No need to use @Before to create stateful test objects.

bramble-core/src/test/java/org/briarproject/bramble/contact/ContactManagerImplTest.java

@@ -17,7 +17,6 @@ import org.briarproject.bramble.api.identity.LocalAuthor;
 import org.briarproject.bramble.api.transport.KeyManager;
 import org.briarproject.bramble.test.BrambleMockTestCase;
 import org.briarproject.bramble.test.DbExpectations;
-import org.junit.Before;
 import org.junit.Test;
 
 import java.util.Collection;
@@ -63,13 +62,9 @@ public class ContactManagerImplTest extends BrambleMockTestCase {
 	private final long timestamp = System.currentTimeMillis();
 	private final boolean alice = new Random().nextBoolean();
 
-	private ContactManagerImpl contactManager;
+	private final ContactManagerImpl contactManager =
-
+			new ContactManagerImpl(db, keyManager, identityManager,
-	@Before
+					pendingContactFactory);
-	public void setUp() {
-		contactManager = new ContactManagerImpl(db, keyManager,
-				identityManager, pendingContactFactory);
-	}
 
 	@Test
 	public void testAddContact() throws Exception {

bramble-core/src/test/java/org/briarproject/bramble/data/BdfWriterImplTest.java

@@ -2,7 +2,6 @@ package org.briarproject.bramble.data;
 
 import org.briarproject.bramble.test.BrambleTestCase;
 import org.briarproject.bramble.util.StringUtils;
-import org.junit.Before;
 import org.junit.Test;
 
 import java.io.ByteArrayOutputStream;
@@ -17,14 +16,8 @@ import static org.junit.Assert.assertArrayEquals;
 
 public class BdfWriterImplTest extends BrambleTestCase {
 
-	private ByteArrayOutputStream out = null;
+	private final ByteArrayOutputStream out = new ByteArrayOutputStream();
-	private BdfWriterImpl w = null;
+	private final BdfWriterImpl w = new BdfWriterImpl(out);
-
-	@Before
-	public void setUp() {
-		out = new ByteArrayOutputStream();
-		w = new BdfWriterImpl(out);
-	}
 
 	@Test
 	public void testWriteNull() throws IOException {

bramble-core/src/test/java/org/briarproject/bramble/identity/IdentityManagerImplTest.java

@@ -14,7 +14,6 @@ import org.briarproject.bramble.api.system.Clock;
 import org.briarproject.bramble.test.BrambleMockTestCase;
 import org.briarproject.bramble.test.DbExpectations;
 import org.jmock.Expectations;
-import org.junit.Before;
 import org.junit.Test;
 
 import static java.util.Collections.singletonList;
@@ -41,13 +40,8 @@ public class IdentityManagerImplTest extends BrambleMockTestCase {
 	private final KeyPair handshakeKeyPair =
 			new KeyPair(handshakePublicKey, handshakePrivateKey);
 
-	private IdentityManagerImpl identityManager;
+	private final IdentityManagerImpl identityManager =
-
+			new IdentityManagerImpl(db, crypto, authorFactory, clock);
-	@Before
-	public void setUp() {
-		identityManager =
-				new IdentityManagerImpl(db, crypto, authorFactory, clock);
-	}
 
 	@Test
 	public void testOpenDatabaseIdentityRegistered() throws Exception {

bramble-core/src/test/java/org/briarproject/bramble/lifecycle/LifecycleManagerImplTest.java

@@ -10,7 +10,6 @@ import org.briarproject.bramble.api.system.Clock;
 import org.briarproject.bramble.test.BrambleMockTestCase;
 import org.briarproject.bramble.test.DbExpectations;
 import org.jmock.Expectations;
-import org.junit.Before;
 import org.junit.Test;
 
 import java.util.concurrent.atomic.AtomicBoolean;
@@ -34,12 +33,8 @@ public class LifecycleManagerImplTest extends BrambleMockTestCase {
 
 	private final SecretKey dbKey = getSecretKey();
 
-	private LifecycleManagerImpl lifecycleManager;
+	private final LifecycleManagerImpl lifecycleManager =
-
+			new LifecycleManagerImpl(db, eventBus, clock);
-	@Before
-	public void setUp() {
-		lifecycleManager = new LifecycleManagerImpl(db, eventBus, clock);
-	}
 
 	@Test
 	public void testOpenDatabaseHooksAreCalledAtStartup() throws Exception {

bramble-core/src/test/java/org/briarproject/bramble/mailbox/ContactMailboxClientTest.java

@@ -5,7 +5,6 @@ import org.briarproject.bramble.api.mailbox.MailboxFolderId;
 import org.briarproject.bramble.api.mailbox.MailboxProperties;
 import org.briarproject.bramble.test.BrambleMockTestCase;
 import org.jmock.Expectations;
-import org.junit.Before;
 import org.junit.Test;
 
 import static org.briarproject.bramble.api.mailbox.MailboxConstants.CLIENT_SUPPORTS;
@@ -34,13 +33,9 @@ public class ContactMailboxClientTest extends BrambleMockTestCase {
 			requireNonNull(properties.getOutboxId());
 	private final ContactId contactId = getContactId();
 
-	private ContactMailboxClient client;
+	private final ContactMailboxClient client =
-
+			new ContactMailboxClient(workerFactory, connectivityChecker,
-	@Before
+					reachabilityMonitor);
-	public void setUp() {
-		client = new ContactMailboxClient(workerFactory, connectivityChecker,
-				reachabilityMonitor);
-	}
 
 	@Test
 	public void testStartAndDestroyWithNoContactsAssigned() {

bramble-core/src/test/java/org/briarproject/bramble/mailbox/TorReachabilityMonitorImplTest.java

@@ -12,7 +12,6 @@ import org.briarproject.bramble.test.BrambleMockTestCase;
 import org.briarproject.bramble.test.CaptureArgumentAction;
 import org.jmock.Expectations;
 import org.jmock.lib.action.DoAllAction;
-import org.junit.Before;
 import org.junit.Test;
 
 import java.util.concurrent.Executor;
@@ -38,13 +37,9 @@ public class TorReachabilityMonitorImplTest extends BrambleMockTestCase {
 	private final TorReachabilityObserver observer =
 			context.mock(TorReachabilityObserver.class);
 
-	private TorReachabilityMonitorImpl monitor;
+	private final TorReachabilityMonitorImpl monitor =
-
+			new TorReachabilityMonitorImpl(ioExecutor, taskScheduler,
-	@Before
+					pluginManager, eventBus);
-	public void setUp() {
-		monitor = new TorReachabilityMonitorImpl(ioExecutor, taskScheduler,
-				pluginManager, eventBus);
-	}
 
 	@Test
 	public void testSchedulesTaskWhenStartedIfTorIsActive() {

bramble-core/src/test/java/org/briarproject/bramble/plugin/PollerImplTest.java

@@ -26,7 +26,6 @@ import org.briarproject.bramble.test.ImmediateExecutor;
 import org.briarproject.bramble.test.RunAction;
 import org.jmock.Expectations;
 import org.jmock.imposters.ByteBuddyClassImposteriser;
-import org.junit.Before;
 import org.junit.Test;
 
 import java.security.SecureRandom;
@@ -59,22 +58,18 @@ public class PollerImplTest extends BrambleMockTestCase {
 	private final SecureRandom random;
 
 	private final Executor ioExecutor = new ImmediateExecutor();
-	private final Executor wakefulIoExecutor = new ImmediateExecutor();
 	private final TransportId transportId = getTransportId();
 	private final ContactId contactId = getContactId();
 	private final TransportProperties properties = new TransportProperties();
 	private final int pollingInterval = 60 * 1000;
 	private final long now = System.currentTimeMillis();
 
-	private PollerImpl poller;
+	private final PollerImpl poller;
 
 	public PollerImplTest() {
 		context.setImposteriser(ByteBuddyClassImposteriser.INSTANCE);
 		random = context.mock(SecureRandom.class);
-	}
+		Executor wakefulIoExecutor = new ImmediateExecutor();
-
-	@Before
-	public void setUp() {
 		poller = new PollerImpl(ioExecutor, wakefulIoExecutor, scheduler,
 				connectionManager, connectionRegistry, pluginManager,
 				transportPropertyManager, random, clock);

bramble-core/src/test/java/org/briarproject/bramble/plugin/tcp/LanTcpPluginTest.java

@@ -12,7 +12,6 @@ import org.briarproject.bramble.api.plugin.duplex.DuplexTransportConnection;
 import org.briarproject.bramble.api.properties.TransportProperties;
 import org.briarproject.bramble.api.settings.Settings;
 import org.briarproject.bramble.test.BrambleTestCase;
-import org.junit.Before;
 import org.junit.Test;
 
 import java.io.IOException;
@@ -46,13 +45,11 @@ public class LanTcpPluginTest extends BrambleTestCase {
 
 	private final Backoff backoff = new TestBackoff();
 	private final ExecutorService ioExecutor = newCachedThreadPool();
+	private final Callback callback = new Callback();
 
-	private Callback callback = null;
+	private final LanTcpPlugin plugin;
-	private LanTcpPlugin plugin = null;
 
-	@Before
+	public LanTcpPluginTest() {
-	public void setUp() {
-		callback = new Callback();
 		plugin = new LanTcpPlugin(ioExecutor, ioExecutor, backoff, callback,
 				0, 0, 1000) {
 			@Override

bramble-core/src/test/java/org/briarproject/bramble/rendezvous/RendezvousPollerImplTest.java

@@ -34,7 +34,6 @@ import org.briarproject.bramble.test.DbExpectations;
 import org.briarproject.bramble.test.ImmediateExecutor;
 import org.briarproject.bramble.test.PredicateMatcher;
 import org.jmock.Expectations;
-import org.junit.Before;
 import org.junit.Test;
 
 import java.util.Random;
@@ -93,14 +92,10 @@ public class RendezvousPollerImplTest extends BrambleMockTestCase {
 			getTransportProperties(3);
 	private final boolean alice = new Random().nextBoolean();
 
-	private RendezvousPollerImpl rendezvousPoller;
+	private final RendezvousPollerImpl rendezvousPoller =
-
+			new RendezvousPollerImpl(ioExecutor, scheduler, db,
-	@Before
+					identityManager, transportCrypto, rendezvousCrypto,
-	public void setUp() {
+					pluginManager, connectionManager, eventBus, clock);
-		rendezvousPoller = new RendezvousPollerImpl(ioExecutor, scheduler, db,
-				identityManager, transportCrypto, rendezvousCrypto,
-				pluginManager, connectionManager, eventBus, clock);
-	}
 
 	@Test
 	public void testAddsPendingContactsAndSchedulesPollingAtStartup()

bramble-core/src/test/java/org/briarproject/bramble/sync/SyncRecordReaderImplTest.java

@@ -14,7 +14,6 @@ import org.briarproject.bramble.api.sync.SyncRecordReader;
 import org.briarproject.bramble.api.sync.Versions;
 import org.briarproject.bramble.test.BrambleMockTestCase;
 import org.jmock.Expectations;
-import org.junit.Before;
 import org.junit.Test;
 
 import java.io.ByteArrayOutputStream;
@@ -44,12 +43,8 @@ public class SyncRecordReaderImplTest extends BrambleMockTestCase {
 			context.mock(MessageFactory.class);
 	private final RecordReader recordReader = context.mock(RecordReader.class);
 
-	private SyncRecordReader reader;
+	private final SyncRecordReader reader =
-
+			new SyncRecordReaderImpl(messageFactory, recordReader);
-	@Before
-	public void setUp() {
-		reader = new SyncRecordReaderImpl(messageFactory, recordReader);
-	}
 
 	@Test
 	public void testNoFormatExceptionIfAckIsMaximumSize() throws Exception {

bramble-core/src/test/java/org/briarproject/bramble/sync/validation/ValidationManagerImplTest.java

@@ -20,7 +20,6 @@ import org.briarproject.bramble.api.sync.validation.MessageValidator;
 import org.briarproject.bramble.test.BrambleMockTestCase;
 import org.briarproject.bramble.test.DbExpectations;
 import org.briarproject.bramble.test.ImmediateExecutor;
-import org.junit.Before;
 import org.junit.Test;
 
 import java.util.LinkedHashMap;
@@ -70,11 +69,10 @@ public class ValidationManagerImplTest extends BrambleMockTestCase {
 	private final MessageContext validResultWithDependencies =
 			new MessageContext(metadata, singletonList(messageId1));
 
-	private ValidationManagerImpl vm;
+	private final ValidationManagerImpl vm =
+			new ValidationManagerImpl(db, dbExecutor, validationExecutor);
 
-	@Before
+	public ValidationManagerImplTest() {
-	public void setUp() {
-		vm = new ValidationManagerImpl(db, dbExecutor, validationExecutor);
 		vm.registerMessageValidator(clientId, majorVersion, validator);
 		vm.registerIncomingMessageHook(clientId, majorVersion, hook);
 	}

bramble-core/src/test/java/org/briarproject/bramble/transport/TransportKeyManagerImplTest.java

@@ -22,7 +22,6 @@ import org.hamcrest.Description;
 import org.jmock.Expectations;
 import org.jmock.api.Action;
 import org.jmock.api.Invocation;
-import org.junit.Before;
 import org.junit.Test;
 
 import java.util.ArrayList;
@@ -72,13 +71,9 @@ public class TransportKeyManagerImplTest extends BrambleMockTestCase {
 	private final SecretKey rootKey = getSecretKey();
 	private final Random random = new Random();
 
-	private TransportKeyManager transportKeyManager;
+	private final TransportKeyManager transportKeyManager =
-
+			new TransportKeyManagerImpl(db, transportCrypto, dbExecutor,
-	@Before
+					scheduler, clock, transportId, maxLatency);
-	public void setUp() {
-		transportKeyManager = new TransportKeyManagerImpl(db, transportCrypto,
-				dbExecutor, scheduler, clock, transportId, maxLatency);
-	}
 
 	@Test
 	public void testKeysAreUpdatedAtStartup() throws Exception {

bramble-java/src/test/java/org/briarproject/bramble/plugin/modem/ModemPluginTest.java

@@ -4,7 +4,6 @@ import org.briarproject.bramble.api.plugin.PluginCallback;
 import org.briarproject.bramble.api.properties.TransportProperties;
 import org.briarproject.bramble.test.BrambleMockTestCase;
 import org.jmock.Expectations;
-import org.junit.Before;
 import org.junit.Test;
 
 import java.io.IOException;
@@ -25,12 +24,8 @@ public class ModemPluginTest extends BrambleMockTestCase {
 	private final PluginCallback callback = context.mock(PluginCallback.class);
 	private final Modem modem = context.mock(Modem.class);
 
-	private ModemPlugin plugin;
+	private final ModemPlugin plugin =
-
+			new ModemPlugin(modemFactory, serialPortList, callback, 0);
-	@Before
-	public void setUp() {
-		plugin = new ModemPlugin(modemFactory, serialPortList, callback, 0);
-	}
 
 	@Test
 	public void testModemCreation() throws Exception {