如何从Java发送SMTP消息？

   <dependency>
       <groupId>javax.mail</groupId>
       <artifactId>javax.mail-api</artifactId>
       <version>1.6.2</version>
    </dependency>
   <dependency>
       <groupId>com.sun.mail</groupId>
       <artifactId>javax.mail</artifactId>
       <version>1.6.2</version>
    </dependency>
</dependencies>

import javax.mail.*;
import javax.mail.internet.*;
import java.util.Properties;

public class SendEmail {

    public static void main(String[] args) {
        // 设置发件人、收件人和SMTP服务器信息。
        String from = "your_email@example.com";
        String password = "your_email_password";
        String to = "recipient@example.com";
        String host = "smtp.example.com";

        // 配置SMTP服务器属性。
        Properties props = new Properties();
        props.put("mail.smtp.host", host);
        props.put("mail.smtp.port", "587");
        props.put("mail.smtp.auth", "true");
        props.put("mail.smtp.starttls.enable", "true");

        // 获取默认的Session对象。
        Session session = Session.getInstance(props, new Authenticator() {
            @Override
            protected PasswordAuthentication getPasswordAuthentication() {
                return new PasswordAuthentication(from, password);
            }
        });

        try {
            // 创建一个消息。
            Message message = new MimeMessage(session);
            message.setFrom(new InternetAddress(from));
            message.setRecipients(Message.RecipientType.TO, InternetAddress.parse(to));
            message.setSubject("Testing Subject");
            message.setText("Dear Mail Recipient,\n\nThis is a test email sent through JavaMail API.\n\nBest regards,\nThe JavaMail Team");

            // 发送消息。
            Transport.send(message);
            System.out.println("Email sent successfully.");
        } catch (MessagingException e) {
            e.printStackTrace();
        }
    }
}