool(2);
+
     private final HelpSystemHelper helper;
     private final Cache<Long, Instant> threadIdToCreatedAtCache = Caffeine.newBuilder()
         .maximumSize(1_000)
@@ -41,7 +46,7 @@ public HelpThreadCreatedListener(HelpSystemHelper helper) {
     }
 
     @Override
-    public void onChannelCreate(@Nonnull ChannelCreateEvent createEvent) {
+    public void onChannelCreate(ChannelCreateEvent createEvent) {
         if (!createEvent.getChannelType().isThread()) {
             return;
         }
@@ -69,7 +74,20 @@ private boolean wasThreadAlreadyHandled(long threadChannelId) {
     private void handleHelpThreadCreated(ThreadChannel threadChannel) {
         helper.writeHelpThreadToDatabase(threadChannel.getOwnerIdLong(), threadChannel);
 
-        createMessages(threadChannel).queue();
+        Runnable createMessages = () -> {
+            try {
+                createMessages(threadChannel).queue();
+            } catch (Exception e) {
+                logger.error(
+                        "Unknown error while creating messages after help-thread ({}) creation",
+                        threadChannel.getId(), e);
+            }
+        };
+
+        // The creation is delayed, because otherwise it could be too fast and be executed
+        // after Discord created the thread, but before Discord send OPs initial message.
+        // Sending messages at that moment is not allowed.
+        SERVICE.schedule(createMessages, 5, TimeUnit.SECONDS);
     }
 
     private RestAction<Message> createMessages(ThreadChannel threadChannel) {

application/src/main/java/org/togetherjava/tjbot/commands/help/package-info.java

@@ -1,6 +1,7 @@
 /**
- * This package offers all functionality for the help system. For example commands that let users
- * ask questions, such as {@link org.togetherjava.tjbot.commands.help.AskCommand}.
+ * This package offers all functionality for the help system. For example commands that handles the
+ * actions taken after creating a help thread
+ * {@link org.togetherjava.tjbot.commands.help.HelpThreadCreatedListener}.
  */
 @MethodsReturnNonnullByDefault
 @ParametersAreNonnullByDefault

build.gradle

@@ -2,7 +2,7 @@ plugins {
     id 'java'
     id "com.diffplug.spotless" version "6.12.0"
     id "org.sonarqube" version "3.5.0.2730"
-    id "name.remal.sonarlint" version "2.0.0"
+    id "name.remal.sonarlint" version "2.1.0"
 }
 
 group 'org.togetherjava'