Implement access and retrieval of message_reference

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

@@ -226,6 +226,44 @@ public interface Message extends ISnowflake, Formattable
     @Nullable
     Message getReferencedMessage();
 
+    /**
+     * This returns the id of the referenced message, never null
+     *
+     * @throws java.lang.IllegalStateException
+     *         If this message does not have a reference
+     *
+     * @return The referenced message id
+     */
+    long getReferencedMessageIdLong();
+
+    /**
+     * Retrieves the referenced message for this message. If one is already present, it will be returned.
+     *
+     * @throws java.lang.IllegalStateException
+     *         If this message does not have a reference
+     *
+     * @return {@link net.dv8tion.jda.api.requests.RestAction RestAction} - Type: {@link net.dv8tion.jda.api.entities.Message}
+     */
+    RestAction<Message> retrieveReferencedMessage();
+
+    /**
+     * This returns the id of the referenced message, never null
+     *
+     * @throws java.lang.IllegalStateException
+     *         If this message does not have a reference
+     *
+     * @return The referenced message id
+     */
+    @Nonnull
+    String getReferencedMessageId();
+
+    /**
+     * This determines whether a message has a reference, for use with {@link Message#retrieveReferencedMessage()}
+     *
+     * @return Whether this message has a reference attached to it
+     */
+    boolean hasReferencedMessage();
+
     /**
      * An immutable list of all mentioned {@link net.dv8tion.jda.api.entities.User Users}.
      * <br>If no user was mentioned, this list is empty. Elements are sorted in order of appearance. This only

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

@@ -32,6 +32,8 @@
 import java.time.OffsetDateTime;
 import java.util.*;
 
+import org.jetbrains.annotations.NotNull;
+
 public abstract class AbstractMessage implements Message
 {
     protected static final String UNSUPPORTED = "This operation is not supported for Messages of this type!";
@@ -110,6 +112,34 @@ public Message getReferencedMessage()
         return null;
     }
 
+    @NotNull
+    @Override
+    public String getReferencedMessageId()
+    {
+        unsupported();
+        return null;
+    }
+
+    @Override
+    public long getReferencedMessageIdLong()
+    {
+        unsupported();
+        return 0;
+    }
+
+    @Override
+    public RestAction<Message> retrieveReferencedMessage()
+    {
+        unsupported();
+        return null;
+    }
+
+    @Override
+    public boolean hasReferencedMessage()
+    {
+        return false;
+    }
+
     @Nonnull
     @Override
     public Bag<User> getMentionedUsersBag()

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

@@ -1232,15 +1232,29 @@ else if (MISSING_CHANNEL.equals(ex.getMessage()))
 
         if (type == MessageType.UNKNOWN)
             throw new IllegalArgumentException(UNKNOWN_MESSAGE_TYPE);
+
+        MessageReference messageReference = null;
+
+        if (!jsonObject.isNull("message_reference"))
+        {
+            DataObject messageReferenceJson = jsonObject.getObject("message_reference");
+
+            messageReference = new MessageReference(
+                    messageReferenceJson.getLong("message_id"),
+                    messageReferenceJson.getLong("channel_id"),
+                    referencedMessage
+            );
+        }
+
         if (!type.isSystem())
         {
-            message = new ReceivedMessage(id, channel, type, referencedMessage, fromWebhook,
+            message = new ReceivedMessage(id, channel, type, messageReference, fromWebhook,
                     mentionsEveryone, mentionedUsers, mentionedRoles, tts, pinned,
                     content, nonce, user, member, activity, editTime, reactions, attachments, embeds, stickers, components, flags);
         }
         else
         {
-            message = new SystemMessage(id, channel, type, fromWebhook,
+            message = new SystemMessage(id, channel, type, messageReference, fromWebhook,
                     mentionsEveryone, mentionedUsers, mentionedRoles, tts, pinned,
                     content, nonce, user, member, activity, editTime, reactions, attachments, embeds, stickers, flags);
             return message; // We don't need to parse mentions for system messages, they are always empty anyway

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

@@ -0,0 +1,43 @@
+package net.dv8tion.jda.internal.entities;
+
+import net.dv8tion.jda.api.entities.Message;
+
+public class MessageReference
+{
+    private final long messageId;
+    private final long channelId;
+    private final Message referencedMessage;
+
+    public MessageReference(long messageId, long channelId, Message referencedMessage)
+    {
+        this.messageId = messageId;
+        this.channelId = channelId;
+        this.referencedMessage = referencedMessage;
+    }
+
+    public Message getReferencedMessage()
+    {
+        return referencedMessage;
+    }
+
+    public long getMessageIdLong()
+    {
+        return messageId;
+    }
+
+    public long getChannelIdLong()
+    {
+        return channelId;
+    }
+
+
+    public String getMessageId()
+    {
+        return Long.toUnsignedString(getMessageIdLong());
+    }
+
+    public String getChannelId()
+    {
+        return Long.toUnsignedString(getChannelIdLong());
+    }
+}

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

@@ -33,6 +33,7 @@
 import net.dv8tion.jda.api.utils.data.DataObject;
 import net.dv8tion.jda.internal.JDAImpl;
 import net.dv8tion.jda.internal.requests.CompletedRestAction;
+import net.dv8tion.jda.internal.requests.RestActionImpl;
 import net.dv8tion.jda.internal.requests.Route;
 import net.dv8tion.jda.internal.requests.restaction.AuditableRestActionImpl;
 import net.dv8tion.jda.internal.requests.restaction.MessageActionImpl;
@@ -57,6 +58,7 @@ public class ReceivedMessage extends AbstractMessage
     protected final long id;
     protected final MessageType type;
     protected final MessageChannel channel;
+    protected final MessageReference messageReference;
     protected final Message referencedMessage;
     protected final boolean fromWebhook;
     protected final boolean mentionsEveryone;
@@ -88,15 +90,17 @@ public class ReceivedMessage extends AbstractMessage
     protected List<String> invites = null;
 
     public ReceivedMessage(
-        long id, MessageChannel channel, MessageType type, Message referencedMessage,
+        long id, MessageChannel channel, MessageType type, MessageReference messageReference,
         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)
     {
         super(content, nonce, tts);
         this.id = id;
         this.channel = channel;
-        this.referencedMessage = referencedMessage;
+        this.messageReference = messageReference;
+        this.referencedMessage = (messageReference != null) ? messageReference.getReferencedMessage() : null;
+
         this.type = type;
         this.api = (channel != null) ? (JDAImpl) channel.getJDA() : null;
         this.fromWebhook = fromWebhook;
@@ -135,6 +139,52 @@ public Message getReferencedMessage()
         return referencedMessage;
     }
 
+    @Override
+    public long getReferencedMessageIdLong()
+    {
+        if (messageReference == null)
+        {
+            throw new IllegalStateException("Cannot get an id for a non-existent reference.");
+        }
+        return messageReference.getMessageIdLong();
+    }
+
+
+    @Nonnull
+    @Override
+    public String getReferencedMessageId()
+    {
+        if (messageReference == null)
+        {
+            throw new IllegalStateException("Cannot get an id for a non-existent reference.");
+        }
+
+        return Long.toUnsignedString(getReferencedMessageIdLong());
+    }
+
+    @Override
+    public boolean hasReferencedMessage()
+    {
+        return messageReference != null;
+    }
+
+    @Override
+    public RestAction<Message> retrieveReferencedMessage()
+    {
+        if (messageReference == null) {
+            throw new IllegalStateException("Cannot get a retrieve a message for a non-existent reference.");
+        }
+
+        if (referencedMessage != null) {
+            return new CompletedRestAction<>(getJDA(), referencedMessage);
+        }
+
+        Route.CompiledRoute route = Route.Messages.GET_MESSAGE.compile(messageReference.getChannelId(), getReferencedMessageId());
+        JDAImpl jda = (JDAImpl) getJDA();
+        return new RestActionImpl<>(jda, route,
+                (response, request) -> jda.getEntityBuilder().createMessage(response.getObject(), getChannel(), false));
+    }
+
     @Override
     public boolean isPinned()
     {

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

@@ -29,16 +29,17 @@
 public class SystemMessage extends ReceivedMessage
 {
     public SystemMessage(
-        long id, MessageChannel channel, MessageType type,
+        long id, MessageChannel channel, MessageType type, MessageReference messageReference,
         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, int flags)
     {
-        super(id, channel, type, null, fromWebhook, mentionsEveryone, mentionedUsers, mentionedRoles,
+        super(id, channel, type, messageReference, fromWebhook, mentionsEveryone, mentionedUsers, mentionedRoles,
             tts, pinned, content, nonce, author, member, activity, editTime, reactions, attachments, embeds, stickers, Collections.emptyList(), flags);
     }
 
+
     @Nonnull
     @Override
     public RestAction<Void> pin()