Further progress towards incremental subscription updates.

api/net/sf/briar/api/protocol/PacketFactory.java

@@ -14,8 +14,8 @@ public interface PacketFactory {
 
 	Request createRequest(BitSet requested, int length);
 
-	SubscriptionUpdate createSubscriptionUpdate(Map<Group, Long> subs,
-			long timestamp);
+	SubscriptionUpdate createSubscriptionUpdate(Map<GroupId, GroupId> holes,
+			Map<Group, Long> subs, long expiry, long timestamp);
 
 	TransportUpdate createTransportUpdate(Collection<Transport> transports,
 			long timestamp);

api/net/sf/briar/api/protocol/ProtocolConstants.java

@@ -21,9 +21,6 @@ public interface ProtocolConstants {
 	/** The maximum length of a property's key or value in UTF-8 bytes. */
 	static final int MAX_PROPERTY_LENGTH = 100;
 
-	/** The maximum number of groups a node may subscribe to. */
-	static final int MAX_GROUPS = 5000;
-
 	/** The maximum length of a group's name in UTF-8 bytes. */
 	static final int MAX_GROUP_NAME_LENGTH = 50;
 

api/net/sf/briar/api/protocol/SubscriptionUpdate.java

@@ -5,9 +5,18 @@ import java.util.Map;
 /** A packet updating the sender's subscriptions. */
 public interface SubscriptionUpdate {
 
+	/** Returns the holes contained in the update. */
+	Map<GroupId, GroupId> getHoles();
+
 	/** Returns the subscriptions contained in the update. */
 	Map<Group, Long> getSubscriptions();
 
+	/**
+	 * Returns the expiry time of the contact's database. Messages that are
+	 * older than the expiry time must not be sent to the contact.
+	 */
+	long getExpiryTime();
+
 	/**
 	 * Returns the update's timestamp. Updates that are older than the newest
 	 * update received from the same contact must be ignored.