java怎么实现发送邮件

import java.util.Properties;
import javax.mail.*;
import javax.mail.internet.InternetAddress;
import javax.mail.internet.MimeMessage;
public class EmailSender {
    public static void main(String[] args) {
        // 邮件服务器配置信息
        String host = "your_smtp_host";
        String username = "your_email_username";
        String password = "your_email_password";
        int port = 587; // SMTP端口号，一般为587
        // 发件人和收件人信息
        String from = "your_email@example.com";
        String to = "recipient@example.com";
        // 创建邮件会话
        Properties properties = new Properties();
        properties.put("mail.smtp.host", host);
        properties.put("mail.smtp.port", String.valueOf(port));
        properties.put("mail.smtp.auth", "true");
        properties.put("mail.smtp.starttls.enable", "true");
        Session session = Session.getInstance(properties, new Authenticator() {
            protected PasswordAuthentication getPasswordAuthentication() {
                return new PasswordAuthentication(username, password);
            }
        });
        try {
            // 创建邮件对象
            Message message = new MimeMessage(session);
            message.setFrom(new InternetAddress(from));
            message.setRecipients(Message.RecipientType.TO, InternetAddress.parse(to));
            message.setSubject("Test Email");
            message.setText("This is a test email sent from Java.");
            // 发送邮件
            Transport.send(message);
            System.out.println("Email sent successfully!");
        } catch (MessagingException e) {
            e.printStackTrace();
        }
    }
}