diff --git a/java/com/google/gerrit/extensions/common/CommitInfo.java b/java/com/google/gerrit/extensions/common/CommitInfo.java
index a4e4071ca3..213b3669d2 100644
--- a/java/com/google/gerrit/extensions/common/CommitInfo.java
+++ b/java/com/google/gerrit/extensions/common/CommitInfo.java
@@ -14,7 +14,10 @@
 
 package com.google.gerrit.extensions.common;
 
+import static java.util.stream.Collectors.joining;
+
 import java.util.List;
+import java.util.Objects;
 
 public class CommitInfo {
   public String commit;
@@ -24,4 +27,40 @@ public class CommitInfo {
   public String subject;
   public String message;
   public List<WebLinkInfo> webLinks;
+
+  @Override
+  public boolean equals(Object o) {
+    if (!(o instanceof CommitInfo)) {
+      return false;
+    }
+    CommitInfo c = (CommitInfo) o;
+    return Objects.equals(commit, c.commit)
+        && Objects.equals(parents, c.parents)
+        && Objects.equals(author, c.author)
+        && Objects.equals(committer, c.committer)
+        && Objects.equals(subject, c.subject)
+        && Objects.equals(message, c.message)
+        && Objects.equals(webLinks, c.webLinks);
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(commit, parents, author, committer, subject, message, webLinks);
+  }
+
+  @Override
+  public String toString() {
+    // Using something like the raw commit format might be nice, but we can't depend on JGit here.
+    StringBuilder sb = new StringBuilder().append(getClass().getSimpleName()).append('{');
+    sb.append(commit);
+    sb.append(", parents=").append(parents.stream().map(p -> p.commit).collect(joining(", ")));
+    sb.append(", author=").append(author);
+    sb.append(", committer=").append(committer);
+    sb.append(", subject=").append(subject);
+    sb.append(", message=").append(message);
+    if (webLinks != null) {
+      sb.append(", webLinks=").append(webLinks);
+    }
+    return sb.append('}').toString();
+  }
 }
diff --git a/java/com/google/gerrit/extensions/common/GitPerson.java b/java/com/google/gerrit/extensions/common/GitPerson.java
index 98534176e7..904829c2c9 100644
--- a/java/com/google/gerrit/extensions/common/GitPerson.java
+++ b/java/com/google/gerrit/extensions/common/GitPerson.java
@@ -15,10 +15,42 @@
 package com.google.gerrit.extensions.common;
 
 import java.sql.Timestamp;
+import java.util.Objects;
 
 public class GitPerson {
   public String name;
   public String email;
   public Timestamp date;
   public int tz;
+
+  @Override
+  public boolean equals(Object o) {
+    if (!(o instanceof GitPerson)) {
+      return false;
+    }
+    GitPerson p = (GitPerson) o;
+    return Objects.equals(name, p.name)
+        && Objects.equals(email, p.email)
+        && Objects.equals(date, p.date)
+        && tz == p.tz;
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(name, email, date, tz);
+  }
+
+  @Override
+  public String toString() {
+    return getClass().getSimpleName()
+        + "{name="
+        + name
+        + ", email="
+        + email
+        + ", date="
+        + date
+        + ", tz="
+        + tz
+        + "}".toString();
+  }
 }
diff --git a/java/com/google/gerrit/extensions/common/WebLinkInfo.java b/java/com/google/gerrit/extensions/common/WebLinkInfo.java
index 4dd8f0259c..3af5aba236 100644
--- a/java/com/google/gerrit/extensions/common/WebLinkInfo.java
+++ b/java/com/google/gerrit/extensions/common/WebLinkInfo.java
@@ -15,6 +15,7 @@
 package com.google.gerrit.extensions.common;
 
 import com.google.gerrit.extensions.webui.WebLink.Target;
+import java.util.Objects;
 
 public class WebLinkInfo {
   public String name;
@@ -32,4 +33,35 @@ public class WebLinkInfo {
   public WebLinkInfo(String name, String imageUrl, String url) {
     this(name, imageUrl, url, Target.SELF);
   }
+
+  @Override
+  public boolean equals(Object o) {
+    if (!(o instanceof WebLinkInfo)) {
+      return false;
+    }
+    WebLinkInfo i = (WebLinkInfo) o;
+    return Objects.equals(name, i.name)
+        && Objects.equals(imageUrl, i.imageUrl)
+        && Objects.equals(url, i.url)
+        && Objects.equals(target, i.target);
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(name, imageUrl, url, target);
+  }
+
+  @Override
+  public String toString() {
+    return getClass().getSimpleName()
+        + "{name="
+        + name
+        + ", imageUrl="
+        + imageUrl
+        + ", url="
+        + url
+        + ", target"
+        + target
+        + "}".toString();
+  }
 }