java发送邮件带附件怎么实现

在Java中发送带附件的邮件可以使用JavaMail API来实现。以下是一个示例代码：

import java.util.Properties; import javax.mail.Authenticator; import javax.mail.Message; import javax.mail.MessagingException; import javax.mail.PasswordAuthentication; import javax.mail.Session; import javax.mail.Transport; import javax.mail.internet.InternetAddress; import javax.mail.internet.MimeBodyPart; import javax.mail.internet.MimeMessage; import javax.mail.internet.MimeMultipart; import javax.activation.DataHandler; import javax.activation.DataSource; import javax.activation.FileDataSource;  public class EmailSender {     public static void main(String[] args) {         // 发件人邮箱和密码         final String username = "your_email@example.com";         final String password = "your_password";          // 发件人邮箱的 SMTP 服务器地址         final String smtpHost = "smtp.example.com";          // 收件人邮箱         String toEmail = "recipient@example.com";          // 创建邮件会话         Properties props = new Properties();         props.put("mail.smtp.auth", "true");         props.put("mail.smtp.host", smtpHost);         props.put("mail.smtp.port", "587");         props.put("mail.smtp.starttls.enable", "true");          Session session = Session.getInstance(props, new Authenticator() {             protected PasswordAuthentication getPasswordAuthentication() {                 return new PasswordAuthentication(username, password);             }         });          try {             // 创建邮件消息             Message message = new MimeMessage(session);             message.setFrom(new InternetAddress(username));             message.setRecipients(Message.RecipientType.TO, InternetAddress.parse(toEmail));             message.setSubject("JavaMail Attachment Example");              // 创建邮件内容             MimeMultipart multipart = new MimeMultipart();             MimeBodyPart messageBodyPart = new MimeBodyPart();             messageBodyPart.setText("This is a sample email with attachment.");              // 附件文件路径             String attachmentPath = "/path/to/attachment.txt";             // 创建附件             MimeBodyPart attachmentBodyPart = new MimeBodyPart();             DataSource source = new FileDataSource(attachmentPath);             attachmentBodyPart.setDataHandler(new DataHandler(source));             attachmentBodyPart.setFileName(source.getName());              // 将内容和附件添加到邮件中             multipart.addBodyPart(messageBodyPart);             multipart.addBodyPart(attachmentBodyPart);             message.setContent(multipart);              // 发送邮件             Transport.send(message);             System.out.println("Email sent successfully.");         } catch (MessagingException e) {             e.printStackTrace();         }     } } 

在上述代码中，你需要替换以下内容：

• your_email@example.com：发件人邮箱
• your_password：发件人邮箱密码
• smtp.example.com：发件人邮箱的 SMTP 服务器地址
• recipient@example.com：收件人邮箱
• /path/to/attachment.txt：附件的文件路径

确保你已经添加了javax.mail和activation依赖，以及正确配置了邮件服务器信息。