diff --git a/src/main/java/com/googlesource/gerrit/plugins/hooks/AgreementSignup.java b/src/main/java/com/googlesource/gerrit/plugins/hooks/AgreementSignup.java
index 3953bf6..0eb9b6f 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/hooks/AgreementSignup.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/hooks/AgreementSignup.java
@@ -21,7 +21,7 @@
 
 @Singleton
 class AgreementSignup implements AgreementSignupListener {
-  private final AsynchronousHook hook;
+  private final Hook hook;
   private final HookFactory hookFactory;
 
   @Inject
@@ -40,7 +40,7 @@
       args.add("--user-id", submitter._accountId);
       args.add("--cla-name", event.getAgreementName());
 
-      hook.submit(args);
+      hook.execute(args);
     }
   }
 }
diff --git a/src/main/java/com/googlesource/gerrit/plugins/hooks/AsynchronousHook.java b/src/main/java/com/googlesource/gerrit/plugins/hooks/AsynchronousHook.java
index c581642..4e74ece 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/hooks/AsynchronousHook.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/hooks/AsynchronousHook.java
@@ -16,7 +16,7 @@
 
 import java.nio.file.Path;
 
-public class AsynchronousHook extends Hook {
+class AsynchronousHook extends Hook {
   private final HookQueue queue;
 
   AsynchronousHook(HookQueue queue, Path path) {
@@ -24,11 +24,15 @@
     this.queue = queue;
   }
 
-  void submit(HookArgs args) {
+  @Override
+  HookResult execute(HookArgs args) {
     queue.submit(path, args);
+    return null;
   }
 
-  void submit(String projectName, HookArgs args) {
+  @Override
+  HookResult execute(String projectName, HookArgs args) {
     queue.submit(projectName, path, args);
+    return null;
   }
 }
diff --git a/src/main/java/com/googlesource/gerrit/plugins/hooks/ChangeAbandoned.java b/src/main/java/com/googlesource/gerrit/plugins/hooks/ChangeAbandoned.java
index 19e6753..20ace66 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/hooks/ChangeAbandoned.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/hooks/ChangeAbandoned.java
@@ -21,7 +21,7 @@
 
 @Singleton
 class ChangeAbandoned implements ChangeAbandonedListener {
-  private final AsynchronousHook hook;
+  private final Hook hook;
   private final HookFactory hookFactory;
 
   @Inject
@@ -45,6 +45,6 @@
     args.add("--commit", c.currentRevision);
     args.add("--reason", event.getReason());
 
-    hook.submit(c.project, args);
+    hook.execute(c.project, args);
   }
 }
diff --git a/src/main/java/com/googlesource/gerrit/plugins/hooks/ChangeMerged.java b/src/main/java/com/googlesource/gerrit/plugins/hooks/ChangeMerged.java
index 6e28143..6ef03e0 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/hooks/ChangeMerged.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/hooks/ChangeMerged.java
@@ -21,7 +21,7 @@
 
 @Singleton
 class ChangeMerged implements ChangeMergedListener {
-  private final AsynchronousHook hook;
+  private final Hook hook;
   private final HookFactory hookFactory;
 
   @Inject
@@ -45,6 +45,6 @@
     args.add("--commit", c.currentRevision);
     args.add("--newrev", event.getNewRevisionId());
 
-    hook.submit(c.project, args);
+    hook.execute(c.project, args);
   }
 }
diff --git a/src/main/java/com/googlesource/gerrit/plugins/hooks/ChangeRestored.java b/src/main/java/com/googlesource/gerrit/plugins/hooks/ChangeRestored.java
index af0f9a8..27b1c07 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/hooks/ChangeRestored.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/hooks/ChangeRestored.java
@@ -21,7 +21,7 @@
 
 @Singleton
 class ChangeRestored implements ChangeRestoredListener {
-  private final AsynchronousHook hook;
+  private final Hook hook;
   private final HookFactory hookFactory;
 
   @Inject
@@ -45,6 +45,6 @@
     args.add("--commit", c.currentRevision);
     args.add("--reason", event.getReason());
 
-    hook.submit(c.project, args);
+    hook.execute(c.project, args);
   }
 }
diff --git a/src/main/java/com/googlesource/gerrit/plugins/hooks/CommentAdded.java b/src/main/java/com/googlesource/gerrit/plugins/hooks/CommentAdded.java
index cea65d1..531f0ce 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/hooks/CommentAdded.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/hooks/CommentAdded.java
@@ -21,7 +21,7 @@
 
 @Singleton
 class CommentAdded implements CommentAddedListener {
-  private final AsynchronousHook hook;
+  private final Hook hook;
   private final HookFactory hookFactory;
 
   @Inject
@@ -47,6 +47,6 @@
     args.add("--comment", event.getComment());
     args.addApprovals(event.getApprovals(), event.getOldApprovals());
 
-    hook.submit(c.project, args);
+    hook.execute(c.project, args);
   }
 }
diff --git a/src/main/java/com/googlesource/gerrit/plugins/hooks/CommitReceived.java b/src/main/java/com/googlesource/gerrit/plugins/hooks/CommitReceived.java
index ba4cec6..73b5ff5 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/hooks/CommitReceived.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/hooks/CommitReceived.java
@@ -25,7 +25,7 @@
 import org.eclipse.jgit.lib.ObjectId;
 
 public class CommitReceived implements CommitValidationListener {
-  private final SynchronousHook hook;
+  private final Hook hook;
   private final HookFactory hookFactory;
 
   @Inject
@@ -54,7 +54,7 @@
     args.add("--newrev", receiveEvent.commit.name());
     args.add("--cmdref", commandRef);
 
-    HookResult result = hook.run(projectName, args);
+    HookResult result = hook.execute(projectName, args);
     if (result != null) {
       String output = result.toString();
       if (result.getExitValue() != 0) {
diff --git a/src/main/java/com/googlesource/gerrit/plugins/hooks/DraftPublished.java b/src/main/java/com/googlesource/gerrit/plugins/hooks/DraftPublished.java
index 7ae68f2..8fe8cde 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/hooks/DraftPublished.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/hooks/DraftPublished.java
@@ -21,7 +21,7 @@
 
 @Singleton
 class DraftPublished implements DraftPublishedListener {
-  private final AsynchronousHook hook;
+  private final Hook hook;
   private final HookFactory hookFactory;
 
   @Inject
@@ -45,6 +45,6 @@
     args.add("--commit", event.getRevision().commit.commit);
     args.add("--patchset", event.getRevision()._number);
 
-    hook.submit(c.project, args);
+    hook.execute(c.project, args);
   }
 }
diff --git a/src/main/java/com/googlesource/gerrit/plugins/hooks/GitReferenceUpdated.java b/src/main/java/com/googlesource/gerrit/plugins/hooks/GitReferenceUpdated.java
index cf1a10d..07fff1e 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/hooks/GitReferenceUpdated.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/hooks/GitReferenceUpdated.java
@@ -20,7 +20,7 @@
 
 @Singleton
 class GitReferenceUpdated implements GitReferenceUpdatedListener {
-  private final AsynchronousHook hook;
+  private final Hook hook;
   private final HookFactory hookFactory;
 
   @Inject
@@ -39,6 +39,6 @@
     args.add("--project", event.getProjectName());
     args.add("--submitter", event.getUpdater());
 
-    hook.submit(event.getProjectName(), args);
+    hook.execute(event.getProjectName(), args);
   }
 }
diff --git a/src/main/java/com/googlesource/gerrit/plugins/hooks/HashtagsEdited.java b/src/main/java/com/googlesource/gerrit/plugins/hooks/HashtagsEdited.java
index 9bb40c1..7735b38 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/hooks/HashtagsEdited.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/hooks/HashtagsEdited.java
@@ -22,7 +22,7 @@
 
 @Singleton
 class HashtagsEdited implements HashtagsEditedListener {
-  private final AsynchronousHook hook;
+  private final Hook hook;
   private final HookFactory hookFactory;
 
   @Inject
@@ -45,7 +45,7 @@
     add(args, "--added", event.getAddedHashtags());
     add(args, "--removed", event.getRemovedHashtags());
 
-    hook.submit(c.project, args);
+    hook.execute(c.project, args);
   }
 
   private void add(HookArgs args, String name, Collection<String> hashtags) {
diff --git a/src/main/java/com/googlesource/gerrit/plugins/hooks/Hook.java b/src/main/java/com/googlesource/gerrit/plugins/hooks/Hook.java
index 87fb4f4..fc84b9e 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/hooks/Hook.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/hooks/Hook.java
@@ -14,12 +14,17 @@
 
 package com.googlesource.gerrit.plugins.hooks;
 
+import com.google.gerrit.common.Nullable;
 import java.nio.file.Path;
 
-public class Hook {
+abstract class Hook {
   protected final Path path;
 
   Hook(Path path) {
     this.path = path;
   }
+
+  abstract @Nullable HookResult execute(HookArgs args);
+
+  abstract @Nullable HookResult execute(String projectName, HookArgs args);
 }
diff --git a/src/main/java/com/googlesource/gerrit/plugins/hooks/HookFactory.java b/src/main/java/com/googlesource/gerrit/plugins/hooks/HookFactory.java
index ab4a615..c3ca6e1 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/hooks/HookFactory.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/hooks/HookFactory.java
@@ -57,11 +57,11 @@
     return hooksPath.resolve(firstNonNull(v, defaultName));
   }
 
-  public AsynchronousHook createAsync(String configName, String defaultName) {
+  public Hook createAsync(String configName, String defaultName) {
     return new AsynchronousHook(queue, getHookPath(configName, defaultName));
   }
 
-  public SynchronousHook createSync(String configName, String defaultName) {
+  public Hook createSync(String configName, String defaultName) {
     return new SynchronousHook(syncHookExecutor, getHookPath(configName, defaultName));
   }
 
diff --git a/src/main/java/com/googlesource/gerrit/plugins/hooks/NewProjectCreated.java b/src/main/java/com/googlesource/gerrit/plugins/hooks/NewProjectCreated.java
index 5ff73f7..0cf0e88 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/hooks/NewProjectCreated.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/hooks/NewProjectCreated.java
@@ -20,7 +20,7 @@
 
 @Singleton
 class NewProjectCreated implements NewProjectCreatedListener {
-  private final AsynchronousHook hook;
+  private final Hook hook;
   private final HookFactory hookFactory;
 
   @Inject
@@ -34,6 +34,6 @@
     HookArgs args = hookFactory.createArgs();
     args.add("--project", event.getProjectName());
     args.add("--head", event.getHeadName());
-    hook.submit(event.getProjectName(), args);
+    hook.execute(event.getProjectName(), args);
   }
 }
diff --git a/src/main/java/com/googlesource/gerrit/plugins/hooks/RefUpdate.java b/src/main/java/com/googlesource/gerrit/plugins/hooks/RefUpdate.java
index 7618d97..d6cba66 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/hooks/RefUpdate.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/hooks/RefUpdate.java
@@ -24,7 +24,7 @@
 import java.util.List;
 
 public class RefUpdate implements RefOperationValidationListener {
-  private final SynchronousHook hook;
+  private final Hook hook;
   private final HookFactory hookFactory;
 
   @Inject
@@ -46,7 +46,7 @@
     args.add("--newrev", refEvent.command.getNewId().getName());
     args.add("--refname", refEvent.command.getRefName());
 
-    HookResult result = hook.run(projectName, args);
+    HookResult result = hook.execute(projectName, args);
     if (result != null) {
       String output = result.toString();
       if (result.getExitValue() != 0) {
diff --git a/src/main/java/com/googlesource/gerrit/plugins/hooks/ReviewerAdded.java b/src/main/java/com/googlesource/gerrit/plugins/hooks/ReviewerAdded.java
index fca527d..9929255 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/hooks/ReviewerAdded.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/hooks/ReviewerAdded.java
@@ -22,7 +22,7 @@
 
 @Singleton
 class ReviewerAdded implements ReviewerAddedListener {
-  private final AsynchronousHook hook;
+  private final Hook hook;
   private final HookFactory hookFactory;
 
   @Inject
@@ -44,7 +44,7 @@
       args.add("--branch", c.branch);
       args.add("--reviewer", reviewer);
 
-      hook.submit(c.project, args);
+      hook.execute(c.project, args);
     }
   }
 }
diff --git a/src/main/java/com/googlesource/gerrit/plugins/hooks/ReviewerDeleted.java b/src/main/java/com/googlesource/gerrit/plugins/hooks/ReviewerDeleted.java
index e23677d..0cf6ce7 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/hooks/ReviewerDeleted.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/hooks/ReviewerDeleted.java
@@ -21,7 +21,7 @@
 
 @Singleton
 class ReviewerDeleted implements ReviewerDeletedListener {
-  private final AsynchronousHook hook;
+  private final Hook hook;
   private final HookFactory hookFactory;
 
   @Inject
@@ -43,6 +43,6 @@
     args.add("--reviewer", event.getReviewer());
     args.addApprovals(event.getNewApprovals(), event.getOldApprovals());
 
-    hook.submit(c.project, args);
+    hook.execute(c.project, args);
   }
 }
diff --git a/src/main/java/com/googlesource/gerrit/plugins/hooks/RevisionCreated.java b/src/main/java/com/googlesource/gerrit/plugins/hooks/RevisionCreated.java
index cd4a9d1..ebf5a7b 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/hooks/RevisionCreated.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/hooks/RevisionCreated.java
@@ -21,7 +21,7 @@
 
 @Singleton
 public class RevisionCreated implements RevisionCreatedListener {
-  private final AsynchronousHook hook;
+  private final Hook hook;
   private final HookFactory hookFactory;
 
   @Inject
@@ -47,6 +47,6 @@
     args.add("--commit", event.getRevision().commit.commit);
     args.add("--patchset", event.getRevision()._number);
 
-    hook.submit(c.project, args);
+    hook.execute(c.project, args);
   }
 }
diff --git a/src/main/java/com/googlesource/gerrit/plugins/hooks/SynchronousHook.java b/src/main/java/com/googlesource/gerrit/plugins/hooks/SynchronousHook.java
index 03cbc40..d4dfaf8 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/hooks/SynchronousHook.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/hooks/SynchronousHook.java
@@ -24,11 +24,13 @@
     this.executor = executor;
   }
 
-  HookResult run(HookArgs args) {
+  @Override
+  HookResult execute(HookArgs args) {
     return executor.submit(path, args);
   }
 
-  HookResult run(String projectName, HookArgs args) {
+  @Override
+  HookResult execute(String projectName, HookArgs args) {
     return executor.submit(projectName, path, args);
   }
 }
diff --git a/src/main/java/com/googlesource/gerrit/plugins/hooks/TopicEdited.java b/src/main/java/com/googlesource/gerrit/plugins/hooks/TopicEdited.java
index e608694..62407dd 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/hooks/TopicEdited.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/hooks/TopicEdited.java
@@ -21,7 +21,7 @@
 
 @Singleton
 class TopicEdited implements TopicEditedListener {
-  private final AsynchronousHook hook;
+  private final Hook hook;
   private final HookFactory hookFactory;
 
   @Inject
@@ -43,6 +43,6 @@
     args.add("--old-topic", event.getOldTopic());
     args.add("--new-topic", event.getChange().topic);
 
-    hook.submit(c.project, args);
+    hook.execute(c.project, args);
   }
 }