diff --git a/gerrit-gwtexpui/src/main/java/com/google/gwtexpui/safehtml/client/SafeHtml.java b/gerrit-gwtexpui/src/main/java/com/google/gwtexpui/safehtml/client/SafeHtml.java
index 2a1ddc0ce1..5b3b9b607a 100644
--- a/gerrit-gwtexpui/src/main/java/com/google/gwtexpui/safehtml/client/SafeHtml.java
+++ b/gerrit-gwtexpui/src/main/java/com/google/gwtexpui/safehtml/client/SafeHtml.java
@@ -28,8 +28,9 @@ import java.util.Iterator;
 import java.util.List;
 
 /** Immutable string safely placed as HTML without further escaping. */
-@SuppressWarnings("serial")
 public abstract class SafeHtml implements com.google.gwt.safehtml.shared.SafeHtml {
+  private static final long serialVersionUID = 1L;
+
   public static final SafeHtmlResources RESOURCES;
 
   static {
diff --git a/gerrit-gwtexpui/src/main/java/com/google/gwtexpui/safehtml/client/SafeHtmlBuilder.java b/gerrit-gwtexpui/src/main/java/com/google/gwtexpui/safehtml/client/SafeHtmlBuilder.java
index a9269063ae..cde0f2af75 100644
--- a/gerrit-gwtexpui/src/main/java/com/google/gwtexpui/safehtml/client/SafeHtmlBuilder.java
+++ b/gerrit-gwtexpui/src/main/java/com/google/gwtexpui/safehtml/client/SafeHtmlBuilder.java
@@ -17,8 +17,9 @@ package com.google.gwtexpui.safehtml.client;
 import com.google.gwt.core.client.GWT;
 
 /** Safely constructs a {@link SafeHtml}, escaping user provided content. */
-@SuppressWarnings("serial")
 public class SafeHtmlBuilder extends SafeHtml {
+  private static final long serialVersionUID = 1L;
+
   private static final Impl impl;
 
   static {
diff --git a/gerrit-gwtexpui/src/main/java/com/google/gwtexpui/safehtml/client/SafeHtmlString.java b/gerrit-gwtexpui/src/main/java/com/google/gwtexpui/safehtml/client/SafeHtmlString.java
index 889509abb6..5335170499 100644
--- a/gerrit-gwtexpui/src/main/java/com/google/gwtexpui/safehtml/client/SafeHtmlString.java
+++ b/gerrit-gwtexpui/src/main/java/com/google/gwtexpui/safehtml/client/SafeHtmlString.java
@@ -14,8 +14,9 @@
 
 package com.google.gwtexpui.safehtml.client;
 
-@SuppressWarnings("serial")
 class SafeHtmlString extends SafeHtml {
+  private static final long serialVersionUID = 1L;
+
   private final String html;
 
   SafeHtmlString(String h) {
diff --git a/gerrit-gwtui/src/main/java/com/google/gerrit/client/change/RelatedChangesTab.java b/gerrit-gwtui/src/main/java/com/google/gerrit/client/change/RelatedChangesTab.java
index aa049cab51..c53427bee3 100644
--- a/gerrit-gwtui/src/main/java/com/google/gerrit/client/change/RelatedChangesTab.java
+++ b/gerrit-gwtui/src/main/java/com/google/gerrit/client/change/RelatedChangesTab.java
@@ -248,8 +248,9 @@ class RelatedChangesTab implements IsWidget {
     }
   }
 
-  @SuppressWarnings("serial")
   private class RowSafeHtml implements SafeHtml {
+    private static final long serialVersionUID = 1L;
+
     private String html;
     private ChangeAndCommit info;
     private final boolean notConnected;
diff --git a/gerrit-gwtui/src/main/java/com/google/gerrit/client/changes/RevisionInfoCache.java b/gerrit-gwtui/src/main/java/com/google/gerrit/client/changes/RevisionInfoCache.java
index 0b83119ae1..fde2b055c9 100644
--- a/gerrit-gwtui/src/main/java/com/google/gerrit/client/changes/RevisionInfoCache.java
+++ b/gerrit-gwtui/src/main/java/com/google/gerrit/client/changes/RevisionInfoCache.java
@@ -35,10 +35,11 @@ public class RevisionInfoCache {
 
   private final LinkedHashMap<PatchSet.Id, String> psToCommit;
 
-  @SuppressWarnings("serial")
   private RevisionInfoCache() {
     psToCommit =
         new LinkedHashMap<PatchSet.Id, String>(LIMIT) {
+          private static final long serialVersionUID = 1L;
+
           @Override
           protected boolean removeEldestEntry(Map.Entry<PatchSet.Id, String> e) {
             return size() > LIMIT;
diff --git a/gerrit-gwtui/src/main/java/com/google/gerrit/client/ui/NavigationTable.java b/gerrit-gwtui/src/main/java/com/google/gerrit/client/ui/NavigationTable.java
index 7e34730f6a..b2306a6b96 100644
--- a/gerrit-gwtui/src/main/java/com/google/gerrit/client/ui/NavigationTable.java
+++ b/gerrit-gwtui/src/main/java/com/google/gerrit/client/ui/NavigationTable.java
@@ -73,9 +73,10 @@ public abstract class NavigationTable<RowItem> extends FancyFlexTable<RowItem> {
     }
   }
 
-  @SuppressWarnings("serial")
   private static final LinkedHashMap<String, Object> savedPositions =
       new LinkedHashMap<String, Object>(10, 0.75f, true) {
+        private static final long serialVersionUID = 1L;
+
         @Override
         protected boolean removeEldestEntry(Entry<String, Object> eldest) {
           return size() >= 20;
diff --git a/gerrit-httpd/src/main/java/com/google/gerrit/httpd/auth/become/BecomeAnyAccountLoginServlet.java b/gerrit-httpd/src/main/java/com/google/gerrit/httpd/auth/become/BecomeAnyAccountLoginServlet.java
index 1f095e0540..de549a0efe 100644
--- a/gerrit-httpd/src/main/java/com/google/gerrit/httpd/auth/become/BecomeAnyAccountLoginServlet.java
+++ b/gerrit-httpd/src/main/java/com/google/gerrit/httpd/auth/become/BecomeAnyAccountLoginServlet.java
@@ -55,9 +55,10 @@ import org.eclipse.jgit.errors.ConfigInvalidException;
 import org.w3c.dom.Document;
 import org.w3c.dom.Element;
 
-@SuppressWarnings("serial")
 @Singleton
 class BecomeAnyAccountLoginServlet extends HttpServlet {
+  private static final long serialVersionUID = 1L;
+
   private final DynamicItem<WebSession> webSession;
   private final SchemaFactory<ReviewDb> schema;
   private final Accounts accounts;
diff --git a/gerrit-httpd/src/main/java/com/google/gerrit/httpd/auth/ldap/LdapLoginServlet.java b/gerrit-httpd/src/main/java/com/google/gerrit/httpd/auth/ldap/LdapLoginServlet.java
index 46714756fb..316bf5dfa9 100644
--- a/gerrit-httpd/src/main/java/com/google/gerrit/httpd/auth/ldap/LdapLoginServlet.java
+++ b/gerrit-httpd/src/main/java/com/google/gerrit/httpd/auth/ldap/LdapLoginServlet.java
@@ -47,9 +47,10 @@ import org.w3c.dom.Document;
 import org.w3c.dom.Element;
 
 /** Handles username/password based authentication against the directory. */
-@SuppressWarnings("serial")
 @Singleton
 class LdapLoginServlet extends HttpServlet {
+  private static final long serialVersionUID = 1L;
+
   private static final Logger log = LoggerFactory.getLogger(LdapLoginServlet.class);
 
   private final AccountManager accountManager;
diff --git a/gerrit-httpd/src/main/java/com/google/gerrit/httpd/gitweb/GitLogoServlet.java b/gerrit-httpd/src/main/java/com/google/gerrit/httpd/gitweb/GitLogoServlet.java
index af853cc333..2019dec073 100644
--- a/gerrit-httpd/src/main/java/com/google/gerrit/httpd/gitweb/GitLogoServlet.java
+++ b/gerrit-httpd/src/main/java/com/google/gerrit/httpd/gitweb/GitLogoServlet.java
@@ -32,9 +32,10 @@ import javax.servlet.http.HttpServlet;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 
-@SuppressWarnings("serial")
 @Singleton
 class GitLogoServlet extends HttpServlet {
+  private static final long serialVersionUID = 1L;
+
   private final long modified;
   private final byte[] raw;
 
diff --git a/gerrit-httpd/src/main/java/com/google/gerrit/httpd/gitweb/GitwebCssServlet.java b/gerrit-httpd/src/main/java/com/google/gerrit/httpd/gitweb/GitwebCssServlet.java
index 5e22081f72..83aed9c31e 100644
--- a/gerrit-httpd/src/main/java/com/google/gerrit/httpd/gitweb/GitwebCssServlet.java
+++ b/gerrit-httpd/src/main/java/com/google/gerrit/httpd/gitweb/GitwebCssServlet.java
@@ -32,10 +32,13 @@ import javax.servlet.http.HttpServlet;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 
-@SuppressWarnings("serial")
 abstract class GitwebCssServlet extends HttpServlet {
+  private static final long serialVersionUID = 1L;
+
   @Singleton
   static class Site extends GitwebCssServlet {
+    private static final long serialVersionUID = 1L;
+
     @Inject
     Site(SitePaths paths) throws IOException {
       super(paths.site_css);
@@ -44,6 +47,8 @@ abstract class GitwebCssServlet extends HttpServlet {
 
   @Singleton
   static class Default extends GitwebCssServlet {
+    private static final long serialVersionUID = 1L;
+
     @Inject
     Default(GitwebCgiConfig gwcc) throws IOException {
       super(gwcc.getGitwebCss());
diff --git a/gerrit-httpd/src/main/java/com/google/gerrit/httpd/gitweb/GitwebJavaScriptServlet.java b/gerrit-httpd/src/main/java/com/google/gerrit/httpd/gitweb/GitwebJavaScriptServlet.java
index 651b582fca..1b26f6d5ba 100644
--- a/gerrit-httpd/src/main/java/com/google/gerrit/httpd/gitweb/GitwebJavaScriptServlet.java
+++ b/gerrit-httpd/src/main/java/com/google/gerrit/httpd/gitweb/GitwebJavaScriptServlet.java
@@ -32,9 +32,10 @@ import javax.servlet.http.HttpServlet;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 
-@SuppressWarnings("serial")
 @Singleton
 class GitwebJavaScriptServlet extends HttpServlet {
+  private static final long serialVersionUID = 1L;
+
   private final long modified;
   private final byte[] raw;
 
diff --git a/gerrit-httpd/src/main/java/com/google/gerrit/httpd/gitweb/GitwebServlet.java b/gerrit-httpd/src/main/java/com/google/gerrit/httpd/gitweb/GitwebServlet.java
index 6a30000ee1..ec7c4778aa 100644
--- a/gerrit-httpd/src/main/java/com/google/gerrit/httpd/gitweb/GitwebServlet.java
+++ b/gerrit-httpd/src/main/java/com/google/gerrit/httpd/gitweb/GitwebServlet.java
@@ -84,9 +84,10 @@ import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 /** Invokes {@code gitweb.cgi} for the project given in {@code p}. */
-@SuppressWarnings("serial")
 @Singleton
 class GitwebServlet extends HttpServlet {
+  private static final long serialVersionUID = 1L;
+
   private static final Logger log = LoggerFactory.getLogger(GitwebServlet.class);
 
   private static final String PROJECT_LIST_ACTION = "project_list";
diff --git a/gerrit-httpd/src/main/java/com/google/gerrit/httpd/raw/CatServlet.java b/gerrit-httpd/src/main/java/com/google/gerrit/httpd/raw/CatServlet.java
index 08b42e5c7c..d28e582696 100644
--- a/gerrit-httpd/src/main/java/com/google/gerrit/httpd/raw/CatServlet.java
+++ b/gerrit-httpd/src/main/java/com/google/gerrit/httpd/raw/CatServlet.java
@@ -48,9 +48,10 @@ import org.eclipse.jgit.lib.ObjectId;
  * this site, and will execute it with the site's own protection domain. This opens a massive
  * security hole so we package the content into a zip file.
  */
-@SuppressWarnings("serial")
 @Singleton
 public class CatServlet extends HttpServlet {
+  private static final long serialVersionUID = 1L;
+
   private final Provider<ReviewDb> requestDb;
   private final Provider<CurrentUser> userProvider;
   private final ChangeEditUtil changeEditUtil;
diff --git a/gerrit-httpd/src/main/java/com/google/gerrit/httpd/raw/HostPageServlet.java b/gerrit-httpd/src/main/java/com/google/gerrit/httpd/raw/HostPageServlet.java
index 51340ae578..9818a34bb9 100644
--- a/gerrit-httpd/src/main/java/com/google/gerrit/httpd/raw/HostPageServlet.java
+++ b/gerrit-httpd/src/main/java/com/google/gerrit/httpd/raw/HostPageServlet.java
@@ -67,9 +67,10 @@ import org.w3c.dom.Element;
 import org.w3c.dom.Node;
 
 /** Sends the Gerrit host page to clients. */
-@SuppressWarnings("serial")
 @Singleton
 public class HostPageServlet extends HttpServlet {
+  private static final long serialVersionUID = 1L;
+
   private static final Logger log = LoggerFactory.getLogger(HostPageServlet.class);
 
   private static final String HPD_ID = "gerrit_hostpagedata";
diff --git a/gerrit-httpd/src/main/java/com/google/gerrit/httpd/raw/LegacyGerritServlet.java b/gerrit-httpd/src/main/java/com/google/gerrit/httpd/raw/LegacyGerritServlet.java
index 10735a5154..c34b3cb936 100644
--- a/gerrit-httpd/src/main/java/com/google/gerrit/httpd/raw/LegacyGerritServlet.java
+++ b/gerrit-httpd/src/main/java/com/google/gerrit/httpd/raw/LegacyGerritServlet.java
@@ -34,9 +34,10 @@ import javax.servlet.http.HttpServletResponse;
  * as it would lose any history token that appears in the URL. Instead we send an HTML page which
  * instructs the browser to replace the URL, but preserve the history token.
  */
-@SuppressWarnings("serial")
 @Singleton
 public class LegacyGerritServlet extends HttpServlet {
+  private static final long serialVersionUID = 1L;
+
   private final byte[] raw;
   private final byte[] compressed;
 
diff --git a/gerrit-httpd/src/main/java/com/google/gerrit/httpd/raw/SshInfoServlet.java b/gerrit-httpd/src/main/java/com/google/gerrit/httpd/raw/SshInfoServlet.java
index 55bc2a6c1b..d68b0093c8 100644
--- a/gerrit-httpd/src/main/java/com/google/gerrit/httpd/raw/SshInfoServlet.java
+++ b/gerrit-httpd/src/main/java/com/google/gerrit/httpd/raw/SshInfoServlet.java
@@ -46,9 +46,10 @@ import javax.servlet.http.HttpServletResponse;
  *  Port 8010
  * }</pre>
  */
-@SuppressWarnings("serial")
 @Singleton
 public class SshInfoServlet extends HttpServlet {
+  private static final long serialVersionUID = 1L;
+
   private final SshInfo sshd;
 
   @Inject
diff --git a/gerrit-httpd/src/main/java/com/google/gerrit/httpd/restapi/RestApiServlet.java b/gerrit-httpd/src/main/java/com/google/gerrit/httpd/restapi/RestApiServlet.java
index 7684bec7bd..f73e27d0ba 100644
--- a/gerrit-httpd/src/main/java/com/google/gerrit/httpd/restapi/RestApiServlet.java
+++ b/gerrit-httpd/src/main/java/com/google/gerrit/httpd/restapi/RestApiServlet.java
@@ -1295,8 +1295,9 @@ public class RestApiServlet extends HttpServlet {
     return new TemporaryBuffer.Heap(est, max);
   }
 
-  @SuppressWarnings("serial")
   private static class AmbiguousViewException extends Exception {
+    private static final long serialVersionUID = 1L;
+
     AmbiguousViewException(String message) {
       super(message);
     }
diff --git a/gerrit-httpd/src/main/java/com/google/gerrit/httpd/rpc/GerritJsonServlet.java b/gerrit-httpd/src/main/java/com/google/gerrit/httpd/rpc/GerritJsonServlet.java
index 178cda9358..d3d49cbca3 100644
--- a/gerrit-httpd/src/main/java/com/google/gerrit/httpd/rpc/GerritJsonServlet.java
+++ b/gerrit-httpd/src/main/java/com/google/gerrit/httpd/rpc/GerritJsonServlet.java
@@ -42,8 +42,9 @@ import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 /** Base JSON servlet to ensure the current user is not forged. */
-@SuppressWarnings("serial")
 final class GerritJsonServlet extends JsonServlet<GerritJsonServlet.GerritCall> {
+  private static final long serialVersionUID = 1L;
+
   private static final Logger log = LoggerFactory.getLogger(GerritJsonServlet.class);
   private static final ThreadLocal<GerritCall> currentCall = new ThreadLocal<>();
   private static final ThreadLocal<MethodHandle> currentMethod = new ThreadLocal<>();
diff --git a/gerrit-openid/src/main/java/com/google/gerrit/httpd/auth/openid/LoginForm.java b/gerrit-openid/src/main/java/com/google/gerrit/httpd/auth/openid/LoginForm.java
index 6202cfc65d..b083d0158d 100644
--- a/gerrit-openid/src/main/java/com/google/gerrit/httpd/auth/openid/LoginForm.java
+++ b/gerrit-openid/src/main/java/com/google/gerrit/httpd/auth/openid/LoginForm.java
@@ -53,9 +53,10 @@ import org.w3c.dom.Document;
 import org.w3c.dom.Element;
 
 /** Handles OpenID based login flow. */
-@SuppressWarnings("serial")
 @Singleton
 class LoginForm extends HttpServlet {
+  private static final long serialVersionUID = 1L;
+
   private static final Logger log = LoggerFactory.getLogger(LoginForm.class);
   private static final ImmutableMap<String, String> ALL_PROVIDERS =
       ImmutableMap.of(
diff --git a/gerrit-openid/src/main/java/com/google/gerrit/httpd/auth/openid/OpenIdLoginServlet.java b/gerrit-openid/src/main/java/com/google/gerrit/httpd/auth/openid/OpenIdLoginServlet.java
index a97e8aeb08..1b0fe9efe2 100644
--- a/gerrit-openid/src/main/java/com/google/gerrit/httpd/auth/openid/OpenIdLoginServlet.java
+++ b/gerrit-openid/src/main/java/com/google/gerrit/httpd/auth/openid/OpenIdLoginServlet.java
@@ -23,9 +23,10 @@ import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 
 /** Handles the {@code /OpenID} URL for web based single-sign-on. */
-@SuppressWarnings("serial")
 @Singleton
 class OpenIdLoginServlet extends HttpServlet {
+  private static final long serialVersionUID = 1L;
+
   private final OpenIdServiceImpl impl;
 
   @Inject
diff --git a/gerrit-server/src/main/java/com/google/gerrit/server/account/AccountDirectory.java b/gerrit-server/src/main/java/com/google/gerrit/server/account/AccountDirectory.java
index 5c14c9450c..6e5b42ee05 100644
--- a/gerrit-server/src/main/java/com/google/gerrit/server/account/AccountDirectory.java
+++ b/gerrit-server/src/main/java/com/google/gerrit/server/account/AccountDirectory.java
@@ -50,8 +50,9 @@ public abstract class AccountDirectory {
   public abstract void fillAccountInfo(Iterable<? extends AccountInfo> in, Set<FillOptions> options)
       throws DirectoryException;
 
-  @SuppressWarnings("serial")
   public static class DirectoryException extends Exception {
+    private static final long serialVersionUID = 1L;
+
     public DirectoryException(String message, Throwable why) {
       super(message, why);
     }
diff --git a/gerrit-server/src/main/java/com/google/gerrit/server/config/AllProjectsName.java b/gerrit-server/src/main/java/com/google/gerrit/server/config/AllProjectsName.java
index 198d5c5e8e..7719e38dbb 100644
--- a/gerrit-server/src/main/java/com/google/gerrit/server/config/AllProjectsName.java
+++ b/gerrit-server/src/main/java/com/google/gerrit/server/config/AllProjectsName.java
@@ -17,8 +17,9 @@ package com.google.gerrit.server.config;
 import com.google.gerrit.reviewdb.client.Project;
 
 /** Special name of the project that all projects derive from. */
-@SuppressWarnings("serial")
 public class AllProjectsName extends Project.NameKey {
+  private static final long serialVersionUID = 1L;
+
   public AllProjectsName(String name) {
     super(name);
   }
diff --git a/gerrit-server/src/main/java/com/google/gerrit/server/config/AllUsersName.java b/gerrit-server/src/main/java/com/google/gerrit/server/config/AllUsersName.java
index ff28be4660..22d29a4fef 100644
--- a/gerrit-server/src/main/java/com/google/gerrit/server/config/AllUsersName.java
+++ b/gerrit-server/src/main/java/com/google/gerrit/server/config/AllUsersName.java
@@ -17,8 +17,9 @@ package com.google.gerrit.server.config;
 import com.google.gerrit.reviewdb.client.Project;
 
 /** Special name of the project in which meta data for all users is stored. */
-@SuppressWarnings("serial")
 public class AllUsersName extends Project.NameKey {
+  private static final long serialVersionUID = 1L;
+
   public AllUsersName(String name) {
     super(name);
   }
diff --git a/gerrit-server/src/main/java/com/google/gerrit/server/documentation/QueryDocumentationExecutor.java b/gerrit-server/src/main/java/com/google/gerrit/server/documentation/QueryDocumentationExecutor.java
index eef6d3509c..73c2b5ead8 100644
--- a/gerrit-server/src/main/java/com/google/gerrit/server/documentation/QueryDocumentationExecutor.java
+++ b/gerrit-server/src/main/java/com/google/gerrit/server/documentation/QueryDocumentationExecutor.java
@@ -130,8 +130,9 @@ public class QueryDocumentationExecutor {
     return parser != null && searcher != null;
   }
 
-  @SuppressWarnings("serial")
   public static class DocQueryException extends Exception {
+    private static final long serialVersionUID = 1L;
+
     DocQueryException() {}
 
     DocQueryException(String msg) {
diff --git a/gerrit-server/src/main/java/com/google/gerrit/server/project/RuleEvalException.java b/gerrit-server/src/main/java/com/google/gerrit/server/project/RuleEvalException.java
index 9dae11c4d6..d2af2a3c7d 100644
--- a/gerrit-server/src/main/java/com/google/gerrit/server/project/RuleEvalException.java
+++ b/gerrit-server/src/main/java/com/google/gerrit/server/project/RuleEvalException.java
@@ -14,8 +14,9 @@
 
 package com.google.gerrit.server.project;
 
-@SuppressWarnings("serial")
 public class RuleEvalException extends Exception {
+  private static final long serialVersionUID = 1L;
+
   public RuleEvalException(String message) {
     super(message);
   }