Move some duplicated code into utility methods.

bramble-core/src/main/java/org/briarproject/bramble/plugin/Connection.java

@@ -1,10 +1,13 @@
 package org.briarproject.bramble.plugin;
 
+import org.briarproject.bramble.api.db.DbException;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.plugin.ConnectionRegistry;
 import org.briarproject.bramble.api.plugin.TransportConnectionReader;
 import org.briarproject.bramble.api.plugin.TransportConnectionWriter;
+import org.briarproject.bramble.api.plugin.TransportId;
 import org.briarproject.bramble.api.transport.KeyManager;
+import org.briarproject.bramble.api.transport.StreamContext;
 import org.briarproject.bramble.api.transport.StreamReaderFactory;
 import org.briarproject.bramble.api.transport.StreamWriterFactory;
 
@@ -12,6 +15,8 @@ import java.io.IOException;
 import java.io.InputStream;
 import java.util.logging.Logger;
 
+import javax.annotation.Nullable;
+
 import static java.util.logging.Level.WARNING;
 import static java.util.logging.Logger.getLogger;
 import static org.briarproject.bramble.api.transport.TransportConstants.TAG_LENGTH;
@@ -37,7 +42,20 @@ abstract class Connection {
 		this.streamWriterFactory = streamWriterFactory;
 	}
 
-	byte[] readTag(InputStream in) throws IOException {
+	@Nullable
+	StreamContext recogniseTag(TransportConnectionReader reader,
+			TransportId transportId) {
+		StreamContext ctx;
+		try {
+			byte[] tag = readTag(reader.getInputStream());
+			return keyManager.getStreamContext(transportId, tag);
+		} catch (IOException | DbException e) {
+			logException(LOG, WARNING, e);
+			return null;
+		}
+	}
+
+	private byte[] readTag(InputStream in) throws IOException {
 		byte[] tag = new byte[TAG_LENGTH];
 		read(in, tag);
 		return tag;

bramble-core/src/main/java/org/briarproject/bramble/plugin/HandshakeConnection.java

@@ -3,6 +3,7 @@ package org.briarproject.bramble.plugin;
 import org.briarproject.bramble.api.contact.ContactExchangeManager;
 import org.briarproject.bramble.api.contact.HandshakeManager;
 import org.briarproject.bramble.api.contact.PendingContactId;
+import org.briarproject.bramble.api.db.DbException;
 import org.briarproject.bramble.api.plugin.ConnectionManager;
 import org.briarproject.bramble.api.plugin.ConnectionRegistry;
 import org.briarproject.bramble.api.plugin.TransportConnectionReader;
@@ -10,9 +11,15 @@ import org.briarproject.bramble.api.plugin.TransportConnectionWriter;
 import org.briarproject.bramble.api.plugin.TransportId;
 import org.briarproject.bramble.api.plugin.duplex.DuplexTransportConnection;
 import org.briarproject.bramble.api.transport.KeyManager;
+import org.briarproject.bramble.api.transport.StreamContext;
 import org.briarproject.bramble.api.transport.StreamReaderFactory;
 import org.briarproject.bramble.api.transport.StreamWriterFactory;
 
+import javax.annotation.Nullable;
+
+import static java.util.logging.Level.WARNING;
+import static org.briarproject.bramble.util.LogUtils.logException;
+
 abstract class HandshakeConnection extends Connection {
 
 	final HandshakeManager handshakeManager;
@@ -45,6 +52,17 @@ abstract class HandshakeConnection extends Connection {
 		writer = connection.getWriter();
 	}
 
+	@Nullable
+	StreamContext allocateStreamContext(PendingContactId pendingContactId,
+			TransportId transportId) {
+		try {
+			return keyManager.getStreamContext(pendingContactId, transportId);
+		} catch (DbException e) {
+			logException(LOG, WARNING, e);
+			return null;
+		}
+	}
+
 	void onError(boolean recognised) {
 		disposeOnError(reader, recognised);
 		disposeOnError(writer);

bramble-core/src/main/java/org/briarproject/bramble/plugin/IncomingDuplexSyncConnection.java

@@ -38,15 +38,7 @@ class IncomingDuplexSyncConnection extends DuplexSyncConnection
 	@Override
 	public void run() {
 		// Read and recognise the tag
-		StreamContext ctx;
+		StreamContext ctx = recogniseTag(reader, transportId);
-		try {
-			byte[] tag = readTag(reader.getInputStream());
-			ctx = keyManager.getStreamContext(transportId, tag);
-		} catch (IOException | DbException e) {
-			logException(LOG, WARNING, e);
-			onReadError(false);
-			return;
-		}
 		if (ctx == null) {
 			LOG.info("Unrecognised tag");
 			onReadError(false);
@@ -88,14 +80,7 @@ class IncomingDuplexSyncConnection extends DuplexSyncConnection
 
 	private void runOutgoingSession(ContactId contactId) {
 		// Allocate a stream context
-		StreamContext ctx;
+		StreamContext ctx = allocateStreamContext(contactId, transportId);
-		try {
-			ctx = keyManager.getStreamContext(contactId, transportId);
-		} catch (DbException e) {
-			logException(LOG, WARNING, e);
-			onWriteError();
-			return;
-		}
 		if (ctx == null) {
 			LOG.warning("Could not allocate stream context");
 			onWriteError();

bramble-core/src/main/java/org/briarproject/bramble/plugin/IncomingHandshakeConnection.java

@@ -41,15 +41,7 @@ class IncomingHandshakeConnection extends HandshakeConnection
 	@Override
 	public void run() {
 		// Read and recognise the tag
-		StreamContext ctxIn;
+		StreamContext ctxIn = recogniseTag(reader, transportId);
-		try {
-			byte[] tag = readTag(reader.getInputStream());
-			ctxIn = keyManager.getStreamContext(transportId, tag);
-		} catch (IOException | DbException e) {
-			logException(LOG, WARNING, e);
-			onError(false);
-			return;
-		}
 		if (ctxIn == null) {
 			LOG.info("Unrecognised tag");
 			onError(false);
@@ -62,14 +54,8 @@ class IncomingHandshakeConnection extends HandshakeConnection
 			return;
 		}
 		// Allocate the outgoing stream context
-		StreamContext ctxOut;
+		StreamContext ctxOut =
-		try {
+				allocateStreamContext(pendingContactId, transportId);
-			ctxOut = keyManager.getStreamContext(pendingContactId, transportId);
-		} catch (DbException e) {
-			logException(LOG, WARNING, e);
-			onError(true);
-			return;
-		}
 		if (ctxOut == null) {
 			LOG.warning("Could not allocate stream context");
 			onError(true);

bramble-core/src/main/java/org/briarproject/bramble/plugin/IncomingSimplexSyncConnection.java

@@ -1,7 +1,6 @@
 package org.briarproject.bramble.plugin;
 
 import org.briarproject.bramble.api.contact.ContactId;
-import org.briarproject.bramble.api.db.DbException;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.plugin.ConnectionRegistry;
 import org.briarproject.bramble.api.plugin.TransportConnectionReader;
@@ -41,15 +40,7 @@ class IncomingSimplexSyncConnection extends SyncConnection implements Runnable {
 	@Override
 	public void run() {
 		// Read and recognise the tag
-		StreamContext ctx;
+		StreamContext ctx = recogniseTag(reader, transportId);
-		try {
-			byte[] tag = readTag(reader.getInputStream());
-			ctx = keyManager.getStreamContext(transportId, tag);
-		} catch (IOException | DbException e) {
-			logException(LOG, WARNING, e);
-			onError(false);
-			return;
-		}
 		if (ctx == null) {
 			LOG.info("Unrecognised tag");
 			onError(false);

bramble-core/src/main/java/org/briarproject/bramble/plugin/OutgoingDuplexSyncConnection.java

@@ -41,14 +41,7 @@ class OutgoingDuplexSyncConnection extends DuplexSyncConnection
 	@Override
 	public void run() {
 		// Allocate a stream context
-		StreamContext ctx;
+		StreamContext ctx = allocateStreamContext(contactId, transportId);
-		try {
-			ctx = keyManager.getStreamContext(contactId, transportId);
-		} catch (DbException e) {
-			logException(LOG, WARNING, e);
-			onWriteError();
-			return;
-		}
 		if (ctx == null) {
 			LOG.warning("Could not allocate stream context");
 			onWriteError();
@@ -76,15 +69,7 @@ class OutgoingDuplexSyncConnection extends DuplexSyncConnection
 
 	private void runIncomingSession() {
 		// Read and recognise the tag
-		StreamContext ctx;
+		StreamContext ctx = recogniseTag(reader, transportId);
-		try {
-			byte[] tag = readTag(reader.getInputStream());
-			ctx = keyManager.getStreamContext(transportId, tag);
-		} catch (IOException | DbException e) {
-			logException(LOG, WARNING, e);
-			onReadError();
-			return;
-		}
 		// Unrecognised tags are suspicious in this case
 		if (ctx == null) {
 			LOG.warning("Unrecognised tag for returning stream");
@@ -109,8 +94,7 @@ class OutgoingDuplexSyncConnection extends DuplexSyncConnection
 			onReadError();
 			return;
 		}
-		connectionRegistry.registerConnection(contactId, transportId,
+		connectionRegistry.registerConnection(contactId, transportId, false);
-				false);
 		try {
 			// Store any transport properties discovered from the connection
 			transportPropertyManager.addRemotePropertiesFromConnection(

bramble-core/src/main/java/org/briarproject/bramble/plugin/OutgoingHandshakeConnection.java

@@ -44,14 +44,8 @@ class OutgoingHandshakeConnection extends HandshakeConnection
 	@Override
 	public void run() {
 		// Allocate the outgoing stream context
-		StreamContext ctxOut;
+		StreamContext ctxOut =
-		try {
+				allocateStreamContext(pendingContactId, transportId);
-			ctxOut = keyManager.getStreamContext(pendingContactId, transportId);
-		} catch (DbException e) {
-			logException(LOG, WARNING, e);
-			onError();
-			return;
-		}
 		if (ctxOut == null) {
 			LOG.warning("Could not allocate stream context");
 			onError();
@@ -69,15 +63,7 @@ class OutgoingHandshakeConnection extends HandshakeConnection
 			return;
 		}
 		// Read and recognise the tag
-		StreamContext ctxIn;
+		StreamContext ctxIn = recogniseTag(reader, transportId);
-		try {
-			byte[] tag = readTag(reader.getInputStream());
-			ctxIn = keyManager.getStreamContext(transportId, tag);
-		} catch (IOException | DbException e) {
-			logException(LOG, WARNING, e);
-			onError();
-			return;
-		}
 		// Unrecognised tags are suspicious in this case
 		if (ctxIn == null) {
 			LOG.warning("Unrecognised tag for returning stream");

bramble-core/src/main/java/org/briarproject/bramble/plugin/OutgoingSimplexSyncConnection.java

@@ -1,7 +1,6 @@
 package org.briarproject.bramble.plugin;
 
 import org.briarproject.bramble.api.contact.ContactId;
-import org.briarproject.bramble.api.db.DbException;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.plugin.ConnectionRegistry;
 import org.briarproject.bramble.api.plugin.TransportConnectionWriter;
@@ -47,14 +46,7 @@ class OutgoingSimplexSyncConnection extends SyncConnection implements Runnable {
 	@Override
 	public void run() {
 		// Allocate a stream context
-		StreamContext ctx;
+		StreamContext ctx = allocateStreamContext(contactId, transportId);
-		try {
-			ctx = keyManager.getStreamContext(contactId, transportId);
-		} catch (DbException e) {
-			logException(LOG, WARNING, e);
-			onError();
-			return;
-		}
 		if (ctx == null) {
 			LOG.warning("Could not allocate stream context");
 			onError();

bramble-core/src/main/java/org/briarproject/bramble/plugin/SyncConnection.java

@@ -1,9 +1,11 @@
 package org.briarproject.bramble.plugin;
 
 import org.briarproject.bramble.api.contact.ContactId;
+import org.briarproject.bramble.api.db.DbException;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.plugin.ConnectionRegistry;
 import org.briarproject.bramble.api.plugin.TransportConnectionReader;
+import org.briarproject.bramble.api.plugin.TransportId;
 import org.briarproject.bramble.api.properties.TransportPropertyManager;
 import org.briarproject.bramble.api.sync.SyncSession;
 import org.briarproject.bramble.api.sync.SyncSessionFactory;
@@ -15,7 +17,11 @@ import org.briarproject.bramble.api.transport.StreamWriterFactory;
 import java.io.IOException;
 import java.io.InputStream;
 
+import javax.annotation.Nullable;
+
+import static java.util.logging.Level.WARNING;
 import static org.briarproject.bramble.api.nullsafety.NullSafety.requireNonNull;
+import static org.briarproject.bramble.util.LogUtils.logException;
 
 @NotNullByDefault
 class SyncConnection extends Connection {
@@ -34,6 +40,17 @@ class SyncConnection extends Connection {
 		this.transportPropertyManager = transportPropertyManager;
 	}
 
+	@Nullable
+	StreamContext allocateStreamContext(ContactId contactId,
+			TransportId transportId) {
+		try {
+			return keyManager.getStreamContext(contactId, transportId);
+		} catch (DbException e) {
+			logException(LOG, WARNING, e);
+			return null;
+		}
+	}
+
 	SyncSession createIncomingSession(StreamContext ctx,
 			TransportConnectionReader r) throws IOException {
 		InputStream streamReader = streamReaderFactory.createStreamReader(