JAVA实现发送邮件功能

话不多说，直接上代码！！！
/*
　　新建传输对象类
*/
import lombok.*;
import java.util.List;
import java.util.Map;

@Getter
@Setter
@AllArgsConstructor
@NoArgsConstructor
@ToString
@Builder
public class SapSendMessageVO {

    // 发件人的邮箱的服务器地址
    private String emailSMTPHost;
    // 使用的协议
    private String protocol;
    // 发送人邮箱
    private String SenderEmail;
    // 发件人姓名
    private String SenderName;
    // 发送人邮箱授权码
    private String senderCode;
    // 收件人邮箱
    private List<Map<String,String>> receiveMailAccount;
    // 抄送人邮箱
    private List<Map<String,String>> ccMailAccount;
    // 文件名称
    private String fileName;
    // 附件base64
    private String file;

}


/*
　　创建邮件信息方法
*/

private static MimeMessage createMimeMessage(Session session,SapSendMessageVO sapSendMessageVO) throws Exception {
    // 1. 创建一封邮件
    MimeMessage message = new MimeMessage(session);
    // 2. From: 发件人
    message.setFrom(new InternetAddress(sapSendMessageVO.getSenderEmail(), sapSendMessageVO.getSenderName(), "UTF-8"));
    // 3. MimeMessage.RecipientType.TO：收件类型；MimeMessage.RecipientType.CC：抄送类型；MimeMessage.RecipientType.BCC：密送类型
    List<Map<String,String>> recList = sapSendMessageVO.getReceiveMailAccount();
    List<Map<String,String>> ccList = sapSendMessageVO.getCcMailAccount();
    if (recList.size() > 0) {
        for (Map<String,String> map : recList) {
            message.addRecipient(MimeMessage.RecipientType.TO, new InternetAddress(map.get("recAddresses"), map.get("recName"), "UTF-8"));
        }
    } else {
        throw new CommonException("邮件必须要有收件人！");
    }
    if (ccList.size() > 0) {
        for (Map<String,String> map : ccList) {
            message.addRecipient(MimeMessage.RecipientType.CC, new InternetAddress(map.get("ccAddresses"), map.get("ccName"), "UTF-8"));
        }
    }
    // 4. Subject: 邮件主题
    message.setSubject("这是邮件的主题", "UTF-8");
    // 5. Content: 邮件正文（可以使用html标签）
    message.setContent("这是邮件正文", "text/html;charset=UTF-8");
    // 6. 附件
    // 将base64格式的文件解码，写入指定地址
    String filePath = "/home/jiantou/tkjt/one-contract/sapEmail/" + File.separator + sapSendMessageVO.getFileName();
    // String filePath = "D:\\file\\"+sapSendMessageVO.getFileName();
    try {
        byte[] buffer = new BASE64Decoder().decodeBuffer(sapSendMessageVO.getFile());
        for(int i =0 ; i < buffer.length ;i++) {
            if(buffer[i] < 0) {
                buffer[i] += 256;
            }
        }
        FileOutputStream out = new FileOutputStream(filePath);
        out.write(buffer);
        out.close();
    } catch (Exception e) {
        e.printStackTrace();
    }
    MimeMultipart multipart = new MimeMultipart();
    MimeBodyPart file1 = new MimeBodyPart();
    DataHandler handler = new DataHandler(new FileDataSource(filePath));
    file1.setDataHandler(handler);
    //对文件名进行编码，防止出现乱码
    String fileName = MimeUtility.encodeWord(sapSendMessageVO.getFileName(), "utf-8", "B");
    file1.setFileName(fileName);
    multipart.addBodyPart(file1);
    message.setContent(multipart);
    // 6. 设置发件时间
    message.setSentDate(new Date());
    // 7. 保存设置
    message.saveChanges();
    return message;
}

/*
　　发送邮件方法
*/

public void sapSendMessage(SapSendMessageVO sapSendMessageVO) {
    log.info("=========== sap调用接口，开始发送邮件 =========");
    try {
        Properties props = new Properties();
        props.setProperty("mail.transport.protocol", sapSendMessageVO.getProtocol());// 使用的协议
        props.setProperty("mail.smtp.host", sapSendMessageVO.getEmailSMTPHost());// 发件人的邮箱的SMTP服务器地址
        props.setProperty("mail.smtp.auth", "true");// 需要请求认证
        Session session = Session.getInstance(props);//得到会话对象实例
        session.setDebug(true);//是否打印详细日志
        MimeMessage message = createMimeMessage(session,sapSendMessageVO);//获取邮件对象（封装了一个方法）
        Transport transport = session.getTransport();
        transport.connect(sapSendMessageVO.getSenderEmail(), sapSendMessageVO.getSenderCode());//连接发送人的邮箱账户
        // 6. 发送邮件, 发到所有的收件地址, message.getAllRecipients() 获取到的是在创建邮件对象时添加的所有收件人, 抄送人
        log.info("======== 发送邮件地址数量为： ======="+message.getAllRecipients().length);
        log.info("======== 发送邮件地址为： ======="+message.getAllRecipients().toString());
        transport.sendMessage(message, message.getAllRecipients());
        // 7. 关闭连接
        transport.close();

        log.info("邮件发送成功");
    } catch (Exception e) {
        log.error("发送邮件失败");
    }
}