定时发送邮件以及数据导出excel作为附件

定时发送邮件以及数据导出excel作为附件

这次要求每天定时统计前一天的领券名单，结果导出成excel并且自动发送邮件

• 使用 ScheduledExecutorService 实现

Maven

<dependency>
            <groupId>javax.mail</groupId>
            <artifactId>mail</artifactId>
            <version>1.5.0-b01</version>
        </dependency>
        <dependency>
            <groupId>net.sourceforge.jexcelapi</groupId>
            <artifactId>jxl</artifactId>
            <version>2.5.7</version>
        </dependency>

定时器设置

然后放入监听中MailUtil.init();

public static void init() {
    ScheduledExecutorService pool = Executors.newScheduledThreadPool(1);
    long oneDay = 24 * 60 * 60 * 1000;
    long initDelay = TimeUtil.getTimeMillis("02:17:00") - System.currentTimeMillis();
    initDelay = initDelay > 0 ? initDelay : oneDay + initDelay;
    pool.scheduleAtFixedRate(new TimerTask() {
      @Override
      public void run() {
        try {
          String to = ConfigLoader.getInstance().getProperty("MAIL_TO");
          String subject = ConfigLoader.getInstance().getProperty("MAIL_SUBJECT");
          long startTime = TimeUtil.getStartTime();
          long endTime = TimeUtil.getEndTime();
          logger.info("startTime = " + startTime + " endTime = " + endTime);

          List<DataEntity> list = dao.queryMobileList(startTime, endTime);
          long time = System.currentTimeMillis() - 60 * 60 * 24 * 1000;
          SimpleDateFormat formatter = new SimpleDateFormat("MMdd");
          subject = formatter.format(time) + subject;
          String filePath = exportExcel(list, formatter.format(time));
          List<File> fList = new Vector<File>();
          fList.add(new File(filePath));
          MailUtil.send(to, subject, subject, fList);
        } catch (Throwable t) {
          logger.error(" sendEmail fail ");
        }
      }
    }, initDelay, oneDay, TimeUnit.MILLISECONDS);
  }

数据导出Excel

public static String exportExcel(List<DataEntity> list, String fileName) throws IOException {
    WritableWorkbook wwb = null;
    File file = new File(PATH + fileName + ".xls");
    if (!file.exists()) {
      file.createNewFile();
    }
    wwb = Workbook.createWorkbook(file);

    WritableSheet ws = wwb.createSheet("***名单", 0);

    Label labelId = new Label(0, 0, "序号");
    Label labelMobile = new Label(1, 0, "手机号");
    Label labelIp = new Label(2, 0, "ip地址");

    try {
      ws.addCell(labelId);
      ws.addCell(labelMobile);
      ws.addCell(labelIp);
    } catch (RowsExceededException e) {
      e.printStackTrace();
    } catch (WriteException e) {
      e.printStackTrace();
    }
    for (int i = 0; i < list.size(); i++) {

      Label labelId_i = new Label(0, i + 1, list.get(i).getId() + "");
      Label labelMobile_i = new Label(1, i + 1, list.get(i).getMobile());
      Label labelIp_i = new Label(2, i + 1, list.get(i).getIp());
      try {
        ws.addCell(labelId_i);
        ws.addCell(labelMobile_i);
        ws.addCell(labelIp_i);
      } catch (RowsExceededException e) {
        e.printStackTrace();
      } catch (WriteException e) {
        e.printStackTrace();
      }
    }

    wwb.write();
    try {
      wwb.close();
    } catch (WriteException e) {
      e.printStackTrace();
    }
    return PATH + fileName + ".xls";
  }

发送邮件

public static void send(String to, String subject, String body, List<File> files)
      throws Exception {
    List<InternetAddress> addresses = new Vector<InternetAddress>();
    if (StringUtil.isNotNull(to)) {
      String[] arr = to.trim().split(",");
      for (String str : arr) {
        if (StringUtil.isNotNull(str)) {
          addresses.add(new InternetAddress(str.trim()));
        }
      }
    }
    if (addresses.isEmpty()) {
      throw new Exception("None receiver! The program will be exit!");
    }
    if (StringUtil.isNull(subject)) {
      subject = "This is a Default Subject";
    }
    List<MimeBodyPart> mbps = new Vector<MimeBodyPart>();
    if (files != null && !files.isEmpty()) {
      for (File f : files) {
        if (!f.exists())
          continue;

        MimeBodyPart mbp = new MimeBodyPart();
        FileDataSource fds = new FileDataSource(f.getAbsolutePath());
        mbp.setDataHandler(new DataHandler(fds));
        mbp.setFileName(MimeUtility.encodeText(fds.getName()));
        mbps.add(mbp);
      }
    }
    if (body == "" || body == null)
      body = "";
    logger.info("subject = " + subject + " body = " + body + " addresses = " + addresses);
    sendMail(subject, body, addresses, mbps);
  }

  private static void sendMail(String subject, String body, List<InternetAddress> addresses,
      List<MimeBodyPart> mbps) throws Exception {
    String host = ConfigLoader.getInstance().getProperty("SMTP_HOST");
    String userName = ConfigLoader.getInstance().getProperty("SMTP_USER");
    String password = ConfigLoader.getInstance().getProperty("SMTP_PASSWORD");
    String userMail = ConfigLoader.getInstance().getProperty("SMTP_MAIL");

    if (StringUtil.isNull(host) || StringUtil.isNull(userName) || StringUtil.isNull(password)
        || StringUtil.isNull(userMail))
      throw new Exception(
          "Invalid params : " + host + "," + userName + "," + password + "," + userMail);

    Properties props = System.getProperties();
    props.put("mail.smtp.host", host);
    props.put("mail.smtp.auth", "true");
    Session session = Session.getDefaultInstance(props, null);
    MimeMessage msg = new MimeMessage(session);
    msg.setFrom(new InternetAddress(userMail));
    msg.addRecipients(Message.RecipientType.TO, addresses.toArray(new InternetAddress[] {}));
    msg.setSubject(subject);
    msg.setSentDate(new Date());
    if (mbps.isEmpty()) {
      msg.setText(body);
    } else {
      Multipart mp = new MimeMultipart();
      for (MimeBodyPart part : mbps) {
        mp.addBodyPart(part);
      }
      if (StringUtil.isNotNull(body)) {
        BodyPart messageBodyPart = new MimeBodyPart();
        messageBodyPart.setText(body);
        mp.addBodyPart(messageBodyPart);
      }
      msg.setContent(mp);
    }
    msg.saveChanges();

    int maxRetries = 10;
    int retryCount = 0;
    while (true) {
      try {
        Transport transport = session.getTransport("smtp");
        transport.connect(host, userName, password);
        transport.sendMessage(msg, msg.getRecipients(Message.RecipientType.TO));
        transport.close();
        break;
      } catch (Exception e) {
        if (e instanceof SocketException && retryCount < maxRetries) {
          retryCount++;
          logger.error("send mail {} failed {}, {} ", subject, retryCount, e.getMessage());
          continue;
        }
        throw e;
      }
    }
  }