Use null safety library.

2026-02-14 19:59:05 +01:00 · 2022-09-29 13:08:02 +01:00
parent 559138c5b6
commit e4e7d84bde
1037 changed files with 1244 additions and 1402 deletions
--- a/bramble-core/src/main/java/org/briarproject/bramble/PoliteExecutor.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/PoliteExecutor.java
@@ -1,6 +1,6 @@
 package org.briarproject.bramble;

-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.util.LinkedList;
 import java.util.Queue;
--- a/bramble-core/src/main/java/org/briarproject/bramble/TimeLoggingExecutor.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/TimeLoggingExecutor.java
@@ -1,6 +1,6 @@
 package org.briarproject.bramble;

-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.util.concurrent.BlockingQueue;
 import java.util.concurrent.RejectedExecutionHandler;
--- a/bramble-core/src/main/java/org/briarproject/bramble/account/AccountManagerImpl.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/account/AccountManagerImpl.java
@@ -9,9 +9,9 @@ import org.briarproject.bramble.api.crypto.SecretKey;
 import org.briarproject.bramble.api.db.DatabaseConfig;
 import org.briarproject.bramble.api.identity.Identity;
 import org.briarproject.bramble.api.identity.IdentityManager;
-import org.briarproject.bramble.api.nullsafety.MethodsNotNullByDefault;
-import org.briarproject.bramble.api.nullsafety.ParametersNotNullByDefault;
 import org.briarproject.bramble.util.IoUtils;
+import org.briarproject.nullsafety.MethodsNotNullByDefault;
+import org.briarproject.nullsafety.ParametersNotNullByDefault;

 import java.io.BufferedReader;
 import java.io.File;
--- a/bramble-core/src/main/java/org/briarproject/bramble/cleanup/CleanupManagerImpl.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/cleanup/CleanupManagerImpl.java
@@ -10,7 +10,6 @@ import org.briarproject.bramble.api.db.Transaction;
 import org.briarproject.bramble.api.event.Event;
 import org.briarproject.bramble.api.event.EventListener;
 import org.briarproject.bramble.api.lifecycle.Service;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.sync.ClientId;
 import org.briarproject.bramble.api.sync.Group;
 import org.briarproject.bramble.api.sync.GroupId;
@@ -18,6 +17,7 @@ import org.briarproject.bramble.api.sync.MessageId;
 import org.briarproject.bramble.api.system.Clock;
 import org.briarproject.bramble.api.system.TaskScheduler;
 import org.briarproject.bramble.api.versioning.ClientMajorVersion;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.util.Collection;
 import java.util.HashSet;
--- a/bramble-core/src/main/java/org/briarproject/bramble/client/ClientHelperImpl.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/client/ClientHelperImpl.java
@@ -29,7 +29,6 @@ import org.briarproject.bramble.api.mailbox.MailboxProperties;
 import org.briarproject.bramble.api.mailbox.MailboxUpdate;
 import org.briarproject.bramble.api.mailbox.MailboxUpdateWithMailbox;
 import org.briarproject.bramble.api.mailbox.MailboxVersion;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.plugin.TransportId;
 import org.briarproject.bramble.api.properties.TransportProperties;
 import org.briarproject.bramble.api.sync.GroupId;
@@ -37,6 +36,7 @@ import org.briarproject.bramble.api.sync.Message;
 import org.briarproject.bramble.api.sync.MessageFactory;
 import org.briarproject.bramble.api.sync.MessageId;
 import org.briarproject.bramble.util.Base32;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.io.ByteArrayInputStream;
 import java.io.ByteArrayOutputStream;
--- a/bramble-core/src/main/java/org/briarproject/bramble/client/ContactGroupFactoryImpl.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/client/ContactGroupFactoryImpl.java
@@ -6,10 +6,10 @@ import org.briarproject.bramble.api.client.ContactGroupFactory;
 import org.briarproject.bramble.api.contact.Contact;
 import org.briarproject.bramble.api.data.BdfList;
 import org.briarproject.bramble.api.identity.AuthorId;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.sync.ClientId;
 import org.briarproject.bramble.api.sync.Group;
 import org.briarproject.bramble.api.sync.GroupFactory;
+import org.briarproject.nullsafety.NotNullByDefault;

 import javax.annotation.concurrent.Immutable;
 import javax.inject.Inject;
--- a/bramble-core/src/main/java/org/briarproject/bramble/connection/Connection.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/connection/Connection.java
@@ -2,7 +2,6 @@ package org.briarproject.bramble.connection;

 import org.briarproject.bramble.api.connection.ConnectionRegistry;
 import org.briarproject.bramble.api.db.DbException;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.plugin.TransportConnectionReader;
 import org.briarproject.bramble.api.plugin.TransportConnectionWriter;
 import org.briarproject.bramble.api.plugin.TransportId;
@@ -10,6 +9,7 @@ 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 org.briarproject.nullsafety.NotNullByDefault;

 import java.io.IOException;
 import java.io.InputStream;
--- a/bramble-core/src/main/java/org/briarproject/bramble/connection/ConnectionManagerImpl.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/connection/ConnectionManagerImpl.java
@@ -7,7 +7,6 @@ import org.briarproject.bramble.api.contact.ContactId;
 import org.briarproject.bramble.api.contact.HandshakeManager;
 import org.briarproject.bramble.api.contact.PendingContactId;
 import org.briarproject.bramble.api.lifecycle.IoExecutor;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.plugin.TransportConnectionReader;
 import org.briarproject.bramble.api.plugin.TransportConnectionWriter;
 import org.briarproject.bramble.api.plugin.TransportId;
@@ -18,6 +17,7 @@ import org.briarproject.bramble.api.sync.SyncSessionFactory;
 import org.briarproject.bramble.api.transport.KeyManager;
 import org.briarproject.bramble.api.transport.StreamReaderFactory;
 import org.briarproject.bramble.api.transport.StreamWriterFactory;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.security.SecureRandom;
 import java.util.concurrent.Executor;
--- a/bramble-core/src/main/java/org/briarproject/bramble/connection/ConnectionRegistryImpl.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/connection/ConnectionRegistryImpl.java
@@ -6,7 +6,6 @@ import org.briarproject.bramble.api.connection.InterruptibleConnection;
 import org.briarproject.bramble.api.contact.ContactId;
 import org.briarproject.bramble.api.contact.PendingContactId;
 import org.briarproject.bramble.api.event.EventBus;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.plugin.PluginConfig;
 import org.briarproject.bramble.api.plugin.TransportId;
 import org.briarproject.bramble.api.plugin.event.ConnectionClosedEvent;
@@ -16,6 +15,7 @@ import org.briarproject.bramble.api.plugin.event.ContactDisconnectedEvent;
 import org.briarproject.bramble.api.rendezvous.event.RendezvousConnectionClosedEvent;
 import org.briarproject.bramble.api.rendezvous.event.RendezvousConnectionOpenedEvent;
 import org.briarproject.bramble.api.sync.Priority;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.util.ArrayList;
 import java.util.Collection;
--- a/bramble-core/src/main/java/org/briarproject/bramble/connection/DuplexSyncConnection.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/connection/DuplexSyncConnection.java
@@ -3,7 +3,6 @@ package org.briarproject.bramble.connection;
 import org.briarproject.bramble.api.connection.ConnectionRegistry;
 import org.briarproject.bramble.api.connection.InterruptibleConnection;
 import org.briarproject.bramble.api.contact.ContactId;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.plugin.TransportConnectionReader;
 import org.briarproject.bramble.api.plugin.TransportConnectionWriter;
 import org.briarproject.bramble.api.plugin.TransportId;
@@ -18,6 +17,7 @@ import org.briarproject.bramble.api.transport.StreamContext;
 import org.briarproject.bramble.api.transport.StreamReaderFactory;
 import org.briarproject.bramble.api.transport.StreamWriter;
 import org.briarproject.bramble.api.transport.StreamWriterFactory;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.io.IOException;
 import java.util.concurrent.Executor;
@@ -25,7 +25,7 @@ import java.util.concurrent.Executor;
 import javax.annotation.Nullable;
 import javax.annotation.concurrent.GuardedBy;

-import static org.briarproject.bramble.api.nullsafety.NullSafety.requireNonNull;
+import static org.briarproject.nullsafety.NullSafety.requireNonNull;

@NotNullByDefault
 abstract class DuplexSyncConnection extends SyncConnection
--- a/bramble-core/src/main/java/org/briarproject/bramble/connection/HandshakeConnection.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/connection/HandshakeConnection.java
@@ -6,7 +6,6 @@ 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.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.plugin.TransportConnectionReader;
 import org.briarproject.bramble.api.plugin.TransportConnectionWriter;
 import org.briarproject.bramble.api.plugin.TransportId;
@@ -15,6 +14,7 @@ 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 org.briarproject.nullsafety.NotNullByDefault;

 import javax.annotation.Nullable;

--- a/bramble-core/src/main/java/org/briarproject/bramble/connection/IncomingDuplexSyncConnection.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/connection/IncomingDuplexSyncConnection.java
@@ -3,7 +3,6 @@ package org.briarproject.bramble.connection;
 import org.briarproject.bramble.api.connection.ConnectionRegistry;
 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.TransportId;
 import org.briarproject.bramble.api.plugin.duplex.DuplexTransportConnection;
 import org.briarproject.bramble.api.properties.TransportPropertyManager;
@@ -14,6 +13,7 @@ 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 org.briarproject.nullsafety.NotNullByDefault;

 import java.io.IOException;
 import java.util.concurrent.Executor;
--- a/bramble-core/src/main/java/org/briarproject/bramble/connection/IncomingHandshakeConnection.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/connection/IncomingHandshakeConnection.java
@@ -7,7 +7,6 @@ import org.briarproject.bramble.api.contact.HandshakeManager;
 import org.briarproject.bramble.api.contact.HandshakeManager.HandshakeResult;
 import org.briarproject.bramble.api.contact.PendingContactId;
 import org.briarproject.bramble.api.db.DbException;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.plugin.TransportId;
 import org.briarproject.bramble.api.plugin.duplex.DuplexTransportConnection;
 import org.briarproject.bramble.api.transport.KeyManager;
@@ -15,6 +14,7 @@ import org.briarproject.bramble.api.transport.StreamContext;
 import org.briarproject.bramble.api.transport.StreamReaderFactory;
 import org.briarproject.bramble.api.transport.StreamWriter;
 import org.briarproject.bramble.api.transport.StreamWriterFactory;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.io.IOException;
 import java.io.InputStream;
--- a/bramble-core/src/main/java/org/briarproject/bramble/connection/IncomingSimplexSyncConnection.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/connection/IncomingSimplexSyncConnection.java
@@ -4,7 +4,6 @@ import org.briarproject.bramble.api.connection.ConnectionManager.TagController;
 import org.briarproject.bramble.api.connection.ConnectionRegistry;
 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.TransportConnectionReader;
 import org.briarproject.bramble.api.plugin.TransportId;
 import org.briarproject.bramble.api.properties.TransportPropertyManager;
@@ -14,6 +13,7 @@ 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 org.briarproject.nullsafety.NotNullByDefault;

 import java.io.IOException;

--- a/bramble-core/src/main/java/org/briarproject/bramble/connection/OutgoingDuplexSyncConnection.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/connection/OutgoingDuplexSyncConnection.java
@@ -3,7 +3,6 @@ package org.briarproject.bramble.connection;
 import org.briarproject.bramble.api.connection.ConnectionRegistry;
 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.TransportId;
 import org.briarproject.bramble.api.plugin.duplex.DuplexTransportConnection;
 import org.briarproject.bramble.api.properties.TransportPropertyManager;
@@ -15,6 +14,7 @@ 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 org.briarproject.nullsafety.NotNullByDefault;

 import java.io.IOException;
 import java.security.SecureRandom;
--- a/bramble-core/src/main/java/org/briarproject/bramble/connection/OutgoingHandshakeConnection.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/connection/OutgoingHandshakeConnection.java
@@ -8,7 +8,6 @@ import org.briarproject.bramble.api.contact.HandshakeManager;
 import org.briarproject.bramble.api.contact.HandshakeManager.HandshakeResult;
 import org.briarproject.bramble.api.contact.PendingContactId;
 import org.briarproject.bramble.api.db.DbException;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.plugin.TransportId;
 import org.briarproject.bramble.api.plugin.duplex.DuplexTransportConnection;
 import org.briarproject.bramble.api.transport.KeyManager;
@@ -16,6 +15,7 @@ import org.briarproject.bramble.api.transport.StreamContext;
 import org.briarproject.bramble.api.transport.StreamReaderFactory;
 import org.briarproject.bramble.api.transport.StreamWriter;
 import org.briarproject.bramble.api.transport.StreamWriterFactory;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.io.IOException;
 import java.io.InputStream;
--- a/bramble-core/src/main/java/org/briarproject/bramble/connection/OutgoingSimplexSyncConnection.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/connection/OutgoingSimplexSyncConnection.java
@@ -2,7 +2,6 @@ package org.briarproject.bramble.connection;

 import org.briarproject.bramble.api.connection.ConnectionRegistry;
 import org.briarproject.bramble.api.contact.ContactId;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.plugin.TransportConnectionWriter;
 import org.briarproject.bramble.api.plugin.TransportId;
 import org.briarproject.bramble.api.properties.TransportPropertyManager;
@@ -14,14 +13,15 @@ import org.briarproject.bramble.api.transport.StreamContext;
 import org.briarproject.bramble.api.transport.StreamReaderFactory;
 import org.briarproject.bramble.api.transport.StreamWriter;
 import org.briarproject.bramble.api.transport.StreamWriterFactory;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.io.IOException;

 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;
+import static org.briarproject.nullsafety.NullSafety.requireNonNull;

@NotNullByDefault
 class OutgoingSimplexSyncConnection extends SyncConnection implements Runnable {
--- a/bramble-core/src/main/java/org/briarproject/bramble/connection/SyncConnection.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/connection/SyncConnection.java
@@ -3,7 +3,6 @@ package org.briarproject.bramble.connection;
 import org.briarproject.bramble.api.connection.ConnectionRegistry;
 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.TransportConnectionReader;
 import org.briarproject.bramble.api.plugin.TransportId;
 import org.briarproject.bramble.api.properties.TransportPropertyManager;
@@ -14,6 +13,7 @@ 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 org.briarproject.nullsafety.NotNullByDefault;

 import java.io.IOException;
 import java.io.InputStream;
@@ -21,8 +21,8 @@ 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;
+import static org.briarproject.nullsafety.NullSafety.requireNonNull;

@NotNullByDefault
 class SyncConnection extends Connection {
--- a/bramble-core/src/main/java/org/briarproject/bramble/contact/ContactExchangeCrypto.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/contact/ContactExchangeCrypto.java
@@ -3,7 +3,7 @@ package org.briarproject.bramble.contact;
 import org.briarproject.bramble.api.crypto.PrivateKey;
 import org.briarproject.bramble.api.crypto.PublicKey;
 import org.briarproject.bramble.api.crypto.SecretKey;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.nullsafety.NotNullByDefault;

@NotNullByDefault
 interface ContactExchangeCrypto {
--- a/bramble-core/src/main/java/org/briarproject/bramble/contact/ContactExchangeCryptoImpl.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/contact/ContactExchangeCryptoImpl.java
@@ -4,7 +4,7 @@ import org.briarproject.bramble.api.crypto.CryptoComponent;
 import org.briarproject.bramble.api.crypto.PrivateKey;
 import org.briarproject.bramble.api.crypto.PublicKey;
 import org.briarproject.bramble.api.crypto.SecretKey;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.security.GeneralSecurityException;

--- a/bramble-core/src/main/java/org/briarproject/bramble/contact/ContactExchangeManagerImpl.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/contact/ContactExchangeManagerImpl.java
@@ -18,7 +18,6 @@ import org.briarproject.bramble.api.db.Transaction;
 import org.briarproject.bramble.api.identity.Author;
 import org.briarproject.bramble.api.identity.IdentityManager;
 import org.briarproject.bramble.api.identity.LocalAuthor;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.plugin.TransportId;
 import org.briarproject.bramble.api.plugin.duplex.DuplexTransportConnection;
 import org.briarproject.bramble.api.properties.TransportProperties;
@@ -32,6 +31,7 @@ import org.briarproject.bramble.api.system.Clock;
 import org.briarproject.bramble.api.transport.StreamReaderFactory;
 import org.briarproject.bramble.api.transport.StreamWriter;
 import org.briarproject.bramble.api.transport.StreamWriterFactory;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.io.EOFException;
 import java.io.IOException;
--- a/bramble-core/src/main/java/org/briarproject/bramble/contact/ContactManagerImpl.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/contact/ContactManagerImpl.java
@@ -21,8 +21,8 @@ import org.briarproject.bramble.api.event.EventListener;
 import org.briarproject.bramble.api.identity.Author;
 import org.briarproject.bramble.api.identity.AuthorId;
 import org.briarproject.bramble.api.identity.IdentityManager;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.transport.KeyManager;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.security.GeneralSecurityException;
 import java.util.ArrayList;
--- a/bramble-core/src/main/java/org/briarproject/bramble/contact/HandshakeCrypto.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/contact/HandshakeCrypto.java
@@ -3,7 +3,7 @@ package org.briarproject.bramble.contact;
 import org.briarproject.bramble.api.crypto.KeyPair;
 import org.briarproject.bramble.api.crypto.PublicKey;
 import org.briarproject.bramble.api.crypto.SecretKey;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.security.GeneralSecurityException;

--- a/bramble-core/src/main/java/org/briarproject/bramble/contact/HandshakeCryptoImpl.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/contact/HandshakeCryptoImpl.java
@@ -4,7 +4,7 @@ import org.briarproject.bramble.api.crypto.CryptoComponent;
 import org.briarproject.bramble.api.crypto.KeyPair;
 import org.briarproject.bramble.api.crypto.PublicKey;
 import org.briarproject.bramble.api.crypto.SecretKey;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.security.GeneralSecurityException;

--- a/bramble-core/src/main/java/org/briarproject/bramble/contact/HandshakeManagerImpl.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/contact/HandshakeManagerImpl.java
@@ -16,13 +16,13 @@ import org.briarproject.bramble.api.db.DatabaseComponent;
 import org.briarproject.bramble.api.db.DbException;
 import org.briarproject.bramble.api.db.TransactionManager;
 import org.briarproject.bramble.api.identity.IdentityManager;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.record.Record;
 import org.briarproject.bramble.api.record.RecordReader;
 import org.briarproject.bramble.api.record.RecordReaderFactory;
 import org.briarproject.bramble.api.record.RecordWriter;
 import org.briarproject.bramble.api.record.RecordWriterFactory;
 import org.briarproject.bramble.api.transport.StreamWriter;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.io.EOFException;
 import java.io.IOException;
--- a/bramble-core/src/main/java/org/briarproject/bramble/crypto/AgreementKeyParser.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/crypto/AgreementKeyParser.java
@@ -5,7 +5,7 @@ import org.briarproject.bramble.api.crypto.AgreementPublicKey;
 import org.briarproject.bramble.api.crypto.KeyParser;
 import org.briarproject.bramble.api.crypto.PrivateKey;
 import org.briarproject.bramble.api.crypto.PublicKey;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.security.GeneralSecurityException;

--- a/bramble-core/src/main/java/org/briarproject/bramble/crypto/AsciiArmour.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/crypto/AsciiArmour.java
@@ -1,8 +1,8 @@
 package org.briarproject.bramble.crypto;

 import org.briarproject.bramble.api.FormatException;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.util.StringUtils;
+import org.briarproject.nullsafety.NotNullByDefault;

@NotNullByDefault
 class AsciiArmour {
--- a/bramble-core/src/main/java/org/briarproject/bramble/crypto/AuthenticatedCipher.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/crypto/AuthenticatedCipher.java
@@ -1,7 +1,7 @@
 package org.briarproject.bramble.crypto;

 import org.briarproject.bramble.api.crypto.SecretKey;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.security.GeneralSecurityException;

--- a/bramble-core/src/main/java/org/briarproject/bramble/crypto/CryptoComponentImpl.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/crypto/CryptoComponentImpl.java
@@ -21,11 +21,11 @@ import org.briarproject.bramble.api.crypto.PublicKey;
 import org.briarproject.bramble.api.crypto.SecretKey;
 import org.briarproject.bramble.api.crypto.SignaturePrivateKey;
 import org.briarproject.bramble.api.crypto.SignaturePublicKey;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.system.SecureRandomProvider;
 import org.briarproject.bramble.util.Base32;
 import org.briarproject.bramble.util.ByteUtils;
 import org.briarproject.bramble.util.StringUtils;
+import org.briarproject.nullsafety.NotNullByDefault;
 import org.whispersystems.curve25519.Curve25519;
 import org.whispersystems.curve25519.Curve25519KeyPair;

--- a/bramble-core/src/main/java/org/briarproject/bramble/crypto/EdSignature.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/crypto/EdSignature.java
@@ -10,7 +10,7 @@ import net.i2p.crypto.eddsa.spec.EdDSAPublicKeySpec;

 import org.briarproject.bramble.api.crypto.PrivateKey;
 import org.briarproject.bramble.api.crypto.PublicKey;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.security.GeneralSecurityException;
 import java.security.NoSuchAlgorithmException;
--- a/bramble-core/src/main/java/org/briarproject/bramble/crypto/FrameEncoder.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/crypto/FrameEncoder.java
@@ -1,7 +1,7 @@
 package org.briarproject.bramble.crypto;

-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.util.ByteUtils;
+import org.briarproject.nullsafety.NotNullByDefault;

 import static org.briarproject.bramble.api.transport.TransportConstants.FRAME_HEADER_PLAINTEXT_LENGTH;
 import static org.briarproject.bramble.api.transport.TransportConstants.FRAME_NONCE_LENGTH;
--- a/bramble-core/src/main/java/org/briarproject/bramble/crypto/MessageEncrypter.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/crypto/MessageEncrypter.java
@@ -31,8 +31,8 @@ import org.briarproject.bramble.api.crypto.KeyPair;
 import org.briarproject.bramble.api.crypto.KeyParser;
 import org.briarproject.bramble.api.crypto.PrivateKey;
 import org.briarproject.bramble.api.crypto.PublicKey;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.util.StringUtils;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.io.FileInputStream;
 import java.io.FileOutputStream;
--- a/bramble-core/src/main/java/org/briarproject/bramble/crypto/PasswordStrengthEstimatorImpl.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/crypto/PasswordStrengthEstimatorImpl.java
@@ -1,7 +1,7 @@
 package org.briarproject.bramble.crypto;

 import org.briarproject.bramble.api.crypto.PasswordStrengthEstimator;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.util.HashSet;

--- a/bramble-core/src/main/java/org/briarproject/bramble/crypto/Sec1KeyParser.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/crypto/Sec1KeyParser.java
@@ -8,7 +8,7 @@ import org.bouncycastle.math.ec.ECPoint;
 import org.briarproject.bramble.api.crypto.KeyParser;
 import org.briarproject.bramble.api.crypto.PrivateKey;
 import org.briarproject.bramble.api.crypto.PublicKey;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.math.BigInteger;
 import java.security.GeneralSecurityException;
--- a/bramble-core/src/main/java/org/briarproject/bramble/crypto/Sec1PrivateKey.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/crypto/Sec1PrivateKey.java
@@ -2,7 +2,7 @@ package org.briarproject.bramble.crypto;

 import org.bouncycastle.crypto.params.ECPrivateKeyParameters;
 import org.briarproject.bramble.api.crypto.PrivateKey;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.nullsafety.NotNullByDefault;

 import javax.annotation.concurrent.Immutable;

--- a/bramble-core/src/main/java/org/briarproject/bramble/crypto/Sec1PublicKey.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/crypto/Sec1PublicKey.java
@@ -2,7 +2,7 @@ package org.briarproject.bramble.crypto;

 import org.bouncycastle.crypto.params.ECPublicKeyParameters;
 import org.briarproject.bramble.api.crypto.PublicKey;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.nullsafety.NotNullByDefault;

 import javax.annotation.concurrent.Immutable;

--- a/bramble-core/src/main/java/org/briarproject/bramble/crypto/Sec1Utils.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/crypto/Sec1Utils.java
@@ -1,6 +1,6 @@
 package org.briarproject.bramble.crypto;

-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.nullsafety.NotNullByDefault;

@NotNullByDefault
 class Sec1Utils {
--- a/bramble-core/src/main/java/org/briarproject/bramble/crypto/Signature.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/crypto/Signature.java
@@ -2,7 +2,7 @@ package org.briarproject.bramble.crypto;

 import org.briarproject.bramble.api.crypto.PrivateKey;
 import org.briarproject.bramble.api.crypto.PublicKey;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.security.GeneralSecurityException;

--- a/bramble-core/src/main/java/org/briarproject/bramble/crypto/SignatureKeyParser.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/crypto/SignatureKeyParser.java
@@ -5,7 +5,7 @@ import org.briarproject.bramble.api.crypto.PrivateKey;
 import org.briarproject.bramble.api.crypto.PublicKey;
 import org.briarproject.bramble.api.crypto.SignaturePrivateKey;
 import org.briarproject.bramble.api.crypto.SignaturePublicKey;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.security.GeneralSecurityException;

--- a/bramble-core/src/main/java/org/briarproject/bramble/crypto/StreamDecrypterFactoryImpl.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/crypto/StreamDecrypterFactoryImpl.java
@@ -3,8 +3,8 @@ package org.briarproject.bramble.crypto;
 import org.briarproject.bramble.api.crypto.SecretKey;
 import org.briarproject.bramble.api.crypto.StreamDecrypter;
 import org.briarproject.bramble.api.crypto.StreamDecrypterFactory;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.transport.StreamContext;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.io.InputStream;

--- a/bramble-core/src/main/java/org/briarproject/bramble/crypto/StreamDecrypterImpl.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/crypto/StreamDecrypterImpl.java
@@ -3,8 +3,8 @@ package org.briarproject.bramble.crypto;
 import org.briarproject.bramble.api.FormatException;
 import org.briarproject.bramble.api.crypto.SecretKey;
 import org.briarproject.bramble.api.crypto.StreamDecrypter;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.util.ByteUtils;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.io.EOFException;
 import java.io.IOException;
--- a/bramble-core/src/main/java/org/briarproject/bramble/crypto/StreamEncrypterFactoryImpl.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/crypto/StreamEncrypterFactoryImpl.java
@@ -5,8 +5,8 @@ import org.briarproject.bramble.api.crypto.SecretKey;
 import org.briarproject.bramble.api.crypto.StreamEncrypter;
 import org.briarproject.bramble.api.crypto.StreamEncrypterFactory;
 import org.briarproject.bramble.api.crypto.TransportCrypto;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.transport.StreamContext;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.io.OutputStream;

--- a/bramble-core/src/main/java/org/briarproject/bramble/crypto/StreamEncrypterImpl.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/crypto/StreamEncrypterImpl.java
@@ -2,8 +2,8 @@ package org.briarproject.bramble.crypto;

 import org.briarproject.bramble.api.crypto.SecretKey;
 import org.briarproject.bramble.api.crypto.StreamEncrypter;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.util.ByteUtils;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.io.IOException;
 import java.io.OutputStream;
--- a/bramble-core/src/main/java/org/briarproject/bramble/crypto/XSalsa20Poly1305AuthenticatedCipher.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/crypto/XSalsa20Poly1305AuthenticatedCipher.java
@@ -7,7 +7,7 @@ import org.bouncycastle.crypto.macs.Poly1305;
 import org.bouncycastle.crypto.params.KeyParameter;
 import org.bouncycastle.crypto.params.ParametersWithIV;
 import org.briarproject.bramble.api.crypto.SecretKey;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.security.GeneralSecurityException;

--- a/bramble-core/src/main/java/org/briarproject/bramble/data/BdfReaderFactoryImpl.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/data/BdfReaderFactoryImpl.java
@@ -2,7 +2,7 @@ package org.briarproject.bramble.data;

 import org.briarproject.bramble.api.data.BdfReader;
 import org.briarproject.bramble.api.data.BdfReaderFactory;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.io.InputStream;

--- a/bramble-core/src/main/java/org/briarproject/bramble/data/BdfReaderImpl.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/data/BdfReaderImpl.java
@@ -4,7 +4,7 @@ import org.briarproject.bramble.api.FormatException;
 import org.briarproject.bramble.api.data.BdfDictionary;
 import org.briarproject.bramble.api.data.BdfList;
 import org.briarproject.bramble.api.data.BdfReader;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.io.IOException;
 import java.io.InputStream;
--- a/bramble-core/src/main/java/org/briarproject/bramble/data/BdfWriterFactoryImpl.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/data/BdfWriterFactoryImpl.java
@@ -2,7 +2,7 @@ package org.briarproject.bramble.data;

 import org.briarproject.bramble.api.data.BdfWriter;
 import org.briarproject.bramble.api.data.BdfWriterFactory;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.io.OutputStream;

--- a/bramble-core/src/main/java/org/briarproject/bramble/data/BdfWriterImpl.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/data/BdfWriterImpl.java
@@ -3,7 +3,7 @@ package org.briarproject.bramble.data;
 import org.briarproject.bramble.api.Bytes;
 import org.briarproject.bramble.api.FormatException;
 import org.briarproject.bramble.api.data.BdfWriter;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.io.IOException;
 import java.io.OutputStream;
--- a/bramble-core/src/main/java/org/briarproject/bramble/data/MetadataEncoderImpl.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/data/MetadataEncoderImpl.java
@@ -7,7 +7,7 @@ import org.briarproject.bramble.api.data.BdfWriter;
 import org.briarproject.bramble.api.data.BdfWriterFactory;
 import org.briarproject.bramble.api.data.MetadataEncoder;
 import org.briarproject.bramble.api.db.Metadata;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.io.ByteArrayOutputStream;
 import java.io.IOException;
--- a/bramble-core/src/main/java/org/briarproject/bramble/data/MetadataParserImpl.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/data/MetadataParserImpl.java
@@ -6,7 +6,7 @@ import org.briarproject.bramble.api.data.BdfReader;
 import org.briarproject.bramble.api.data.BdfReaderFactory;
 import org.briarproject.bramble.api.data.MetadataParser;
 import org.briarproject.bramble.api.db.Metadata;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.io.ByteArrayInputStream;
 import java.io.IOException;
--- a/bramble-core/src/main/java/org/briarproject/bramble/db/Database.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/db/Database.java
@@ -17,7 +17,6 @@ import org.briarproject.bramble.api.db.MigrationListener;
 import org.briarproject.bramble.api.identity.Author;
 import org.briarproject.bramble.api.identity.AuthorId;
 import org.briarproject.bramble.api.identity.Identity;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.plugin.TransportId;
 import org.briarproject.bramble.api.settings.Settings;
 import org.briarproject.bramble.api.sync.ClientId;
@@ -31,6 +30,7 @@ import org.briarproject.bramble.api.sync.validation.MessageState;
 import org.briarproject.bramble.api.transport.KeySetId;
 import org.briarproject.bramble.api.transport.TransportKeySet;
 import org.briarproject.bramble.api.transport.TransportKeys;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.util.Collection;
 import java.util.List;
--- a/bramble-core/src/main/java/org/briarproject/bramble/db/DatabaseComponentImpl.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/db/DatabaseComponentImpl.java
@@ -42,7 +42,6 @@ import org.briarproject.bramble.api.identity.Identity;
 import org.briarproject.bramble.api.identity.event.IdentityAddedEvent;
 import org.briarproject.bramble.api.identity.event.IdentityRemovedEvent;
 import org.briarproject.bramble.api.lifecycle.ShutdownManager;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.plugin.TransportId;
 import org.briarproject.bramble.api.settings.Settings;
 import org.briarproject.bramble.api.settings.event.SettingsUpdatedEvent;
@@ -72,6 +71,7 @@ import org.briarproject.bramble.api.sync.validation.MessageState;
 import org.briarproject.bramble.api.transport.KeySetId;
 import org.briarproject.bramble.api.transport.TransportKeySet;
 import org.briarproject.bramble.api.transport.TransportKeys;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.util.ArrayList;
 import java.util.Collection;
--- a/bramble-core/src/main/java/org/briarproject/bramble/db/H2Database.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/db/H2Database.java
@@ -5,10 +5,10 @@ import org.briarproject.bramble.api.db.DatabaseConfig;
 import org.briarproject.bramble.api.db.DbClosedException;
 import org.briarproject.bramble.api.db.DbException;
 import org.briarproject.bramble.api.db.MigrationListener;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.sync.MessageFactory;
 import org.briarproject.bramble.api.system.Clock;
 import org.briarproject.bramble.util.StringUtils;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.io.File;
 import java.sql.Connection;
--- a/bramble-core/src/main/java/org/briarproject/bramble/db/HyperSqlDatabase.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/db/HyperSqlDatabase.java
@@ -5,10 +5,10 @@ import org.briarproject.bramble.api.db.DatabaseConfig;
 import org.briarproject.bramble.api.db.DbClosedException;
 import org.briarproject.bramble.api.db.DbException;
 import org.briarproject.bramble.api.db.MigrationListener;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.sync.MessageFactory;
 import org.briarproject.bramble.api.system.Clock;
 import org.briarproject.bramble.util.StringUtils;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.io.File;
 import java.sql.Connection;
--- a/bramble-core/src/main/java/org/briarproject/bramble/db/JdbcDatabase.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/db/JdbcDatabase.java
@@ -22,7 +22,6 @@ import org.briarproject.bramble.api.identity.Author;
 import org.briarproject.bramble.api.identity.AuthorId;
 import org.briarproject.bramble.api.identity.Identity;
 import org.briarproject.bramble.api.identity.LocalAuthor;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.plugin.TransportId;
 import org.briarproject.bramble.api.settings.Settings;
 import org.briarproject.bramble.api.sync.ClientId;
@@ -40,6 +39,7 @@ import org.briarproject.bramble.api.transport.KeySetId;
 import org.briarproject.bramble.api.transport.OutgoingKeys;
 import org.briarproject.bramble.api.transport.TransportKeySet;
 import org.briarproject.bramble.api.transport.TransportKeys;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.sql.Connection;
 import java.sql.PreparedStatement;
--- a/bramble-core/src/main/java/org/briarproject/bramble/db/JdbcUtils.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/db/JdbcUtils.java
@@ -1,6 +1,6 @@
 package org.briarproject.bramble.db;

-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.sql.Connection;
 import java.sql.ResultSet;
--- a/bramble-core/src/main/java/org/briarproject/bramble/event/EventBusImpl.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/event/EventBusImpl.java
@@ -4,7 +4,7 @@ import org.briarproject.bramble.api.event.Event;
 import org.briarproject.bramble.api.event.EventBus;
 import org.briarproject.bramble.api.event.EventExecutor;
 import org.briarproject.bramble.api.event.EventListener;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.util.Collection;
 import java.util.concurrent.CopyOnWriteArrayList;
--- a/bramble-core/src/main/java/org/briarproject/bramble/identity/AuthorFactoryImpl.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/identity/AuthorFactoryImpl.java
@@ -8,7 +8,7 @@ import org.briarproject.bramble.api.identity.Author;
 import org.briarproject.bramble.api.identity.AuthorFactory;
 import org.briarproject.bramble.api.identity.AuthorId;
 import org.briarproject.bramble.api.identity.LocalAuthor;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.nullsafety.NotNullByDefault;

 import javax.annotation.concurrent.Immutable;
 import javax.inject.Inject;
--- a/bramble-core/src/main/java/org/briarproject/bramble/identity/IdentityManagerImpl.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/identity/IdentityManagerImpl.java
@@ -12,8 +12,8 @@ import org.briarproject.bramble.api.identity.Identity;
 import org.briarproject.bramble.api.identity.IdentityManager;
 import org.briarproject.bramble.api.identity.LocalAuthor;
 import org.briarproject.bramble.api.lifecycle.LifecycleManager.OpenDatabaseHook;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.system.Clock;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.util.Collection;
 import java.util.logging.Logger;
@@ -23,9 +23,9 @@ import javax.annotation.concurrent.ThreadSafe;
 import javax.inject.Inject;

 import static java.util.logging.Logger.getLogger;
-import static org.briarproject.bramble.api.nullsafety.NullSafety.requireNonNull;
 import static org.briarproject.bramble.util.LogUtils.logDuration;
 import static org.briarproject.bramble.util.LogUtils.now;
+import static org.briarproject.nullsafety.NullSafety.requireNonNull;

@ThreadSafe
@NotNullByDefault
--- a/bramble-core/src/main/java/org/briarproject/bramble/io/NoDns.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/io/NoDns.java
@@ -1,6 +1,6 @@
 package org.briarproject.bramble.io;

-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.net.InetAddress;
 import java.net.UnknownHostException;
--- a/bramble-core/src/main/java/org/briarproject/bramble/io/TimeoutInputStream.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/io/TimeoutInputStream.java
@@ -1,7 +1,7 @@
 package org.briarproject.bramble.io;

-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.system.Clock;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.io.IOException;
 import java.io.InputStream;
--- a/bramble-core/src/main/java/org/briarproject/bramble/keyagreement/ConnectionChooserImpl.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/keyagreement/ConnectionChooserImpl.java
@@ -2,9 +2,9 @@ package org.briarproject.bramble.keyagreement;

 import org.briarproject.bramble.api.keyagreement.KeyAgreementConnection;
 import org.briarproject.bramble.api.lifecycle.IoExecutor;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.plugin.duplex.DuplexTransportConnection;
 import org.briarproject.bramble.api.system.Clock;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.io.IOException;
 import java.util.ArrayList;
--- a/bramble-core/src/main/java/org/briarproject/bramble/keyagreement/KeyAgreementConnector.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/keyagreement/KeyAgreementConnector.java
@@ -8,7 +8,6 @@ import org.briarproject.bramble.api.keyagreement.KeyAgreementConnection;
 import org.briarproject.bramble.api.keyagreement.KeyAgreementListener;
 import org.briarproject.bramble.api.keyagreement.Payload;
 import org.briarproject.bramble.api.keyagreement.TransportDescriptor;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.plugin.BluetoothConstants;
 import org.briarproject.bramble.api.plugin.LanTcpConstants;
 import org.briarproject.bramble.api.plugin.Plugin;
@@ -18,6 +17,7 @@ import org.briarproject.bramble.api.plugin.duplex.DuplexPlugin;
 import org.briarproject.bramble.api.plugin.duplex.DuplexTransportConnection;
 import org.briarproject.bramble.api.record.RecordReaderFactory;
 import org.briarproject.bramble.api.record.RecordWriterFactory;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.io.IOException;
 import java.io.InputStream;
--- a/bramble-core/src/main/java/org/briarproject/bramble/keyagreement/KeyAgreementProtocol.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/keyagreement/KeyAgreementProtocol.java
@@ -8,7 +8,7 @@ import org.briarproject.bramble.api.crypto.PublicKey;
 import org.briarproject.bramble.api.crypto.SecretKey;
 import org.briarproject.bramble.api.keyagreement.Payload;
 import org.briarproject.bramble.api.keyagreement.PayloadEncoder;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.io.IOException;
 import java.security.GeneralSecurityException;
--- a/bramble-core/src/main/java/org/briarproject/bramble/keyagreement/KeyAgreementTaskImpl.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/keyagreement/KeyAgreementTaskImpl.java
@@ -16,11 +16,11 @@ import org.briarproject.bramble.api.keyagreement.event.KeyAgreementListeningEven
 import org.briarproject.bramble.api.keyagreement.event.KeyAgreementStartedEvent;
 import org.briarproject.bramble.api.keyagreement.event.KeyAgreementStoppedListeningEvent;
 import org.briarproject.bramble.api.keyagreement.event.KeyAgreementWaitingEvent;
-import org.briarproject.bramble.api.nullsafety.MethodsNotNullByDefault;
-import org.briarproject.bramble.api.nullsafety.ParametersNotNullByDefault;
 import org.briarproject.bramble.api.plugin.PluginManager;
 import org.briarproject.bramble.api.record.RecordReaderFactory;
 import org.briarproject.bramble.api.record.RecordWriterFactory;
+import org.briarproject.nullsafety.MethodsNotNullByDefault;
+import org.briarproject.nullsafety.ParametersNotNullByDefault;

 import java.io.IOException;
 import java.util.logging.Logger;
--- a/bramble-core/src/main/java/org/briarproject/bramble/keyagreement/KeyAgreementTransport.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/keyagreement/KeyAgreementTransport.java
@@ -2,7 +2,6 @@ package org.briarproject.bramble.keyagreement;

 import org.briarproject.bramble.api.Predicate;
 import org.briarproject.bramble.api.keyagreement.KeyAgreementConnection;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.plugin.TransportId;
 import org.briarproject.bramble.api.plugin.duplex.DuplexTransportConnection;
 import org.briarproject.bramble.api.record.Record;
@@ -10,6 +9,7 @@ import org.briarproject.bramble.api.record.RecordReader;
 import org.briarproject.bramble.api.record.RecordReaderFactory;
 import org.briarproject.bramble.api.record.RecordWriter;
 import org.briarproject.bramble.api.record.RecordWriterFactory;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.io.EOFException;
 import java.io.IOException;
--- a/bramble-core/src/main/java/org/briarproject/bramble/keyagreement/PayloadEncoderImpl.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/keyagreement/PayloadEncoderImpl.java
@@ -5,7 +5,7 @@ import org.briarproject.bramble.api.data.BdfWriterFactory;
 import org.briarproject.bramble.api.keyagreement.Payload;
 import org.briarproject.bramble.api.keyagreement.PayloadEncoder;
 import org.briarproject.bramble.api.keyagreement.TransportDescriptor;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.io.ByteArrayOutputStream;
 import java.io.IOException;
--- a/bramble-core/src/main/java/org/briarproject/bramble/keyagreement/PayloadParserImpl.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/keyagreement/PayloadParserImpl.java
@@ -8,10 +8,10 @@ import org.briarproject.bramble.api.data.BdfReaderFactory;
 import org.briarproject.bramble.api.keyagreement.Payload;
 import org.briarproject.bramble.api.keyagreement.PayloadParser;
 import org.briarproject.bramble.api.keyagreement.TransportDescriptor;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.plugin.BluetoothConstants;
 import org.briarproject.bramble.api.plugin.LanTcpConstants;
 import org.briarproject.bramble.api.plugin.TransportId;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.io.ByteArrayInputStream;
 import java.io.IOException;
--- a/bramble-core/src/main/java/org/briarproject/bramble/lifecycle/LifecycleManagerImpl.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/lifecycle/LifecycleManagerImpl.java
@@ -11,8 +11,8 @@ import org.briarproject.bramble.api.lifecycle.LifecycleManager;
 import org.briarproject.bramble.api.lifecycle.Service;
 import org.briarproject.bramble.api.lifecycle.ServiceException;
 import org.briarproject.bramble.api.lifecycle.event.LifecycleEvent;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.system.Clock;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.util.List;
 import java.util.concurrent.CopyOnWriteArrayList;
--- a/bramble-core/src/main/java/org/briarproject/bramble/lifecycle/ShutdownManagerImpl.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/lifecycle/ShutdownManagerImpl.java
@@ -1,7 +1,7 @@
 package org.briarproject.bramble.lifecycle;

 import org.briarproject.bramble.api.lifecycle.ShutdownManager;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.util.HashMap;
 import java.util.Map;
--- a/bramble-core/src/main/java/org/briarproject/bramble/mailbox/ConnectivityChecker.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/mailbox/ConnectivityChecker.java
@@ -1,7 +1,7 @@
 package org.briarproject.bramble.mailbox;

 import org.briarproject.bramble.api.mailbox.MailboxProperties;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.nullsafety.NotNullByDefault;

 import javax.annotation.concurrent.ThreadSafe;

--- a/bramble-core/src/main/java/org/briarproject/bramble/mailbox/ConnectivityCheckerImpl.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/mailbox/ConnectivityCheckerImpl.java
@@ -2,8 +2,8 @@ package org.briarproject.bramble.mailbox;

 import org.briarproject.bramble.api.Cancellable;
 import org.briarproject.bramble.api.mailbox.MailboxProperties;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.system.Clock;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.util.ArrayList;
 import java.util.List;
--- a/bramble-core/src/main/java/org/briarproject/bramble/mailbox/ContactMailboxClient.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/mailbox/ContactMailboxClient.java
@@ -3,7 +3,7 @@ package org.briarproject.bramble.mailbox;
 import org.briarproject.bramble.api.contact.ContactId;
 import org.briarproject.bramble.api.mailbox.MailboxFolderId;
 import org.briarproject.bramble.api.mailbox.MailboxProperties;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.util.logging.Logger;

--- a/bramble-core/src/main/java/org/briarproject/bramble/mailbox/ContactMailboxConnectivityChecker.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/mailbox/ContactMailboxConnectivityChecker.java
@@ -1,9 +1,9 @@
 package org.briarproject.bramble.mailbox;

 import org.briarproject.bramble.api.mailbox.MailboxProperties;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.system.Clock;
 import org.briarproject.bramble.mailbox.MailboxApi.ApiException;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.util.logging.Logger;

--- a/bramble-core/src/main/java/org/briarproject/bramble/mailbox/ContactMailboxDownloadWorker.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/mailbox/ContactMailboxDownloadWorker.java
@@ -2,10 +2,10 @@ package org.briarproject.bramble.mailbox;

 import org.briarproject.bramble.api.mailbox.MailboxFolderId;
 import org.briarproject.bramble.api.mailbox.MailboxProperties;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.mailbox.MailboxApi.ApiException;
 import org.briarproject.bramble.mailbox.MailboxApi.MailboxFile;
 import org.briarproject.bramble.mailbox.MailboxApi.TolerableFailureException;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.io.IOException;
 import java.util.LinkedList;
@@ -15,7 +15,7 @@ import java.util.Queue;
 import javax.annotation.concurrent.ThreadSafe;

 import static java.util.Collections.emptyList;
-import static org.briarproject.bramble.api.nullsafety.NullSafety.requireNonNull;
+import static org.briarproject.nullsafety.NullSafety.requireNonNull;

@ThreadSafe
@NotNullByDefault
--- a/bramble-core/src/main/java/org/briarproject/bramble/mailbox/MailboxApi.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/mailbox/MailboxApi.java
@@ -8,7 +8,7 @@ import org.briarproject.bramble.api.mailbox.MailboxFileId;
 import org.briarproject.bramble.api.mailbox.MailboxFolderId;
 import org.briarproject.bramble.api.mailbox.MailboxProperties;
 import org.briarproject.bramble.api.mailbox.MailboxVersion;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.io.File;
 import java.io.IOException;
--- a/bramble-core/src/main/java/org/briarproject/bramble/mailbox/MailboxApiCaller.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/mailbox/MailboxApiCaller.java
@@ -2,7 +2,7 @@ package org.briarproject.bramble.mailbox;

 import org.briarproject.bramble.api.Cancellable;
 import org.briarproject.bramble.api.lifecycle.IoExecutor;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.nullsafety.NotNullByDefault;

 import static java.util.concurrent.TimeUnit.DAYS;
 import static java.util.concurrent.TimeUnit.MINUTES;
--- a/bramble-core/src/main/java/org/briarproject/bramble/mailbox/MailboxApiCallerImpl.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/mailbox/MailboxApiCallerImpl.java
@@ -2,8 +2,8 @@ package org.briarproject.bramble.mailbox;

 import org.briarproject.bramble.api.Cancellable;
 import org.briarproject.bramble.api.lifecycle.IoExecutor;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.system.TaskScheduler;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.util.concurrent.Executor;

--- a/bramble-core/src/main/java/org/briarproject/bramble/mailbox/MailboxApiImpl.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/mailbox/MailboxApiImpl.java
@@ -15,7 +15,7 @@ import org.briarproject.bramble.api.mailbox.MailboxFolderId;
 import org.briarproject.bramble.api.mailbox.MailboxId;
 import org.briarproject.bramble.api.mailbox.MailboxProperties;
 import org.briarproject.bramble.api.mailbox.MailboxVersion;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.io.File;
 import java.io.FileOutputStream;
--- a/bramble-core/src/main/java/org/briarproject/bramble/mailbox/MailboxClient.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/mailbox/MailboxClient.java
@@ -3,7 +3,7 @@ package org.briarproject.bramble.mailbox;
 import org.briarproject.bramble.api.contact.ContactId;
 import org.briarproject.bramble.api.mailbox.MailboxFolderId;
 import org.briarproject.bramble.api.mailbox.MailboxProperties;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.nullsafety.NotNullByDefault;

 import javax.annotation.concurrent.ThreadSafe;

--- a/bramble-core/src/main/java/org/briarproject/bramble/mailbox/MailboxClientFactory.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/mailbox/MailboxClientFactory.java
@@ -1,7 +1,7 @@
 package org.briarproject.bramble.mailbox;

 import org.briarproject.bramble.api.mailbox.MailboxProperties;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.nullsafety.NotNullByDefault;

@NotNullByDefault
 interface MailboxClientFactory {
--- a/bramble-core/src/main/java/org/briarproject/bramble/mailbox/MailboxClientFactoryImpl.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/mailbox/MailboxClientFactoryImpl.java
@@ -2,8 +2,8 @@ package org.briarproject.bramble.mailbox;

 import org.briarproject.bramble.api.lifecycle.IoExecutor;
 import org.briarproject.bramble.api.mailbox.MailboxProperties;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.system.TaskScheduler;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.util.concurrent.Executor;

--- a/bramble-core/src/main/java/org/briarproject/bramble/mailbox/MailboxClientManager.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/mailbox/MailboxClientManager.java
@@ -24,11 +24,11 @@ import org.briarproject.bramble.api.mailbox.event.MailboxUnpairedEvent;
 import org.briarproject.bramble.api.mailbox.event.MailboxUpdateSentToNewContactEvent;
 import org.briarproject.bramble.api.mailbox.event.OwnMailboxConnectionStatusEvent;
 import org.briarproject.bramble.api.mailbox.event.RemoteMailboxUpdateEvent;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.plugin.Plugin;
 import org.briarproject.bramble.api.plugin.PluginManager;
 import org.briarproject.bramble.api.plugin.event.TransportActiveEvent;
 import org.briarproject.bramble.api.plugin.event.TransportInactiveEvent;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.util.HashMap;
 import java.util.List;
@@ -47,10 +47,10 @@ import static java.util.logging.Level.WARNING;
 import static java.util.logging.Logger.getLogger;
 import static org.briarproject.bramble.api.mailbox.MailboxConstants.CLIENT_SUPPORTS;
 import static org.briarproject.bramble.api.mailbox.MailboxHelper.isClientCompatibleWithServer;
-import static org.briarproject.bramble.api.nullsafety.NullSafety.requireNonNull;
 import static org.briarproject.bramble.api.plugin.Plugin.State.ACTIVE;
 import static org.briarproject.bramble.api.plugin.TorConstants.ID;
 import static org.briarproject.bramble.util.LogUtils.logException;
+import static org.briarproject.nullsafety.NullSafety.requireNonNull;

 /**
 * This component manages a {@link MailboxClient} for each mailbox we know
--- a/bramble-core/src/main/java/org/briarproject/bramble/mailbox/MailboxDownloadWorker.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/mailbox/MailboxDownloadWorker.java
@@ -4,11 +4,11 @@ import org.briarproject.bramble.api.Cancellable;
 import org.briarproject.bramble.api.mailbox.MailboxFileId;
 import org.briarproject.bramble.api.mailbox.MailboxFolderId;
 import org.briarproject.bramble.api.mailbox.MailboxProperties;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.mailbox.ConnectivityChecker.ConnectivityObserver;
 import org.briarproject.bramble.mailbox.MailboxApi.ApiException;
 import org.briarproject.bramble.mailbox.MailboxApi.TolerableFailureException;
 import org.briarproject.bramble.mailbox.TorReachabilityMonitor.TorReachabilityObserver;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.io.File;
 import java.io.IOException;
--- a/bramble-core/src/main/java/org/briarproject/bramble/mailbox/MailboxFileManager.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/mailbox/MailboxFileManager.java
@@ -1,8 +1,8 @@
 package org.briarproject.bramble.mailbox;

 import org.briarproject.bramble.api.contact.ContactId;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.sync.OutgoingSessionRecord;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.io.File;
 import java.io.IOException;
--- a/bramble-core/src/main/java/org/briarproject/bramble/mailbox/MailboxFileManagerImpl.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/mailbox/MailboxFileManagerImpl.java
@@ -8,7 +8,6 @@ import org.briarproject.bramble.api.event.EventListener;
 import org.briarproject.bramble.api.lifecycle.IoExecutor;
 import org.briarproject.bramble.api.lifecycle.LifecycleManager;
 import org.briarproject.bramble.api.mailbox.MailboxDirectory;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.plugin.PluginManager;
 import org.briarproject.bramble.api.plugin.TransportConnectionReader;
 import org.briarproject.bramble.api.plugin.TransportConnectionWriter;
@@ -16,6 +15,7 @@ import org.briarproject.bramble.api.plugin.event.TransportActiveEvent;
 import org.briarproject.bramble.api.plugin.simplex.SimplexPlugin;
 import org.briarproject.bramble.api.properties.TransportProperties;
 import org.briarproject.bramble.api.sync.OutgoingSessionRecord;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.io.File;
 import java.io.IOException;
@@ -34,10 +34,10 @@ import static java.util.logging.Level.WARNING;
 import static java.util.logging.Logger.getLogger;
 import static org.briarproject.bramble.api.lifecycle.LifecycleManager.LifecycleState.RUNNING;
 import static org.briarproject.bramble.api.mailbox.MailboxConstants.ID;
-import static org.briarproject.bramble.api.nullsafety.NullSafety.requireNonNull;
 import static org.briarproject.bramble.api.plugin.file.FileConstants.PROP_PATH;
 import static org.briarproject.bramble.util.IoUtils.delete;
 import static org.briarproject.bramble.util.LogUtils.logException;
+import static org.briarproject.nullsafety.NullSafety.requireNonNull;

@ThreadSafe
@NotNullByDefault
--- a/bramble-core/src/main/java/org/briarproject/bramble/mailbox/MailboxManagerImpl.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/mailbox/MailboxManagerImpl.java
@@ -10,8 +10,8 @@ import org.briarproject.bramble.api.mailbox.MailboxProperties;
 import org.briarproject.bramble.api.mailbox.MailboxSettingsManager;
 import org.briarproject.bramble.api.mailbox.MailboxStatus;
 import org.briarproject.bramble.api.mailbox.MailboxVersion;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.system.Clock;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.io.IOException;
 import java.util.List;
--- a/bramble-core/src/main/java/org/briarproject/bramble/mailbox/MailboxPairingTaskFactory.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/mailbox/MailboxPairingTaskFactory.java
@@ -2,7 +2,7 @@ package org.briarproject.bramble.mailbox;


 import org.briarproject.bramble.api.mailbox.MailboxPairingTask;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.nullsafety.NotNullByDefault;

@NotNullByDefault
 interface MailboxPairingTaskFactory {
--- a/bramble-core/src/main/java/org/briarproject/bramble/mailbox/MailboxPairingTaskFactoryImpl.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/mailbox/MailboxPairingTaskFactoryImpl.java
@@ -6,8 +6,8 @@ import org.briarproject.bramble.api.event.EventExecutor;
 import org.briarproject.bramble.api.mailbox.MailboxPairingTask;
 import org.briarproject.bramble.api.mailbox.MailboxSettingsManager;
 import org.briarproject.bramble.api.mailbox.MailboxUpdateManager;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.system.Clock;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.util.concurrent.Executor;

--- a/bramble-core/src/main/java/org/briarproject/bramble/mailbox/MailboxPairingTaskImpl.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/mailbox/MailboxPairingTaskImpl.java
@@ -14,10 +14,10 @@ import org.briarproject.bramble.api.mailbox.MailboxProperties;
 import org.briarproject.bramble.api.mailbox.MailboxSettingsManager;
 import org.briarproject.bramble.api.mailbox.MailboxUpdate;
 import org.briarproject.bramble.api.mailbox.MailboxUpdateManager;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.system.Clock;
 import org.briarproject.bramble.mailbox.MailboxApi.ApiException;
 import org.briarproject.bramble.mailbox.MailboxApi.MailboxAlreadyPairedException;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.io.IOException;
 import java.nio.charset.Charset;
--- a/bramble-core/src/main/java/org/briarproject/bramble/mailbox/MailboxSettingsManagerImpl.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/mailbox/MailboxSettingsManagerImpl.java
@@ -11,9 +11,9 @@ import org.briarproject.bramble.api.mailbox.MailboxStatus;
 import org.briarproject.bramble.api.mailbox.MailboxVersion;
 import org.briarproject.bramble.api.mailbox.event.MailboxProblemEvent;
 import org.briarproject.bramble.api.mailbox.event.OwnMailboxConnectionStatusEvent;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.settings.Settings;
 import org.briarproject.bramble.api.settings.SettingsManager;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.util.ArrayList;
 import java.util.List;
--- a/bramble-core/src/main/java/org/briarproject/bramble/mailbox/MailboxUpdateManagerImpl.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/mailbox/MailboxUpdateManagerImpl.java
@@ -29,7 +29,6 @@ import org.briarproject.bramble.api.mailbox.event.MailboxPairedEvent;
 import org.briarproject.bramble.api.mailbox.event.MailboxUnpairedEvent;
 import org.briarproject.bramble.api.mailbox.event.MailboxUpdateSentToNewContactEvent;
 import org.briarproject.bramble.api.mailbox.event.RemoteMailboxUpdateEvent;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.sync.Group;
 import org.briarproject.bramble.api.sync.Group.Visibility;
 import org.briarproject.bramble.api.sync.GroupId;
@@ -40,6 +39,7 @@ import org.briarproject.bramble.api.sync.validation.IncomingMessageHook;
 import org.briarproject.bramble.api.system.Clock;
 import org.briarproject.bramble.api.versioning.ClientVersioningManager;
 import org.briarproject.bramble.api.versioning.ClientVersioningManager.ClientVersioningHook;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.util.HashMap;
 import java.util.List;
@@ -51,8 +51,8 @@ import javax.inject.Inject;

 import static java.util.Collections.emptyList;
 import static org.briarproject.bramble.api.data.BdfDictionary.NULL_VALUE;
-import static org.briarproject.bramble.api.nullsafety.NullSafety.requireNonNull;
 import static org.briarproject.bramble.api.sync.validation.IncomingMessageHook.DeliveryAction.ACCEPT_DO_NOT_SHARE;
+import static org.briarproject.nullsafety.NullSafety.requireNonNull;

@NotNullByDefault
 class MailboxUpdateManagerImpl implements MailboxUpdateManager,
--- a/bramble-core/src/main/java/org/briarproject/bramble/mailbox/MailboxUpdateValidator.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/mailbox/MailboxUpdateValidator.java
@@ -7,11 +7,11 @@ import org.briarproject.bramble.api.client.ClientHelper;
 import org.briarproject.bramble.api.data.BdfDictionary;
 import org.briarproject.bramble.api.data.BdfList;
 import org.briarproject.bramble.api.data.MetadataEncoder;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.sync.Group;
 import org.briarproject.bramble.api.sync.InvalidMessageException;
 import org.briarproject.bramble.api.sync.Message;
 import org.briarproject.bramble.api.system.Clock;
+import org.briarproject.nullsafety.NotNullByDefault;

 import javax.annotation.concurrent.Immutable;

--- a/bramble-core/src/main/java/org/briarproject/bramble/mailbox/MailboxUploadWorker.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/mailbox/MailboxUploadWorker.java
@@ -12,7 +12,6 @@ import org.briarproject.bramble.api.event.EventListener;
 import org.briarproject.bramble.api.lifecycle.IoExecutor;
 import org.briarproject.bramble.api.mailbox.MailboxFolderId;
 import org.briarproject.bramble.api.mailbox.MailboxProperties;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.plugin.event.ContactConnectedEvent;
 import org.briarproject.bramble.api.plugin.event.ContactDisconnectedEvent;
 import org.briarproject.bramble.api.sync.MessageId;
@@ -24,6 +23,7 @@ import org.briarproject.bramble.api.system.Clock;
 import org.briarproject.bramble.api.system.TaskScheduler;
 import org.briarproject.bramble.mailbox.ConnectivityChecker.ConnectivityObserver;
 import org.briarproject.bramble.mailbox.MailboxApi.ApiException;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.io.File;
 import java.io.IOException;
--- a/bramble-core/src/main/java/org/briarproject/bramble/mailbox/MailboxWorker.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/mailbox/MailboxWorker.java
@@ -1,6 +1,6 @@
 package org.briarproject.bramble.mailbox;

-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.nullsafety.NotNullByDefault;

 import javax.annotation.concurrent.ThreadSafe;

--- a/bramble-core/src/main/java/org/briarproject/bramble/mailbox/MailboxWorkerFactory.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/mailbox/MailboxWorkerFactory.java
@@ -3,7 +3,7 @@ package org.briarproject.bramble.mailbox;
 import org.briarproject.bramble.api.contact.ContactId;
 import org.briarproject.bramble.api.mailbox.MailboxFolderId;
 import org.briarproject.bramble.api.mailbox.MailboxProperties;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.nullsafety.NotNullByDefault;

 import javax.annotation.concurrent.ThreadSafe;

--- a/bramble-core/src/main/java/org/briarproject/bramble/mailbox/MailboxWorkerFactoryImpl.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/mailbox/MailboxWorkerFactoryImpl.java
@@ -8,9 +8,9 @@ import org.briarproject.bramble.api.lifecycle.IoExecutor;
 import org.briarproject.bramble.api.mailbox.MailboxFolderId;
 import org.briarproject.bramble.api.mailbox.MailboxProperties;
 import org.briarproject.bramble.api.mailbox.MailboxUpdateManager;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.system.Clock;
 import org.briarproject.bramble.api.system.TaskScheduler;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.util.concurrent.Executor;

--- a/bramble-core/src/main/java/org/briarproject/bramble/mailbox/OwnMailboxClient.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/mailbox/OwnMailboxClient.java
@@ -5,9 +5,9 @@ import org.briarproject.bramble.api.contact.ContactId;
 import org.briarproject.bramble.api.lifecycle.IoExecutor;
 import org.briarproject.bramble.api.mailbox.MailboxFolderId;
 import org.briarproject.bramble.api.mailbox.MailboxProperties;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.system.TaskScheduler;
 import org.briarproject.bramble.mailbox.ConnectivityChecker.ConnectivityObserver;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.util.ArrayList;
 import java.util.HashMap;
--- a/bramble-core/src/main/java/org/briarproject/bramble/mailbox/OwnMailboxConnectivityChecker.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/mailbox/OwnMailboxConnectivityChecker.java
@@ -5,9 +5,9 @@ import org.briarproject.bramble.api.db.TransactionManager;
 import org.briarproject.bramble.api.mailbox.MailboxProperties;
 import org.briarproject.bramble.api.mailbox.MailboxSettingsManager;
 import org.briarproject.bramble.api.mailbox.MailboxVersion;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.system.Clock;
 import org.briarproject.bramble.mailbox.MailboxApi.ApiException;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.io.IOException;
 import java.util.List;
--- a/bramble-core/src/main/java/org/briarproject/bramble/mailbox/OwnMailboxContactListWorker.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/mailbox/OwnMailboxContactListWorker.java
@@ -17,11 +17,11 @@ import org.briarproject.bramble.api.mailbox.MailboxProperties;
 import org.briarproject.bramble.api.mailbox.MailboxUpdate;
 import org.briarproject.bramble.api.mailbox.MailboxUpdateManager;
 import org.briarproject.bramble.api.mailbox.MailboxUpdateWithMailbox;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.mailbox.ConnectivityChecker.ConnectivityObserver;
 import org.briarproject.bramble.mailbox.MailboxApi.ApiException;
 import org.briarproject.bramble.mailbox.MailboxApi.MailboxContact;
 import org.briarproject.bramble.mailbox.MailboxApi.TolerableFailureException;
+import org.briarproject.nullsafety.NotNullByDefault;

 import java.io.IOException;
 import java.util.Collection;
@@ -39,8 +39,8 @@ import javax.annotation.concurrent.ThreadSafe;
 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.nullsafety.NullSafety.requireNonNull;
 import static org.briarproject.bramble.util.LogUtils.logException;
+import static org.briarproject.nullsafety.NullSafety.requireNonNull;

@ThreadSafe
@NotNullByDefault
--- a/Show More
+++ b/Show More