How to Send Email Using JSP and JavaMail API

Sending emails from a JSP page is very useful for contact forms, notifications, and automation in Java web applications. In this guide, you’ll learn how to send a simple text email using JSP + JavaMail API, step by step.

✅ Requirements
Before you begin, you need the following:

1. JavaMail API Library Download from the official GitHub:

JavaMail (javax.mail.jar):
[https://repo1.maven.org/maven2/com/sun/mail/javax.mail/1.6.2/javax.mail-1.6.2.jar]

1. JavaBeans Activation Framework (activation.jar) Download:

activation.jar:
[https://repo1.maven.org/maven2/com/sun/mail/javax.mail/1.6.2/javax.mail-1.6.2.jar]

📁 Place both JARs in your project’s WEB-INF/lib folder.

📝 Instructions to Use:
Download both .jar files.

Place them in your project’s WEB-INF/lib folder if using a Java web app.

Make sure your server (e.g., Apache Tomcat) loads them at runtime.

📄 Step-by-Step Implementation in JSP
Here’s a complete working example of sending an email from a sendmail.jsp file.

<%@ page import="java.util.*, javax.mail.*, javax.mail.internet.*" %>
<%
    final String senderEmail = "[e-mail]";
    final String senderPassword = "your_app_password"; // App Password, not Gmail password
    String recipient = "[e-mail]";
    String subject = "Test Mail from JSP";
    String messageText = "This is a test email sent from JSP page.";

    Properties props = new Properties();
    props.put("mail.smtp.host", "smtp.gmail.com");
    props.put("mail.smtp.port", "587");
    props.put("mail.smtp.auth", "true");
    props.put("mail.smtp.starttls.enable", "true");

    Session session = Session.getInstance(props,
        new javax.mail.Authenticator() {
            protected PasswordAuthentication getPasswordAuthentication() {
                return new PasswordAuthentication(senderEmail, senderPassword);
            }
        });

    try {
        Message message = new MimeMessage(session);
        message.setFrom(new InternetAddress(senderEmail));
        message.setRecipients(Message.RecipientType.TO, InternetAddress.parse(recipient));
        message.setSubject(subject);
        message.setText(messageText);
        Transport.send(message);

        out.println("<h3>Email sent successfully!</h3>");
    } catch (MessagingException e) {
        out.println("<h3>Error: " + e.getMessage() + "</h3>");
        e.printStackTrace(out);
    }
%>

🔐 Gmail App Password Setup
Since Google doesn't allow you to use your Gmail password directly, follow these steps:

Turn on 2-Step Verification for your Google account.

Go to: [https://myaccount.google.com/apppasswords]

Generate a new App Password.

Use this password in place of your Gmail password in the JSP code.

📌 Tips
Never use real credentials in public code.

Always handle exceptions gracefully.

For real-world projects, separate business logic (email sending) into a Servlet or Java Bean instead of putting it directly in JSP.
🧾 Summary
| Component | Description |
| -------------- | --------------------------------- |
| JSP Page | Sends email using JavaMail API |
| JavaMail Jar | javax.mail-1.6.2.jar |
| Activation Jar | activation-1.1.1.jar |
| SMTP Server | Gmail SMTP (smtp.gmail.com:587) |
| Authentication | Gmail App Password |