Add comments for group visibility.

bramble-api/src/main/java/org/briarproject/bramble/api/sync/event/MessageSharedEvent.java

@@ -3,6 +3,7 @@ package org.briarproject.bramble.api.sync.event;
 import org.briarproject.bramble.api.contact.ContactId;
 import org.briarproject.bramble.api.event.Event;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.bramble.api.sync.Group.Visibility;
 import org.briarproject.bramble.api.sync.GroupId;
 import org.briarproject.bramble.api.sync.MessageId;
 
@@ -36,6 +37,13 @@ public class MessageSharedEvent extends Event {
 		return groupId;
 	}
 
+	/**
+	 * Returns the IDs of all contacts for which the visibility of the
+	 * message's group is either {@link Visibility#SHARED shared} or
+	 * {@link Visibility#VISIBLE visible}. The value in the map is true if the
+	 * group is {@link Visibility#SHARED shared} or false if the group is
+	 * {@link Visibility#VISIBLE visible}.
+	 */
 	public Map<ContactId, Boolean> getGroupVisibility() {
 		return groupVisibility;
 	}

bramble-core/src/main/java/org/briarproject/bramble/db/Database.java

@@ -352,8 +352,11 @@ interface Database<T> {
 			throws DbException;
 
 	/**
-	 * Returns the IDs of all contacts to which the given group's visibility is
+	 * Returns the IDs of all contacts for which the given group's visibility
-	 * either {@link Visibility VISIBLE} or {@link Visibility SHARED}.
+	 * is either {@link Visibility#SHARED shared} or
+	 * {@link Visibility#VISIBLE visible}. The value in the map is true if the
+	 * group is {@link Visibility#SHARED shared} or false if the group is
+	 * {@link Visibility#VISIBLE visible}.
 	 * <p/>
 	 * Read-only.
 	 */

bramble-core/src/main/java/org/briarproject/bramble/mailbox/MailboxUploadWorker.java

@@ -385,6 +385,9 @@ class MailboxUploadWorker implements MailboxWorker, ConnectivityObserver,
 			}
 		} else if (e instanceof MessageSharedEvent) {
 			MessageSharedEvent m = (MessageSharedEvent) e;
+			// If the contact is present in the map (ie the value is not null)
+			// and the value is true, the message's group is shared with the
+			// contact and therefore the message may now be sendable
 			if (m.getGroupVisibility().get(contactId) == TRUE) {
 				LOG.info("Message shared");
 				onDataToSend();

bramble-core/src/main/java/org/briarproject/bramble/sync/DuplexOutgoingSession.java

@@ -235,6 +235,9 @@ class DuplexOutgoingSession implements SyncSession, EventListener {
 			if (c.getContactId().equals(contactId)) interrupt();
 		} else if (e instanceof MessageSharedEvent) {
 			MessageSharedEvent m = (MessageSharedEvent) e;
+			// If the contact is present in the map (ie the value is not null)
+			// and the value is true, the message's group is shared with the
+			// contact and therefore the message may now be sendable
 			if (m.getGroupVisibility().get(contactId) == TRUE) {
 				generateOffer();
 			}