Move responsibility for closing connections from limiter to plugin.

bramble-core/src/main/java/org/briarproject/bramble/plugin/bluetooth/BluetoothConnectionLimiter.java

@@ -45,10 +45,9 @@ interface BluetoothConnectionLimiter {
 	boolean canOpenContactConnection();
 
 	/**
-	 * Informs the limiter that a contact connection has been opened. The
+	 * Informs the limiter that a contact connection has been opened.
-	 * limiter may close the new connection if key agreement is in progress.
 	 * <p/>
-	 * Returns false if the limiter has closed the new connection.
+	 * Returns true if the connection is allowed.
 	 */
 	boolean contactConnectionOpened(DuplexTransportConnection conn,
 			boolean incoming);

bramble-core/src/main/java/org/briarproject/bramble/plugin/bluetooth/BluetoothConnectionLimiterImpl.java

@@ -6,7 +6,6 @@ import org.briarproject.bramble.api.plugin.duplex.DuplexTransportConnection;
 import org.briarproject.bramble.api.sync.event.CloseSyncConnectionsEvent;
 import org.briarproject.bramble.api.system.Clock;
 
-import java.io.IOException;
 import java.util.Iterator;
 import java.util.LinkedList;
 import java.util.List;
@@ -18,10 +17,8 @@ import javax.inject.Inject;
 
 import static java.lang.Math.min;
 import static java.util.logging.Level.INFO;
-import static java.util.logging.Level.WARNING;
 import static java.util.logging.Logger.getLogger;
 import static org.briarproject.bramble.api.plugin.BluetoothConstants.ID;
-import static org.briarproject.bramble.util.LogUtils.logException;
 
 @NotNullByDefault
 @ThreadSafe
@@ -83,25 +80,24 @@ class BluetoothConnectionLimiterImpl implements BluetoothConnectionLimiter {
 	@Override
 	public boolean contactConnectionOpened(DuplexTransportConnection conn,
 			boolean incoming) {
-		boolean accept;
 		synchronized (lock) {
 			if (keyAgreementInProgress) {
 				LOG.info("Refusing contact connection during key agreement");
-				accept = false;
+				return false;
 			} else {
 				long now = clock.currentTimeMillis();
-				accept = incoming || isContactConnectionAllowedByLimit(now);
+				if (incoming || isContactConnectionAllowedByLimit(now)) {
-				if (accept) {
 					connections.add(new ConnectionRecord(conn, now));
 					if (connections.size() > connectionLimit) {
 						LOG.info("Attempting to raise connection limit");
 						timeOfLastAttempt = now;
 					}
+					return true;
+				} else {
+					return false;
 				}
 			}
 		}
-		if (!accept) tryToClose(conn);
-		return accept;
 	}
 
 	@Override
@@ -113,15 +109,6 @@ class BluetoothConnectionLimiterImpl implements BluetoothConnectionLimiter {
 		}
 	}
 
-	private void tryToClose(DuplexTransportConnection conn) {
-		try {
-			conn.getWriter().dispose(false);
-			conn.getReader().dispose(false, false);
-		} catch (IOException e) {
-			logException(LOG, WARNING, e);
-		}
-	}
-
 	@Override
 	public void connectionClosed(DuplexTransportConnection conn,
 			boolean exception) {

bramble-core/src/main/java/org/briarproject/bramble/plugin/bluetooth/BluetoothPlugin.java

@@ -235,11 +235,22 @@ abstract class BluetoothPlugin<SS> implements DuplexPlugin, EventListener {
 			if (connectionLimiter.contactConnectionOpened(conn, true)) {
 				backoff.reset();
 				callback.handleConnection(conn);
+			} else {
+				tryToClose(conn);
 			}
 			if (!running) return;
 		}
 	}
 
+	private void tryToClose(DuplexTransportConnection conn) {
+		try {
+			conn.getWriter().dispose(false);
+			conn.getReader().dispose(false, false);
+		} catch (IOException e) {
+			logException(LOG, WARNING, e);
+		}
+	}
+
 	@Override
 	public void stop() {
 		running = false;
@@ -328,8 +339,12 @@ abstract class BluetoothPlugin<SS> implements DuplexPlugin, EventListener {
 		if (isNullOrEmpty(uuid)) return null;
 		DuplexTransportConnection conn = connect(address, uuid);
 		if (conn == null) return null;
-		if (connectionLimiter.contactConnectionOpened(conn, false)) return conn;
+		if (connectionLimiter.contactConnectionOpened(conn, false)) {
-		return null;
+			return conn;
+		} else {
+			tryToClose(conn);
+			return null;
+		}
 	}
 
 	@Override