Use 'retention' rather than 'expiry' to describe DB's retention period.

This will avoid a name clash when retransmission is implemented.

briar-api/src/net/sf/briar/api/db/DatabaseComponent.java

@@ -11,8 +11,8 @@ import net.sf.briar.api.TransportProperties;
 import net.sf.briar.api.db.event.DatabaseListener;
 import net.sf.briar.api.protocol.Ack;
 import net.sf.briar.api.protocol.AuthorId;
-import net.sf.briar.api.protocol.ExpiryAck;
-import net.sf.briar.api.protocol.ExpiryUpdate;
+import net.sf.briar.api.protocol.RetentionAck;
+import net.sf.briar.api.protocol.RetentionUpdate;
 import net.sf.briar.api.protocol.Group;
 import net.sf.briar.api.protocol.GroupId;
 import net.sf.briar.api.protocol.Message;
@@ -98,24 +98,24 @@ public interface DatabaseComponent {
 	Collection<byte[]> generateBatch(ContactId c, int maxLength,
 			Collection<MessageId> requested) throws DbException;
 
-	/**
-	 * Generates an expiry ack for the given contact. Returns null if no ack
-	 * is due.
-	 */
-	ExpiryAck generateExpiryAck(ContactId c) throws DbException;
-
-	/**
-	 * Generates an expiry update for the given contact. Returns null if no
-	 * update is due.
-	 */
-	ExpiryUpdate generateExpiryUpdate(ContactId c) throws DbException;
-
 	/**
 	 * Generates an offer for the given contact. Returns null if there are no
 	 * messages to offer.
 	 */
 	Offer generateOffer(ContactId c, int maxMessages) throws DbException;
 
+	/**
+	 * Generates a retention ack for the given contact. Returns null if no ack
+	 * is due.
+	 */
+	RetentionAck generateRetentionAck(ContactId c) throws DbException;
+
+	/**
+	 * Generates a retention update for the given contact. Returns null if no
+	 * update is due.
+	 */
+	RetentionUpdate generateRetentionUpdate(ContactId c) throws DbException;
+
 	/**
 	 * Generates a subscription ack for the given contact. Returns null if no
 	 * ack is due.
@@ -200,12 +200,6 @@ public interface DatabaseComponent {
 	/** Processes an ack from the given contact. */
 	void receiveAck(ContactId c, Ack a) throws DbException;
 
-	/** Processes an expiry ack from the given contact. */
-	void receiveExpiryAck(ContactId c, ExpiryAck a) throws DbException;
-
-	/** Processes an expiry update from the given contact. */
-	void receiveExpiryUpdate(ContactId c, ExpiryUpdate u) throws DbException;
-
 	/** Processes a message from the given contact. */
 	void receiveMessage(ContactId c, Message m) throws DbException;
 
@@ -219,6 +213,13 @@ public interface DatabaseComponent {
 	 */
 	Request receiveOffer(ContactId c, Offer o) throws DbException;
 
+	/** Processes a retention ack from the given contact. */
+	void receiveRetentionAck(ContactId c, RetentionAck a) throws DbException;
+
+	/** Processes a retention update from the given contact. */
+	void receiveRetentionUpdate(ContactId c, RetentionUpdate u)
+			throws DbException;
+
 	/** Processes a subscription ack from the given contact. */
 	void receiveSubscriptionAck(ContactId c, SubscriptionAck a)
 			throws DbException;

briar-api/src/net/sf/briar/api/protocol/ExpiryUpdate.java

@@ -1,23 +0,0 @@
-package net.sf.briar.api.protocol;
-
-/**
- * A packet updating the recipient's view of the expiry time of the sender's
- * database.
- */
-public class ExpiryUpdate {
-
-	private final long expiry, version;
-
-	public ExpiryUpdate(long expiry, long version) {
-		this.expiry = expiry;
-		this.version = version;
-	}
-
-	public long getExpiryTime() {
-		return expiry;
-	}
-
-	public long getVersionNumber() {
-		return version;
-	}
-}

briar-api/src/net/sf/briar/api/protocol/ProtocolReader.java

@@ -9,12 +9,6 @@ public interface ProtocolReader {
 	boolean hasAck() throws IOException;
 	Ack readAck() throws IOException;
 
-	boolean hasExpiryAck() throws IOException;
-	ExpiryAck readExpiryAck() throws IOException;
-
-	boolean hasExpiryUpdate() throws IOException;
-	ExpiryUpdate readExpiryUpdate() throws IOException;
-
 	boolean hasMessage() throws IOException;
 	UnverifiedMessage readMessage() throws IOException;
 
@@ -24,6 +18,12 @@ public interface ProtocolReader {
 	boolean hasRequest() throws IOException;
 	Request readRequest() throws IOException;
 
+	boolean hasRetentionAck() throws IOException;
+	RetentionAck readRetentionAck() throws IOException;
+
+	boolean hasRetentionUpdate() throws IOException;
+	RetentionUpdate readRetentionUpdate() throws IOException;
+
 	boolean hasSubscriptionAck() throws IOException;
 	SubscriptionAck readSubscriptionAck() throws IOException;
 

briar-api/src/net/sf/briar/api/protocol/ProtocolWriter.java

@@ -10,16 +10,16 @@ public interface ProtocolWriter {
 
 	void writeAck(Ack a) throws IOException;
 
-	void writeExpiryAck(ExpiryAck a) throws IOException;
-
-	void writeExpiryUpdate(ExpiryUpdate e) throws IOException;
-
 	void writeMessage(byte[] raw) throws IOException;
 
 	void writeOffer(Offer o) throws IOException;
 
 	void writeRequest(Request r) throws IOException;
 
+	void writeRetentionAck(RetentionAck a) throws IOException;
+
+	void writeRetentionUpdate(RetentionUpdate u) throws IOException;
+
 	void writeSubscriptionAck(SubscriptionAck a) throws IOException;
 
 	void writeSubscriptionUpdate(SubscriptionUpdate u) throws IOException;

briar-api/src/net/sf/briar/api/protocol/RetentionAck.java

@@ -1,11 +1,11 @@
 package net.sf.briar.api.protocol;
 
-/** A packet acknowledging a (@link ExpiryUpdate} */
-public class ExpiryAck {
+/** A packet acknowledging a (@link RetentionUpdate} */
+public class RetentionAck {
 
 	private final long version;
 
-	public ExpiryAck(long version) {
+	public RetentionAck(long version) {
 		this.version = version;
 	}
 

briar-api/src/net/sf/briar/api/protocol/RetentionUpdate.java

@@ -0,0 +1,23 @@
+package net.sf.briar.api.protocol;
+
+/**
+ * A packet updating the recipient's view of the retention time of the sender's
+ * database.
+ */
+public class RetentionUpdate {
+
+	private final long retention, version;
+
+	public RetentionUpdate(long retention, long version) {
+		this.retention = retention;
+		this.version = version;
+	}
+
+	public long getRetentionTime() {
+		return retention;
+	}
+
+	public long getVersionNumber() {
+		return version;
+	}
+}

briar-api/src/net/sf/briar/api/protocol/Types.java

@@ -6,11 +6,11 @@ public interface Types {
 	int AUTHOR = 0;
 	int GROUP = 1;
 	int ACK = 2;
-	int EXPIRY_ACK = 3;
-	int EXPIRY_UPDATE = 4;
-	int MESSAGE = 5;
-	int OFFER = 6;
-	int REQUEST = 7;
+	int MESSAGE = 3;
+	int OFFER = 4;
+	int REQUEST = 5;
+	int RETENTION_ACK = 6;
+	int RETENTION_UPDATE = 7;
 	int SUBSCRIPTION_ACK = 8;
 	int SUBSCRIPTION_UPDATE = 9;
 	int TRANSPORT_ACK = 10;