This is Beta work, so we need to remove it from head in Github, and we are now working of a beta branch which has the change https://github.com/GoogleCloudPlatform/appengine-java-standard/tree/2.0.39-beta-wip

PiperOrigin-RevId: 800070758
Change-Id: I80c3330913f78ddf41d3ed2f77623c40c5b8668f

Author: ludoch

api/pom.xml

@@ -137,7 +137,7 @@
     </dependency>
     <dependency>
       <groupId>org.mockito</groupId>
-      <artifactId>mockito-core</artifactId>
+      <artifactId>mockito-junit-jupiter</artifactId>
       <scope>test</scope>
     </dependency>
     <dependency>

api/src/main/java/com/google/appengine/api/EnvironmentProvider.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2025 Google LLC
+ * Copyright 2021 Google LLC
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -16,31 +16,13 @@
 
 package com.google.appengine.api.mail;
 
-import com.google.appengine.api.EnvironmentProvider;
-
 /**
  * Factory for creating a {@link MailService}.
  */
 final class MailServiceFactoryImpl implements IMailServiceFactory {
 
-  private static final String APPENGINE_USE_SMTP_MAIL_SERVICE_ENV = "APPENGINE_USE_SMTP_MAIL_SERVICE";
-  private final EnvironmentProvider envProvider;
-
-  MailServiceFactoryImpl() {
-    this(new SystemEnvironmentProvider());
-  }
-
-  // For testing
-  MailServiceFactoryImpl(EnvironmentProvider envProvider) {
-    this.envProvider = envProvider;
-  }
-
   @Override
-  @SuppressWarnings("YodaCondition")
   public MailService getMailService() {
-    if ("true".equals(envProvider.getenv(APPENGINE_USE_SMTP_MAIL_SERVICE_ENV))) {
-      return new SmtpMailServiceImpl(envProvider);
-    }
     return new MailServiceImpl();
   }
 }

api/src/main/java/com/google/appengine/api/mail/MailServiceFactoryImpl.java

@@ -25,16 +25,15 @@
 import java.io.IOException;
 
 /**
- * This class implements raw access to the mail service. Applications that don't want to make use of
- * Sun's JavaMail can use it directly -- but they will forego the typing and convenience methods
- * that JavaMail provides.
+ * This class implements raw access to the mail service.
+ * Applications that don't want to make use of Sun's JavaMail
+ * can use it directly -- but they will forego the typing and
+ * convenience methods that JavaMail provides.
+ *
  */
 class MailServiceImpl implements MailService {
   static final String PACKAGE = "mail";
 
-  /** Default constructor. */
-  MailServiceImpl() {}
-
   /** {@inheritDoc} */
   @Override
   public void sendToAdmins(Message message)
@@ -48,7 +47,7 @@ public void send(Message message)
       throws IllegalArgumentException, IOException {
     doSend(message, false);
   }
-  
+
   /**
    * Does the actual sending of the message.
    * @param message The message to be sent.