add Interaction Object for Messages

src/main/java/net/dv8tion/jda/api/entities/Message.java

@@ -22,6 +22,7 @@
 import net.dv8tion.jda.api.Permission;
 import net.dv8tion.jda.api.exceptions.HttpException;
 import net.dv8tion.jda.api.exceptions.InsufficientPermissionException;
+import net.dv8tion.jda.api.interactions.InteractionType;
 import net.dv8tion.jda.api.interactions.components.ActionRow;
 import net.dv8tion.jda.api.interactions.components.Button;
 import net.dv8tion.jda.api.interactions.components.ComponentLayout;
@@ -2471,6 +2472,9 @@ default MessageAction reply(@Nonnull byte[] data, @Nonnull String name, @Nonnull
     @Nonnull
     MessageType getType();
 
+    @Nullable
+    Interaction getInteraction();
+
     /**
      * Mention constants, useful for use with {@link java.util.regex.Pattern Patterns}
      */
@@ -3035,4 +3039,58 @@ public boolean isSpoiler()
         }
 
     }
+
+    class Interaction implements ISnowflake
+    {
+
+        private final long id;
+        private final int type;
+        private final String name;
+        private final User user;
+        private final Member member;
+
+        public Interaction(long id, int type, String name, User user, Member member)
+        {
+            this.id = id;
+            this.type = type;
+            this.name = name;
+            this.user = user;
+            this.member = member;
+        }
+
+        @Override
+        public long getIdLong()
+        {
+            return id;
+        }
+
+        public int getTypeRaw()
+        {
+            return type;
+        }
+
+        @Nonnull
+        public InteractionType getType()
+        {
+            return InteractionType.fromKey(getTypeRaw());
+        }
+
+        @Nonnull
+        public String getName()
+        {
+            return name;
+        }
+
+        @Nonnull
+        public User getUser()
+        {
+            return user;
+        }
+
+        @Nullable
+        public Member getMember()
+        {
+            return member;
+        }
+    }
 }

src/main/java/net/dv8tion/jda/internal/entities/AbstractMessage.java

@@ -28,6 +28,7 @@
 import org.apache.commons.collections4.Bag;
 
 import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
 import java.io.IOException;
 import java.io.UncheckedIOException;
 import java.time.OffsetDateTime;
@@ -601,4 +602,12 @@ public MessageType getType()
         unsupported();
         return null;
     }
+
+    @Nullable
+    @Override
+    public Message.Interaction getInteraction()
+    {
+        unsupported();
+        return null;
+    }
 }

src/main/java/net/dv8tion/jda/internal/entities/EntityBuilder.java

@@ -1270,13 +1270,24 @@ else if (MISSING_CHANNEL.equals(ex.getMessage()))
                     .collect(Collectors.toList());
         }
 
+        Message.Interaction messageInteraction = null;
+        if (!jsonObject.isNull("interaction"))
+        {
+            GuildImpl guild = null;
+            if (channel instanceof GuildChannel)
+            {
+                guild = (GuildImpl) ((GuildChannel) (channel)).getGuild();
+            }
+            messageInteraction = createMessageInteraction(guild, jsonObject.getObject("interaction"));
+        }
+
         if (type == MessageType.UNKNOWN)
             throw new IllegalArgumentException(UNKNOWN_MESSAGE_TYPE);
         if (!type.isSystem())
         {
             message = new ReceivedMessage(id, channel, type, referencedMessage, fromWebhook,
                     mentionsEveryone, mentionedUsers, mentionedRoles, tts, pinned,
-                    content, nonce, user, member, activity, editTime, reactions, attachments, embeds, stickers, components, flags);
+                    content, nonce, user, member, activity, editTime, reactions, attachments, embeds, stickers, components, flags, messageInteraction);
         }
         else
         {
@@ -1521,6 +1532,29 @@ public MessageSticker createSticker(DataObject content)
         return new MessageSticker(id, name, description, packId, asset, format, tags);
     }
 
+    public Message.Interaction createMessageInteraction(GuildImpl guildImpl, DataObject content)
+    {
+        final long id = content.getLong("id");
+        final int type = content.getInt("type");
+        final String name = content.getString("name");
+        DataObject userJson = content.getObject("user");
+        User user = null;
+        MemberImpl member = null;
+        if (!content.isNull("member") && guildImpl != null)
+        {
+            DataObject memberJson = content.getObject("member");
+            memberJson.put("user", userJson);
+            member = createMember(guildImpl, memberJson);
+            user = member.getUser();
+        }
+        else
+        {
+            user = createUser(userJson);
+        }
+
+        return new Message.Interaction(id, type, name, user, member);
+    }
+
     @Nullable
     public PermissionOverride createPermissionOverride(DataObject override, AbstractChannelImpl<?, ?> chan)
     {

src/main/java/net/dv8tion/jda/internal/entities/ReceivedMessage.java

@@ -75,6 +75,7 @@ public class ReceivedMessage extends AbstractMessage
     protected final TLongSet mentionedUsers;
     protected final TLongSet mentionedRoles;
     protected final int flags;
+    protected final Message.Interaction interaction;
 
     protected InteractionHook interactionHook = null; // late-init
 
@@ -93,7 +94,7 @@ public ReceivedMessage(
         long id, MessageChannel channel, MessageType type, Message referencedMessage,
         boolean fromWebhook, boolean mentionsEveryone, TLongSet mentionedUsers, TLongSet mentionedRoles, boolean tts, boolean pinned,
         String content, String nonce, User author, Member member, MessageActivity activity, OffsetDateTime editTime,
-        List<MessageReaction> reactions, List<Attachment> attachments, List<MessageEmbed> embeds, List<MessageSticker> stickers, List<ActionRow> components, int flags)
+        List<MessageReaction> reactions, List<Attachment> attachments, List<MessageEmbed> embeds, List<MessageSticker> stickers, List<ActionRow> components, int flags, Message.Interaction interaction)
     {
         super(content, nonce, tts);
         this.id = id;
@@ -116,6 +117,7 @@ public ReceivedMessage(
         this.mentionedUsers = mentionedUsers;
         this.mentionedRoles = mentionedRoles;
         this.flags = flags;
+        this.interaction = interaction;
     }
 
     public ReceivedMessage withHook(InteractionHook hook)
@@ -300,6 +302,13 @@ public MessageType getType()
         return type;
     }
 
+    @Nullable
+    @Override
+    public Interaction getInteraction()
+    {
+        return interaction;
+    }
+
     @Override
     public long getIdLong()
     {

src/main/java/net/dv8tion/jda/internal/entities/SystemMessage.java

@@ -38,7 +38,7 @@ public SystemMessage(
         List<MessageReaction> reactions, List<Attachment> attachments, List<MessageEmbed> embeds, List<MessageSticker> stickers, int flags)
     {
         super(id, channel, type, null, fromWebhook, mentionsEveryone, mentionedUsers, mentionedRoles,
-            tts, pinned, content, nonce, author, member, activity, editTime, reactions, attachments, embeds, stickers, Collections.emptyList(), flags);
+            tts, pinned, content, nonce, author, member, activity, editTime, reactions, attachments, embeds, stickers, Collections.emptyList(), flags, null);
     }
 
     @Nonnull