Java Code Examples for org.bitcoinj.core.Sha256Hash#of()

@Test
public void autosaveImmediate() throws Exception {
    // Test that the wallet will save itself automatically when it changes.
    File f = File.createTempFile("bitcoinj-unit-test", null);
    Sha256Hash hash1 = Sha256Hash.of(f);
    // Start with zero delay and ensure the wallet file changes after adding a key.
    wallet.autosaveToFile(f, 0, TimeUnit.SECONDS, null);
    ECKey key = wallet.freshReceiveKey();
    Sha256Hash hash2 = Sha256Hash.of(f);
    assertFalse("Wallet not saved after generating fresh key", hash1.equals(hash2));  // File has changed.

    Transaction t1 = createFakeTx(UNITTEST, valueOf(5, 0), key);
    if (wallet.isPendingTransactionRelevant(t1))
        wallet.receivePending(t1, null);
    Sha256Hash hash3 = Sha256Hash.of(f);
    assertFalse("Wallet not saved after receivePending", hash2.equals(hash3));  // File has changed again.
}
 

@Test
public void autosaveImmediate() throws Exception {
    // Test that the wallet will save itself automatically when it changes.
    File f = File.createTempFile("bitcoinj-unit-test", null);
    Sha256Hash hash1 = Sha256Hash.of(f);
    // Start with zero delay and ensure the wallet file changes after adding a key.
    wallet.autosaveToFile(f, 0, TimeUnit.SECONDS, null);
    ECKey key = wallet.freshReceiveKey();
    Sha256Hash hash2 = Sha256Hash.of(f);
    assertFalse("Wallet not saved after generating fresh key", hash1.equals(hash2));  // File has changed.

    Transaction t1 = createFakeTx(PARAMS, valueOf(5, 0), key);
    if (wallet.isPendingTransactionRelevant(t1))
        wallet.receivePending(t1, null);
    Sha256Hash hash3 = Sha256Hash.of(f);
    assertFalse("Wallet not saved after receivePending", hash2.equals(hash3));  // File has changed again.
}
 

@Test
public void autosaveImmediate() throws Exception {
    // Test that the wallet will save itself automatically when it changes.
    File f = File.createTempFile("bitcoinj-unit-test", null);
    Sha256Hash hash1 = Sha256Hash.of(f);
    // Start with zero delay and ensure the wallet file changes after adding a key.
    wallet.autosaveToFile(f, 0, TimeUnit.SECONDS, null);
    ECKey key = wallet.freshReceiveKey();
    Sha256Hash hash2 = Sha256Hash.of(f);
    assertFalse("Wallet not saved after generating fresh key", hash1.equals(hash2));  // File has changed.

    Transaction t1 = createFakeTx(PARAMS, valueOf(5, 0), key);
    if (wallet.isPendingTransactionRelevant(t1))
        wallet.receivePending(t1, null);
    Sha256Hash hash3 = Sha256Hash.of(f);
    assertFalse("Wallet not saved after receivePending", hash2.equals(hash3));  // File has changed again.
}
 

/**
 * Generate a bitcoin-style compact signature.
 *
 * @param privateKey ECKey private key
 * @param data the raw message bytes
 * @return the raw signature bytes
 */
private static byte[] generateCompactSig(final ECKey privateKey, final byte[] data) {
  Sha256Hash hash = Sha256Hash.of(data);
  ECKey.ECDSASignature sig = privateKey.sign(hash);

  byte[] csig = new byte[NUM_SIGNATURE_BYTES];

  System.arraycopy(Utils.bigIntegerToBytes(sig.r, HALF_NUM_SIGNATURE_BYTES), 0,
                                           csig, 0, HALF_NUM_SIGNATURE_BYTES);
  System.arraycopy(Utils.bigIntegerToBytes(sig.s, HALF_NUM_SIGNATURE_BYTES), 0,
                                           csig, HALF_NUM_SIGNATURE_BYTES, HALF_NUM_SIGNATURE_BYTES);

  return csig;
}
 

/**
 * Attempts to open a new connection to and open a payment channel with the given host and port, blocking until the
 * connection is open.  The server is requested to keep the channel open for {@code timeoutSeconds}
 * seconds. If the server proposes a longer time the channel will be closed.
 *
 * @param server                  The host/port pair where the server is listening.
 * @param timeoutSeconds          The connection timeout and read timeout during initialization. This should be large enough
 *                                to accommodate ECDSA signature operations and network latency.
 * @param wallet                  The wallet which will be paid from, and where completed transactions will be committed.
 *                                Can be encrypted if user key is supplied when needed. Must already have a
 *                                {@link StoredPaymentChannelClientStates} object in its extensions set.
 * @param myKey                   A freshly generated keypair used for the multisig contract and refund output.
 * @param maxValue                The maximum value this channel is allowed to request
 * @param serverId                A unique ID which is used to attempt reopening of an existing channel.
 *                                This must be unique to the server, and, if your application is exposing payment channels to some
 *                                API, this should also probably encompass some caller UID to avoid applications opening channels
 *                                which were created by others.
 * @param userKeySetup            Key derived from a user password, used to decrypt myKey, if it is encrypted, during setup.
 * @param clientChannelProperties Modifier to change the channel's configuration.
 * @throws IOException              if there's an issue using the network.
 * @throws ValueOutOfRangeException if the balance of wallet is lower than maxValue.
 */
public PaymentChannelClientConnection(InetSocketAddress server, int timeoutSeconds, Wallet wallet, ECKey myKey,
                                      Coin maxValue, String serverId,
                                      @Nullable KeyParameter userKeySetup, final ClientChannelProperties clientChannelProperties)
        throws IOException, ValueOutOfRangeException {
    // Glue the object which vends/ingests protobuf messages in order to manage state to the network object which
    // reads/writes them to the wire in length prefixed form.
    channelClient = new PaymentChannelClient(wallet, myKey, maxValue, Sha256Hash.of(serverId.getBytes()),
            userKeySetup, clientChannelProperties, new PaymentChannelClient.ClientConnection() {
        @Override
        public void sendToServer(Protos.TwoWayChannelMessage msg) {
            wireParser.write(msg);
        }

        @Override
        public void destroyConnection(PaymentChannelCloseException.CloseReason reason) {
            channelOpenFuture.setException(new PaymentChannelCloseException("Payment channel client requested that the connection be closed: " + reason, reason));
            wireParser.closeConnection();
        }

        @Override
        public boolean acceptExpireTime(long expireTime) {
            return expireTime <= (clientChannelProperties.timeWindow() + Utils.currentTimeSeconds() + 60);  // One extra minute to compensate for time skew and latency
        }

        @Override
        public void channelOpen(boolean wasInitiated) {
            wireParser.setSocketTimeout(0);
            // Inform the API user that we're done and ready to roll.
            channelOpenFuture.set(PaymentChannelClientConnection.this);
        }
    });

    // And glue back in the opposite direction - network to the channelClient.
    wireParser = new ProtobufConnection<Protos.TwoWayChannelMessage>(new ProtobufConnection.Listener<Protos.TwoWayChannelMessage>() {
        @Override
        public void messageReceived(ProtobufConnection<Protos.TwoWayChannelMessage> handler, Protos.TwoWayChannelMessage msg) {
            try {
                channelClient.receiveMessage(msg);
            } catch (InsufficientMoneyException e) {
                // We should only get this exception during INITIATE, so channelOpen wasn't called yet.
                channelOpenFuture.setException(e);
            }
        }

        @Override
        public void connectionOpen(ProtobufConnection<Protos.TwoWayChannelMessage> handler) {
            channelClient.connectionOpen();
        }

        @Override
        public void connectionClosed(ProtobufConnection<Protos.TwoWayChannelMessage> handler) {
            channelClient.connectionClosed();
            channelOpenFuture.setException(new PaymentChannelCloseException("The TCP socket died",
                    PaymentChannelCloseException.CloseReason.CONNECTION_CLOSED));
        }
    }, Protos.TwoWayChannelMessage.getDefaultInstance(), Short.MAX_VALUE, timeoutSeconds * 1000);

    // Initiate the outbound network connection. We don't need to keep this around. The wireParser object will handle
    // things from here on out.
    new NioClient(server, wireParser, timeoutSeconds * 1000);
}
 

@Test
public void autosaveDelayed() throws Exception {
    // Test that the wallet will save itself automatically when it changes, but not immediately and near-by
    // updates are coalesced together. This test is a bit racy, it assumes we can complete the unit test within
    // an auto-save cycle of 1 second.
    final File[] results = new File[2];
    final CountDownLatch latch = new CountDownLatch(3);
    File f = File.createTempFile("bitcoinj-unit-test", null);
    Sha256Hash hash1 = Sha256Hash.of(f);
    wallet.autosaveToFile(f, 1, TimeUnit.SECONDS,
            new WalletFiles.Listener() {
                @Override
                public void onBeforeAutoSave(File tempFile) {
                    results[0] = tempFile;
                }

                @Override
                public void onAfterAutoSave(File newlySavedFile) {
                    results[1] = newlySavedFile;
                    latch.countDown();
                }
            }
    );
    ECKey key = wallet.freshReceiveKey();
    Sha256Hash hash2 = Sha256Hash.of(f);
    assertFalse(hash1.equals(hash2));  // File has changed immediately despite the delay, as keys are important.
    assertNotNull(results[0]);
    assertEquals(f, results[1]);
    results[0] = results[1] = null;

    sendMoneyToWallet(BlockChain.NewBlockType.BEST_CHAIN);
    Sha256Hash hash3 = Sha256Hash.of(f);
    assertEquals(hash2, hash3);  // File has NOT changed yet. Just new blocks with no txns - delayed.
    assertNull(results[0]);
    assertNull(results[1]);

    sendMoneyToWallet(BlockChain.NewBlockType.BEST_CHAIN, valueOf(5, 0), key);
    Sha256Hash hash4 = Sha256Hash.of(f);
    assertFalse(hash3.equals(hash4));  // File HAS changed.
    results[0] = results[1] = null;

    // A block that contains some random tx we don't care about.
    sendMoneyToWallet(BlockChain.NewBlockType.BEST_CHAIN, Coin.COIN, OTHER_ADDRESS);
    assertEquals(hash4, Sha256Hash.of(f));  // File has NOT changed.
    assertNull(results[0]);
    assertNull(results[1]);

    // Wait for an auto-save to occur.
    latch.await();
    Sha256Hash hash5 = Sha256Hash.of(f);
    assertFalse(hash4.equals(hash5));  // File has now changed.
    assertNotNull(results[0]);
    assertEquals(f, results[1]);

    // Now we shutdown auto-saving and expect wallet changes to remain unsaved, even "important" changes.
    wallet.shutdownAutosaveAndWait();
    results[0] = results[1] = null;
    ECKey key2 = new ECKey();
    wallet.importKey(key2);
    assertEquals(hash5, Sha256Hash.of(f)); // File has NOT changed.
    sendMoneyToWallet(BlockChain.NewBlockType.BEST_CHAIN, valueOf(5, 0), key2);
    Thread.sleep(2000); // Wait longer than autosave delay. TODO Fix the racyness.
    assertEquals(hash5, Sha256Hash.of(f)); // File has still NOT changed.
    assertNull(results[0]);
    assertNull(results[1]);
}
 

/**
 * Attempts to open a new connection to and open a payment channel with the given host and port, blocking until the
 * connection is open.  The server is requested to keep the channel open for {@param timeWindow}
 * seconds. If the server proposes a longer time the channel will be closed.
 *
 * @param server The host/port pair where the server is listening.
 * @param timeoutSeconds The connection timeout and read timeout during initialization. This should be large enough
 *                       to accommodate ECDSA signature operations and network latency.
 * @param wallet The wallet which will be paid from, and where completed transactions will be committed.
 *               Can be encrypted if user key is supplied when needed. Must already have a
 *               {@link StoredPaymentChannelClientStates} object in its extensions set.
 * @param myKey A freshly generated keypair used for the multisig contract and refund output.
 * @param maxValue The maximum value this channel is allowed to request
 * @param serverId A unique ID which is used to attempt reopening of an existing channel.
 *                 This must be unique to the server, and, if your application is exposing payment channels to some
 *                 API, this should also probably encompass some caller UID to avoid applications opening channels
 *                 which were created by others.
 * @param userKeySetup Key derived from a user password, used to decrypt myKey, if it is encrypted, during setup.
 * @param clientChannelProperties Modifier to change the channel's configuration.
 *
 * @throws IOException if there's an issue using the network.
 * @throws ValueOutOfRangeException if the balance of wallet is lower than maxValue.
 */
public PaymentChannelClientConnection(InetSocketAddress server, int timeoutSeconds, Wallet wallet, ECKey myKey,
                                      Coin maxValue, String serverId,
                                      @Nullable KeyParameter userKeySetup, final ClientChannelProperties clientChannelProperties)
        throws IOException, ValueOutOfRangeException {
    // Glue the object which vends/ingests protobuf messages in order to manage state to the network object which
    // reads/writes them to the wire in length prefixed form.
    channelClient = new PaymentChannelClient(wallet, myKey, maxValue, Sha256Hash.of(serverId.getBytes()),
            userKeySetup, clientChannelProperties, new PaymentChannelClient.ClientConnection() {
        @Override
        public void sendToServer(Protos.TwoWayChannelMessage msg) {
            wireParser.write(msg);
        }

        @Override
        public void destroyConnection(PaymentChannelCloseException.CloseReason reason) {
            channelOpenFuture.setException(new PaymentChannelCloseException("Payment channel client requested that the connection be closed: " + reason, reason));
            wireParser.closeConnection();
        }

        @Override
        public boolean acceptExpireTime(long expireTime) {
            return expireTime <= (clientChannelProperties.timeWindow() + Utils.currentTimeSeconds() + 60);  // One extra minute to compensate for time skew and latency
        }

        @Override
        public void channelOpen(boolean wasInitiated) {
            wireParser.setSocketTimeout(0);
            // Inform the API user that we're done and ready to roll.
            channelOpenFuture.set(PaymentChannelClientConnection.this);
        }
    });

    // And glue back in the opposite direction - network to the channelClient.
    wireParser = new ProtobufConnection<Protos.TwoWayChannelMessage>(new ProtobufConnection.Listener<Protos.TwoWayChannelMessage>() {
        @Override
        public void messageReceived(ProtobufConnection<Protos.TwoWayChannelMessage> handler, Protos.TwoWayChannelMessage msg) {
            try {
                channelClient.receiveMessage(msg);
            } catch (InsufficientMoneyException e) {
                // We should only get this exception during INITIATE, so channelOpen wasn't called yet.
                channelOpenFuture.setException(e);
            }
        }

        @Override
        public void connectionOpen(ProtobufConnection<Protos.TwoWayChannelMessage> handler) {
            channelClient.connectionOpen();
        }

        @Override
        public void connectionClosed(ProtobufConnection<Protos.TwoWayChannelMessage> handler) {
            channelClient.connectionClosed();
            channelOpenFuture.setException(new PaymentChannelCloseException("The TCP socket died",
                    PaymentChannelCloseException.CloseReason.CONNECTION_CLOSED));
        }
    }, Protos.TwoWayChannelMessage.getDefaultInstance(), Short.MAX_VALUE, timeoutSeconds*1000);

    // Initiate the outbound network connection. We don't need to keep this around. The wireParser object will handle
    // things from here on out.
    new NioClient(server, wireParser, timeoutSeconds * 1000);
}
 

@Test
public void autosaveDelayed() throws Exception {
    // Test that the wallet will save itself automatically when it changes, but not immediately and near-by
    // updates are coalesced together. This test is a bit racy, it assumes we can complete the unit test within
    // an auto-save cycle of 1 second.
    final File[] results = new File[2];
    final CountDownLatch latch = new CountDownLatch(3);
    File f = File.createTempFile("bitcoinj-unit-test", null);
    Sha256Hash hash1 = Sha256Hash.of(f);
    wallet.autosaveToFile(f, 1, TimeUnit.SECONDS,
            new WalletFiles.Listener() {
                @Override
                public void onBeforeAutoSave(File tempFile) {
                    results[0] = tempFile;
                }

                @Override
                public void onAfterAutoSave(File newlySavedFile) {
                    results[1] = newlySavedFile;
                    latch.countDown();
                }
            }
    );
    ECKey key = wallet.freshReceiveKey();
    Sha256Hash hash2 = Sha256Hash.of(f);
    assertFalse(hash1.equals(hash2));  // File has changed immediately despite the delay, as keys are important.
    assertNotNull(results[0]);
    assertEquals(f, results[1]);
    results[0] = results[1] = null;

    sendMoneyToWallet(BlockChain.NewBlockType.BEST_CHAIN);
    Sha256Hash hash3 = Sha256Hash.of(f);
    assertEquals(hash2, hash3);  // File has NOT changed yet. Just new blocks with no txns - delayed.
    assertNull(results[0]);
    assertNull(results[1]);

    sendMoneyToWallet(BlockChain.NewBlockType.BEST_CHAIN, valueOf(5, 0), key);
    Sha256Hash hash4 = Sha256Hash.of(f);
    assertFalse(hash3.equals(hash4));  // File HAS changed.
    results[0] = results[1] = null;

    // A block that contains some random tx we don't care about.
    sendMoneyToWallet(BlockChain.NewBlockType.BEST_CHAIN, Coin.COIN, OTHER_ADDRESS);
    assertEquals(hash4, Sha256Hash.of(f));  // File has NOT changed.
    assertNull(results[0]);
    assertNull(results[1]);

    // Wait for an auto-save to occur.
    latch.await();
    Sha256Hash hash5 = Sha256Hash.of(f);
    assertFalse(hash4.equals(hash5));  // File has now changed.
    assertNotNull(results[0]);
    assertEquals(f, results[1]);

    // Now we shutdown auto-saving and expect wallet changes to remain unsaved, even "important" changes.
    wallet.shutdownAutosaveAndWait();
    results[0] = results[1] = null;
    ECKey key2 = new ECKey();
    wallet.importKey(key2);
    assertEquals(hash5, Sha256Hash.of(f)); // File has NOT changed.
    sendMoneyToWallet(BlockChain.NewBlockType.BEST_CHAIN, valueOf(5, 0), key2);
    Thread.sleep(2000); // Wait longer than autosave delay. TODO Fix the racyness.
    assertEquals(hash5, Sha256Hash.of(f)); // File has still NOT changed.
    assertNull(results[0]);
    assertNull(results[1]);
}
 

/**
 * Attempts to open a new connection to and open a payment channel with the given host and port, blocking until the
 * connection is open.  The server is requested to keep the channel open for {@param timeWindow}
 * seconds. If the server proposes a longer time the channel will be closed.
 *
 * @param server The host/port pair where the server is listening.
 * @param timeoutSeconds The connection timeout and read timeout during initialization. This should be large enough
 *                       to accommodate ECDSA signature operations and network latency.
 * @param wallet The wallet which will be paid from, and where completed transactions will be committed.
 *               Can be encrypted if user key is supplied when needed. Must already have a
 *               {@link StoredPaymentChannelClientStates} object in its extensions set.
 * @param myKey A freshly generated keypair used for the multisig contract and refund output.
 * @param maxValue The maximum value this channel is allowed to request
 * @param serverId A unique ID which is used to attempt reopening of an existing channel.
 *                 This must be unique to the server, and, if your application is exposing payment channels to some
 *                 API, this should also probably encompass some caller UID to avoid applications opening channels
 *                 which were created by others.
 * @param userKeySetup Key derived from a user password, used to decrypt myKey, if it is encrypted, during setup.
 * @param clientChannelProperties Modifier to change the channel's configuration.
 *
 * @throws IOException if there's an issue using the network.
 * @throws ValueOutOfRangeException if the balance of wallet is lower than maxValue.
 */
public PaymentChannelClientConnection(InetSocketAddress server, int timeoutSeconds, Wallet wallet, ECKey myKey,
                                      Coin maxValue, String serverId,
                                      @Nullable KeyParameter userKeySetup, final ClientChannelProperties clientChannelProperties)
        throws IOException, ValueOutOfRangeException {
    // Glue the object which vends/ingests protobuf messages in order to manage state to the network object which
    // reads/writes them to the wire in length prefixed form.
    channelClient = new PaymentChannelClient(wallet, myKey, maxValue, Sha256Hash.of(serverId.getBytes()),
            userKeySetup, clientChannelProperties, new PaymentChannelClient.ClientConnection() {
        @Override
        public void sendToServer(Protos.TwoWayChannelMessage msg) {
            wireParser.write(msg);
        }

        @Override
        public void destroyConnection(PaymentChannelCloseException.CloseReason reason) {
            channelOpenFuture.setException(new PaymentChannelCloseException("Payment channel client requested that the connection be closed: " + reason, reason));
            wireParser.closeConnection();
        }

        @Override
        public boolean acceptExpireTime(long expireTime) {
            return expireTime <= (clientChannelProperties.timeWindow() + Utils.currentTimeSeconds() + 60);  // One extra minute to compensate for time skew and latency
        }

        @Override
        public void channelOpen(boolean wasInitiated) {
            wireParser.setSocketTimeout(0);
            // Inform the API user that we're done and ready to roll.
            channelOpenFuture.set(PaymentChannelClientConnection.this);
        }
    });

    // And glue back in the opposite direction - network to the channelClient.
    wireParser = new ProtobufConnection<Protos.TwoWayChannelMessage>(new ProtobufConnection.Listener<Protos.TwoWayChannelMessage>() {
        @Override
        public void messageReceived(ProtobufConnection<Protos.TwoWayChannelMessage> handler, Protos.TwoWayChannelMessage msg) {
            try {
                channelClient.receiveMessage(msg);
            } catch (InsufficientMoneyException e) {
                // We should only get this exception during INITIATE, so channelOpen wasn't called yet.
                channelOpenFuture.setException(e);
            }
        }

        @Override
        public void connectionOpen(ProtobufConnection<Protos.TwoWayChannelMessage> handler) {
            channelClient.connectionOpen();
        }

        @Override
        public void connectionClosed(ProtobufConnection<Protos.TwoWayChannelMessage> handler) {
            channelClient.connectionClosed();
            channelOpenFuture.setException(new PaymentChannelCloseException("The TCP socket died",
                    PaymentChannelCloseException.CloseReason.CONNECTION_CLOSED));
        }
    }, Protos.TwoWayChannelMessage.getDefaultInstance(), Short.MAX_VALUE, timeoutSeconds*1000);

    // Initiate the outbound network connection. We don't need to keep this around. The wireParser object will handle
    // things from here on out.
    new NioClient(server, wireParser, timeoutSeconds * 1000);
}
 

@Test
public void autosaveDelayed() throws Exception {
    // Test that the wallet will save itself automatically when it changes, but not immediately and near-by
    // updates are coalesced together. This test is a bit racy, it assumes we can complete the unit test within
    // an auto-save cycle of 1 second.
    final File[] results = new File[2];
    final CountDownLatch latch = new CountDownLatch(3);
    File f = File.createTempFile("bitcoinj-unit-test", null);
    Sha256Hash hash1 = Sha256Hash.of(f);
    wallet.autosaveToFile(f, 1, TimeUnit.SECONDS,
            new WalletFiles.Listener() {
                @Override
                public void onBeforeAutoSave(File tempFile) {
                    results[0] = tempFile;
                }

                @Override
                public void onAfterAutoSave(File newlySavedFile) {
                    results[1] = newlySavedFile;
                    latch.countDown();
                }
            }
    );
    ECKey key = wallet.freshReceiveKey();
    Sha256Hash hash2 = Sha256Hash.of(f);
    assertFalse(hash1.equals(hash2));  // File has changed immediately despite the delay, as keys are important.
    assertNotNull(results[0]);
    assertEquals(f, results[1]);
    results[0] = results[1] = null;

    sendMoneyToWallet(BlockChain.NewBlockType.BEST_CHAIN);
    Sha256Hash hash3 = Sha256Hash.of(f);
    assertEquals(hash2, hash3);  // File has NOT changed yet. Just new blocks with no txns - delayed.
    assertNull(results[0]);
    assertNull(results[1]);

    sendMoneyToWallet(BlockChain.NewBlockType.BEST_CHAIN, valueOf(5, 0), key);
    Sha256Hash hash4 = Sha256Hash.of(f);
    assertFalse(hash3.equals(hash4));  // File HAS changed.
    results[0] = results[1] = null;

    // A block that contains some random tx we don't care about.
    sendMoneyToWallet(BlockChain.NewBlockType.BEST_CHAIN, Coin.COIN, OTHER_ADDRESS);
    assertEquals(hash4, Sha256Hash.of(f));  // File has NOT changed.
    assertNull(results[0]);
    assertNull(results[1]);

    // Wait for an auto-save to occur.
    latch.await();
    Sha256Hash hash5 = Sha256Hash.of(f);
    assertFalse(hash4.equals(hash5));  // File has now changed.
    assertNotNull(results[0]);
    assertEquals(f, results[1]);

    // Now we shutdown auto-saving and expect wallet changes to remain unsaved, even "important" changes.
    wallet.shutdownAutosaveAndWait();
    results[0] = results[1] = null;
    ECKey key2 = new ECKey();
    wallet.importKey(key2);
    assertEquals(hash5, Sha256Hash.of(f)); // File has NOT changed.
    sendMoneyToWallet(BlockChain.NewBlockType.BEST_CHAIN, valueOf(5, 0), key2);
    Thread.sleep(2000); // Wait longer than autosave delay. TODO Fix the racyness.
    assertEquals(hash5, Sha256Hash.of(f)); // File has still NOT changed.
    assertNull(results[0]);
    assertNull(results[1]);
}