一, 简介

为什么会用到多邮箱发送? 在实际应用中,不管是腾讯邮箱,网易邮箱都有上限阈值,即使开通VIP也一样会遇到该问题;

各大邮箱每天发送数量限制:

在项目中, 经常会遇到 550连接频率受限的错误:

com.sun.mail.smtp.SMTPSendFailedException: 550 Connection frequency limited

二, 解决方法

既然遇到该问题,哪我们总不能不管吧,哪怎么解决该问题呢?

当然最简单的办法就是: 增加发送邮箱数量,轮流执行发送;

想想看,既然一个邮箱遭到限制, 那有10个邮箱轮流发送呢?发件数量将会是之前的10倍; 100个发送邮箱呢....

三, 具体实例

1, 引入Maven Jar包


                
     
      org.springframework.boot
                 
     
      spring-boot-starter-mail

2, 邮件发送接口

package com.richfun.wxappi.utils.email;/** * 多邮箱发送邮件 * */public interface EmailMoreService {    /**     * 发送文本邮件     * */    boolean sendSimpleMail(String to, String subject, String content);    /**     * 发送HTML邮件     * */    boolean sendHtmlMail(String to, String subject, String content);}

3, 邮件发送实现

package com.richfun.wxappi.utils.email;import com.richfun.wxappi.mapper.CommonDao;import com.richfun.wxappi.utils.Namespace;import org.slf4j.Logger;import org.slf4j.LoggerFactory;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.mail.SimpleMailMessage;import org.springframework.mail.javamail.JavaMailSenderImpl;import org.springframework.mail.javamail.MimeMessageHelper;import org.springframework.stereotype.Service;import javax.annotation.PostConstruct;import javax.mail.internet.MimeMessage;import java.util.List;import java.util.Map;import java.util.Properties;@Servicepublic class EmailMoreServiceImpl implements EmailMoreService {    private Logger logger = LoggerFactory.getLogger(getClass());    @Autowired    private CommonDao
     
      > commonDao;    private int emailId = 0;    private List
      
       
        > listEmail;    @PostConstruct    private void setListEmail() {        // 设置邮箱发送列表, 从数据库中获取可发送邮箱列表        logger.info("=== 初始化可发送邮箱列表 ===");        this.listEmail = commonDao.findByMapList(Namespace.EMAIL + "listEmail", null);        if (listEmail == null || listEmail.isEmpty()) {            logger.error("=== 可发送邮箱列表为NULL, 请检测代码 ===");        } else {            for (Map
        
          email : listEmail) {                logger.info("=== 可发送邮箱: " + email.get("email"));            }        }    }    private synchronized void setEmailId() {        // 设置下次可发送邮箱        boolean isMax = emailId == (listEmail.size()-1);        emailId = isMax ? 0 : emailId+1;    }    private synchronized Map
         
           getEmail() { // 获取当前可发送邮箱 Map
          
            email = listEmail.get(emailId); setEmailId(); return email; } private synchronized JavaMailSenderImpl getJavaMailSender() { // 获取邮箱发送实例 Map
           
             email = getEmail(); String host = email.get("host_addr").toString(); String username = email.get("email").toString(); String password = email.get("pwd").toString(); String sslPort = email.get("ssl_port").toString(); JavaMailSenderImpl javaMailSenderImpl = new JavaMailSenderImpl(); javaMailSenderImpl.setHost(host); javaMailSenderImpl.setUsername(username); javaMailSenderImpl.setPassword(password); javaMailSenderImpl.setDefaultEncoding("UTF-8"); Properties properties = new Properties(); properties.setProperty("mail.smtp.auth", "true"); properties.setProperty("mail.smtp.socketFactory.port", sslPort); properties.setProperty("mail.smtp.socketFactory.class", "javax.net.ssl.SSLSocketFactory"); javaMailSenderImpl.setJavaMailProperties(properties); return javaMailSenderImpl; } @Override public boolean sendSimpleMail(String to, String subject, String content) { logger.info("简单邮件开始发送"); try { JavaMailSenderImpl javaMailSender = getJavaMailSender(); String username = javaMailSender.getUsername(); logger.info("当前发送邮箱: " + username); SimpleMailMessage message = new SimpleMailMessage(); message.setFrom(username); message.setTo(to); message.setSubject(subject); message.setText(content); javaMailSender.send(message); logger.info("简单邮件发送成功"); return true; } catch (Exception e) { logger.error("简单邮件发送异常", e); e.printStackTrace(); } return false; } @Override public boolean sendHtmlMail(String to, String subject, String content) { logger.info("HTML邮件开始发送"); try { JavaMailSenderImpl javaMailSender = getJavaMailSender(); MimeMessage message = javaMailSender.createMimeMessage(); MimeMessageHelper messageHelper = new MimeMessageHelper(message, true); String username = javaMailSender.getUsername(); logger.info("当前发送邮箱: " + username); messageHelper.setFrom(username); messageHelper.setTo(to); messageHelper.setSubject(subject); messageHelper.setText(content, true); javaMailSender.send(message); logger.info("HTML邮件发送成功"); return true; } catch (Exception e) { logger.error("HTML邮件发送异常", e); e.printStackTrace(); } return false; }}