Appengine javax.mail

A great combination!

To use JavaMail with Google App Engine, you'll need to follow these steps:

1. Add the JavaMail dependency: In your pom.xml file (if you're using Maven) or your build.gradle file (if you're using Gradle), add the following dependency:

   
   <!-- Maven -->
   <dependency>
    <groupId>com.sun.mail</groupId>
    <artifactId>javax.mail</artifactId>
    <version>1.6.2</version>
   </dependency>

dependencies { implementation 'com.sun.mail:javax.mail:1.6.2' }

2. **Configure the JavaMail session**: In your App Engine application, create a JavaMail session by creating a `Session` object and setting the necessary properties. For example:
```java
import javax.mail.Session;
import javax.mail.Transport;
import javax.mail.internet.InternetAddress;
import javax.mail.internet.MimeMessage;

// Create a JavaMail session
Session session = Session.getInstance(new Properties(), new Authenticator() {
    @Override
    protected PasswordAuthentication getPasswordAuthentication() {
        return new PasswordAuthentication("[email protected]", "your-password");
    }
});

3. Use the JavaMail session to send emails: Use the Transport class to send emails. For example:

   
   // Create a MimeMessage object
   MimeMessage message = new MimeMessage(session);

// Set the sender and recipient message.setFrom(new InternetAddress("[email protected]")); message.addRecipient(Message.RecipientType.TO, new InternetAddress("[email protected]"));

// Set the subject and body message.setSubject("Hello from App Engine!"); message.setText("This is a test email from App Engine.");

// Send the email Transport.send(message);

4. **Handle exceptions**: Make sure to handle any exceptions that may occur during the email sending process. For example:
```java
try {
    Transport.send(message);
} catch (MessagingException e) {
    // Handle the exception
    System.out.println("Error sending email: " + e.getMessage());
}

5. Deploy your App Engine application: Once you've configured JavaMail and written the code to send emails, deploy your App Engine application to Google Cloud.

Some important notes:

• JavaMail is not supported by App Engine out of the box, so you'll need to add the dependency and configure it manually.
• App Engine has some limitations on email sending, such as a maximum of 100 emails per day per instance.
• You may need to use a third-party service, such as Sendgrid or Mailgun, if you need to send a large volume of emails or require more advanced features.