diff --git a/BUILD b/BUILD
index 8eb7d2a..81ab40d 100644
--- a/BUILD
+++ b/BUILD
@@ -41,6 +41,5 @@
     exports = PLUGIN_DEPS + PLUGIN_TEST_DEPS + [
         ":lfs__plugin",
         "@jgit-lfs//jar",
-        "@joda-time//jar",
     ],
 )
diff --git a/external_plugin_deps.bzl b/external_plugin_deps.bzl
index e814f4b..798575c 100644
--- a/external_plugin_deps.bzl
+++ b/external_plugin_deps.bzl
@@ -36,9 +36,3 @@
             "plugin.properties",
         ],
     )
-
-    maven_jar(
-        name = "joda-time",
-        artifact = "joda-time:joda-time:2.9.9",
-        sha1 = "f7b520c458572890807d143670c9b24f4de90897",
-    )
diff --git a/src/main/java/com/googlesource/gerrit/plugins/lfs/InitLfs.java b/src/main/java/com/googlesource/gerrit/plugins/lfs/InitLfs.java
index 89e6238..f44c8d8 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/lfs/InitLfs.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/lfs/InitLfs.java
@@ -36,7 +36,4 @@
   public void run() throws Exception {
     lfs.set(PLUGIN_KEY, name);
   }
-
-  @Override
-  public void postRun() throws Exception {}
 }
diff --git a/src/main/java/com/googlesource/gerrit/plugins/lfs/LfsDateTime.java b/src/main/java/com/googlesource/gerrit/plugins/lfs/LfsDateTime.java
index 4a1936c..1a4c689 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/lfs/LfsDateTime.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/lfs/LfsDateTime.java
@@ -20,6 +20,8 @@
 import java.util.Locale;
 
 public class LfsDateTime {
+  private LfsDateTime() {}
+
   private static final DateTimeFormatter FORMAT =
       DateTimeFormatter.ofPattern("yyyy-MM-dd'T'HH:mm:ss.SSSZZZZZ")
           .withZone(ZoneOffset.UTC)
diff --git a/src/main/java/com/googlesource/gerrit/plugins/lfs/LfsGson.java b/src/main/java/com/googlesource/gerrit/plugins/lfs/LfsGson.java
index 66398fe..f2af66e 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/lfs/LfsGson.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/lfs/LfsGson.java
@@ -17,8 +17,6 @@
 import com.google.gson.FieldNamingPolicy;
 import com.google.gson.Gson;
 import com.google.gson.GsonBuilder;
-import com.google.gson.JsonIOException;
-import com.google.gson.JsonSyntaxException;
 import com.google.inject.Singleton;
 import java.io.Reader;
 
@@ -34,7 +32,7 @@
             .create();
   }
 
-  public void toJson(Object src, Appendable writer) throws JsonIOException {
+  public void toJson(Object src, Appendable writer) {
     gson.toJson(src, writer);
   }
 
@@ -42,8 +40,7 @@
     return gson.toJson(src);
   }
 
-  public <T> T fromJson(Reader json, Class<T> classOfT)
-      throws JsonSyntaxException, JsonIOException {
+  public <T> T fromJson(Reader json, Class<T> classOfT) {
     return gson.fromJson(json, classOfT);
   }
 }
diff --git a/src/main/java/com/googlesource/gerrit/plugins/lfs/auth/LfsAuthUserProvider.java b/src/main/java/com/googlesource/gerrit/plugins/lfs/auth/LfsAuthUserProvider.java
index fcd4736..cc19dd3 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/lfs/auth/LfsAuthUserProvider.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/lfs/auth/LfsAuthUserProvider.java
@@ -14,6 +14,7 @@
 
 package com.googlesource.gerrit.plugins.lfs.auth;
 
+import static com.google.common.base.MoreObjects.firstNonNull;
 import static com.googlesource.gerrit.plugins.lfs.auth.LfsSshRequestAuthorizer.SSH_AUTH_PREFIX;
 
 import com.google.common.base.Strings;
@@ -30,7 +31,7 @@
 @Singleton
 public class LfsAuthUserProvider {
   private final Provider<AnonymousUser> anonymous;
-  private final Provider<CurrentUser> user;
+  private final Provider<CurrentUser> currentUser;
   private final LfsSshRequestAuthorizer sshAuth;
   private final AccountCache accounts;
   private final IdentifiedUser.GenericFactory userFactory;
@@ -38,12 +39,12 @@
   @Inject
   LfsAuthUserProvider(
       Provider<AnonymousUser> anonymous,
-      Provider<CurrentUser> user,
+      Provider<CurrentUser> currentUser,
       LfsSshRequestAuthorizer sshAuth,
       AccountCache accounts,
       IdentifiedUser.GenericFactory userFactory) {
     this.anonymous = anonymous;
-    this.user = user;
+    this.currentUser = currentUser;
     this.sshAuth = sshAuth;
     this.accounts = accounts;
     this.userFactory = userFactory;
@@ -61,7 +62,6 @@
         }
       }
     }
-    CurrentUser currentUser = user.get();
-    return currentUser != null ? currentUser : anonymous.get();
+    return firstNonNull(currentUser.get(), anonymous.get());
   }
 }
diff --git a/src/main/java/com/googlesource/gerrit/plugins/lfs/auth/LfsSshAuth.java b/src/main/java/com/googlesource/gerrit/plugins/lfs/auth/LfsSshAuth.java
index 9fd57b9..3dd7a86 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/lfs/auth/LfsSshAuth.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/lfs/auth/LfsSshAuth.java
@@ -44,7 +44,7 @@
   }
 
   @Override
-  public String authenticate(CurrentUser user, List<String> args) throws UnloggedFailure, Failure {
+  public String authenticate(CurrentUser user, List<String> args) throws Failure {
     if (args.size() != 2) {
       throw new UnloggedFailure(1, "Unexpected number of arguments");
     }
diff --git a/src/main/java/com/googlesource/gerrit/plugins/lfs/locks/LfsLocksHandler.java b/src/main/java/com/googlesource/gerrit/plugins/lfs/locks/LfsLocksHandler.java
index 8ba263e..932a92d 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/lfs/locks/LfsLocksHandler.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/lfs/locks/LfsLocksHandler.java
@@ -14,6 +14,8 @@
 
 package com.googlesource.gerrit.plugins.lfs.locks;
 
+import static java.util.stream.Collectors.groupingBy;
+
 import com.google.common.cache.CacheLoader;
 import com.google.common.cache.LoadingCache;
 import com.google.common.collect.ImmutableList;
@@ -29,7 +31,6 @@
 import java.util.List;
 import java.util.Map;
 import java.util.Optional;
-import java.util.stream.Collectors;
 import org.eclipse.jgit.lfs.errors.LfsException;
 
 @Singleton
@@ -66,14 +67,10 @@
     };
   }
 
-  private final PathToLockId toLockId;
   private final LoadingCache<Project.NameKey, LfsProjectLocks> projectLocks;
 
   @Inject
-  LfsLocksHandler(
-      PathToLockId toLockId,
-      @Named(CACHE_NAME) LoadingCache<Project.NameKey, LfsProjectLocks> projectLocks) {
-    this.toLockId = toLockId;
+  LfsLocksHandler(@Named(CACHE_NAME) LoadingCache<Project.NameKey, LfsProjectLocks> projectLocks) {
     this.projectLocks = projectLocks;
   }
 
@@ -99,10 +96,9 @@
     }
 
     LfsLock lock = hasLock.get();
-    if (lock.owner.name.equals(user.getUserName().get())) {
-      locks.deleteLock(lock);
-      return new LfsLockResponse(lock);
-    } else if (input.force) {
+    Optional<String> username = user.getUserName();
+    if ((username.isPresent() && lock.owner.name.equals(username.get()))
+        || Boolean.TRUE.equals(input.force)) {
       locks.deleteLock(lock);
       return new LfsLockResponse(lock);
     }
@@ -116,18 +112,13 @@
     LfsProjectLocks locks = projectLocks.getUnchecked(project);
     Map<Boolean, List<LfsLock>> groupByOurs =
         locks.getLocks().stream()
-            .collect(
-                Collectors.groupingBy(
-                    (in) -> {
-                      return in.owner.name.equals(user.getUserName().get());
-                    }));
+            .collect(groupingBy(in -> in.owner.name.equals(user.getUserName().get())));
     return new LfsVerifyLocksResponse(groupByOurs.get(true), groupByOurs.get(false), null);
   }
 
   LfsGetLocksResponse listLocksByPath(Project.NameKey project, String path) {
     log.atFine().log("Get lock for %s path in %s project", path, project);
-    String lockId = toLockId.apply(path);
-    return listLocksById(project, lockId);
+    return listLocksById(project, PathToLockId.CONVERTER.convert(path));
   }
 
   LfsGetLocksResponse listLocksById(Project.NameKey project, String id) {
diff --git a/src/main/java/com/googlesource/gerrit/plugins/lfs/locks/LfsProjectLocks.java b/src/main/java/com/googlesource/gerrit/plugins/lfs/locks/LfsProjectLocks.java
index b02e089..8c0345c 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/lfs/locks/LfsProjectLocks.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/lfs/locks/LfsProjectLocks.java
@@ -43,19 +43,13 @@
 
   private static final FluentLogger log = FluentLogger.forEnclosingClass();
   private final LfsGson gson;
-  private final PathToLockId toLockId;
   private final String project;
   private final Path locksPath;
   private final Cache<String, LfsLock> locks;
 
   @Inject
-  LfsProjectLocks(
-      LfsGson gson,
-      PathToLockId toLockId,
-      LfsLocksPathProvider locksPath,
-      @Assisted Project.NameKey project) {
+  LfsProjectLocks(LfsGson gson, LfsLocksPathProvider locksPath, @Assisted Project.NameKey project) {
     this.gson = gson;
-    this.toLockId = toLockId;
     this.project = project.get();
     this.locksPath = Paths.get(locksPath.get(), this.project);
     this.locks = CacheBuilder.newBuilder().build();
@@ -94,7 +88,7 @@
 
   LfsLock createLock(CurrentUser user, LfsCreateLockInput input) throws LfsException {
     log.atFine().log("Create lock for %s in project %s", input.path, project);
-    String lockId = toLockId.apply(input.path);
+    String lockId = PathToLockId.CONVERTER.convert(input.path);
     LfsLock lock = locks.getIfPresent(lockId);
     if (lock != null) {
       throw new LfsLockExistsException(lock);
diff --git a/src/main/java/com/googlesource/gerrit/plugins/lfs/locks/PathToLockId.java b/src/main/java/com/googlesource/gerrit/plugins/lfs/locks/PathToLockId.java
index d90ebb8..4449469 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/lfs/locks/PathToLockId.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/lfs/locks/PathToLockId.java
@@ -14,16 +14,22 @@
 
 package com.googlesource.gerrit.plugins.lfs.locks;
 
-import com.google.common.base.Function;
-import com.google.common.hash.HashCode;
+import static java.nio.charset.StandardCharsets.UTF_8;
+
 import com.google.common.hash.Hashing;
 import com.google.common.io.BaseEncoding;
-import java.nio.charset.StandardCharsets;
 
-public class PathToLockId implements Function<String, String> {
-  @Override
-  public String apply(String path) {
-    HashCode hash = Hashing.sha256().hashString(path, StandardCharsets.UTF_8);
-    return BaseEncoding.base16().lowerCase().encode(hash.asBytes());
+public class PathToLockId {
+  private PathToLockId() {}
+
+  @FunctionalInterface
+  public interface PathToLockIdInterface {
+    String convert(String path);
   }
+
+  static final PathToLockIdInterface CONVERTER =
+      path ->
+          BaseEncoding.base16()
+              .lowerCase()
+              .encode(Hashing.sha256().hashString(path, UTF_8).asBytes());
 }
diff --git a/src/test/java/com/googlesource/gerrit/plugins/lfs/LfsDateTimeTest.java b/src/test/java/com/googlesource/gerrit/plugins/lfs/LfsDateTimeTest.java
deleted file mode 100644
index e2852c5..0000000
--- a/src/test/java/com/googlesource/gerrit/plugins/lfs/LfsDateTimeTest.java
+++ /dev/null
@@ -1,32 +0,0 @@
-// Copyright (C) 2017 The Android Open Source Project
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package com.googlesource.gerrit.plugins.lfs;
-
-import static com.google.common.truth.Truth.assertThat;
-
-import java.time.Instant;
-import org.joda.time.DateTime;
-import org.joda.time.format.ISODateTimeFormat;
-import org.junit.Test;
-
-public class LfsDateTimeTest {
-  @Test
-  public void format() throws Exception {
-    DateTime now = DateTime.now();
-    String jodaFormat = ISODateTimeFormat.dateTime().withZoneUTC().print(now);
-    String javaFormat = LfsDateTime.format(Instant.ofEpochMilli(now.getMillis()));
-    assertThat(javaFormat).isEqualTo(jodaFormat);
-  }
-}
diff --git a/src/test/java/com/googlesource/gerrit/plugins/lfs/auth/LfsAuthTokenTest.java b/src/test/java/com/googlesource/gerrit/plugins/lfs/auth/LfsAuthTokenTest.java
index bdf7c21..f527aab 100644
--- a/src/test/java/com/googlesource/gerrit/plugins/lfs/auth/LfsAuthTokenTest.java
+++ b/src/test/java/com/googlesource/gerrit/plugins/lfs/auth/LfsAuthTokenTest.java
@@ -15,6 +15,7 @@
 package com.googlesource.gerrit.plugins.lfs.auth;
 
 import static com.google.common.truth.Truth.assertThat;
+import static com.google.common.truth.Truth8.assertThat;
 
 import com.googlesource.gerrit.plugins.lfs.LfsDateTime;
 import java.time.Instant;
@@ -33,7 +34,7 @@
     String serialized = processor.serialize(token);
     assertThat(serialized).isNotEmpty();
     Optional<TestToken> deserialized = processor.deserialize(serialized);
-    assertThat(deserialized.isPresent()).isTrue();
+    assertThat(deserialized).isPresent();
     assertThat(token.issued).isEqualTo(deserialized.get().issued);
   }
 
diff --git a/src/test/java/com/googlesource/gerrit/plugins/lfs/auth/LfsCipherTest.java b/src/test/java/com/googlesource/gerrit/plugins/lfs/auth/LfsCipherTest.java
index 08d8dc8..3072767 100644
--- a/src/test/java/com/googlesource/gerrit/plugins/lfs/auth/LfsCipherTest.java
+++ b/src/test/java/com/googlesource/gerrit/plugins/lfs/auth/LfsCipherTest.java
@@ -15,44 +15,44 @@
 package com.googlesource.gerrit.plugins.lfs.auth;
 
 import static com.google.common.truth.Truth.assertThat;
+import static com.google.common.truth.Truth8.assertThat;
 
 import java.util.Optional;
 import org.junit.Test;
 
 public class LfsCipherTest {
+  private static final String PLAIN_TEXT = "plain text";
+
   private final LfsCipher cipher = new LfsCipher();
 
   @Test
   public void testCipherTextIsDifferentThanInput() throws Exception {
-    String plain = "plain text";
-    String encrypted = cipher.encrypt(plain);
+    String encrypted = cipher.encrypt(PLAIN_TEXT);
     assertThat(encrypted).isNotEmpty();
-    assertThat(encrypted).isNotEqualTo(plain);
+    assertThat(encrypted).isNotEqualTo(PLAIN_TEXT);
   }
 
   @Test
   public void testVerifyDecodeAgainstEncodedInput() throws Exception {
-    String plain = "plain text";
-    String encrypted = cipher.encrypt(plain);
+    String encrypted = cipher.encrypt(PLAIN_TEXT);
     Optional<String> decrypted = cipher.decrypt(encrypted);
-    assertThat(decrypted.isPresent()).isTrue();
-    assertThat(decrypted.get()).isEqualTo(plain);
+    assertThat(decrypted).isPresent();
+    assertThat(decrypted.get()).isEqualTo(PLAIN_TEXT);
   }
 
   @Test
   public void testVerifyDecodeAgainstInvalidInput() throws Exception {
-    String plain = "plain text";
-    String encrypted = cipher.encrypt(plain);
+    String encrypted = cipher.encrypt(PLAIN_TEXT);
     // there is a chance that two first chars in token are the same
     // in such case re-generate the token
     while (encrypted.charAt(0) == encrypted.charAt(1)) {
-      encrypted = cipher.encrypt(plain);
+      encrypted = cipher.encrypt(PLAIN_TEXT);
     }
 
     Optional<String> decrypted =
         cipher.decrypt(
             encrypted.substring(1, 2) + encrypted.substring(0, 1) + encrypted.substring(2));
-    assertThat(decrypted.isPresent()).isTrue();
-    assertThat(decrypted.get()).isNotEqualTo(plain);
+    assertThat(decrypted).isPresent();
+    assertThat(decrypted.get()).isNotEqualTo(PLAIN_TEXT);
   }
 }