前言

在许多企业级项目中，需要用到邮件发送的功能，如：

1. 注册用户时需要邮箱发送验证
2. 用户生日时发送邮件通知祝贺

3. 发送邮件给用户等

   创建工程导入依赖

<!-- 邮箱发送依赖 -->
<dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-mail</artifactId>
</dependency>
<!-- 小火龙代码简化 -->
<dependency><groupId>org.projectlombok</groupId><artifactId>lombok</artifactId><version>1.18.8</version>
</dependency>

本工程依赖于SpringBoot,是基于SpringBoot再次对邮箱发送进行了一次封装。

创建Application.properties

# JavaMailSender 邮件发送的配置
spring.mail.host=smtp.qq.com
spring.mail.username=lovelyWu98k@qq.com
#授权码
spring.mail.password=
spring.mail.properties.mail.smtp.auth=true
spring.mail.properties.mail.smtp.starttls.enable=true
spring.mail.properties.mail.smtp.starttls.required=true
spring.mail.default-encoding=UTF-8

封装邮箱发送工具类

创建邮箱信息实体类，如下：

/*** 邮件信息实体** @author:伍梓涛* @version:1.0.0* @Modified By:SimpleWu* @CopyRright (c)2019-:YUM架构平台*/
@Data
public class MailEntity {private String to; //收件人private String subject;//标题private String text;//正文private boolean isHtml = false;//是否html邮件private List<String> files;//附件地址private Date sentDate;//发送时间}

创建邮箱信息实体类工具，快捷创建邮件信息

/*** 邮箱发送信息统一处理封装** @author:伍梓涛* @version:1.0.0* @Modified By:SimpleWu* @CopyRright (c)2019-:YUM架构平台*/
@Slf4j
public class MailEntityHelper {public static MimeMessageHelper craeteMessageHelper(MimeMessage mimeMessage, MailEntity mailBean) throws MessagingException {MimeMessageHelper mimeMessageHelper = new MimeMessageHelper(mimeMessage, true);// mimeMessageHelper.setFrom(emailSender);//发件人mimeMessageHelper.setTo(mailBean.getTo());//收件人mimeMessageHelper.setSubject(mailBean.getSubject());//标题mimeMessageHelper.setText(mailBean.getText(), mailBean.isHtml());//是否htmlmimeMessageHelper.setSentDate(mailBean.getSentDate() == null ? new Date() : mailBean.getSentDate());// 客户端邮箱发送时间if (mailBean.getFiles() != null && mailBean.getFiles().size() > 0) {//附件添加mailBean.getFiles().forEach(filename -> {String ext = filename.substring(filename.lastIndexOf(".") + 1, filename.length());File diskfile = new File(filename);try {mimeMessageHelper.addAttachment(diskfile.getName(), diskfile);} catch (MessagingException e) {e.printStackTrace();log.error("设置附件失败:{}", mailBean);}});}return mimeMessageHelper;}}

创建邮箱发送工具类，进行邮箱发送：

/*** 邮箱发送工具类** @author:伍梓涛* @version:1.0.0* @Modified By:SimpleWu* @CopyRright (c)2019-:YUM架构平台*/
@Component
@Slf4j
public class MailHelper {@Autowiredprivate JavaMailSender javaMailSender;@Value("${spring.mail.username}")private String emailSender;private static MailHelper mailHelper;public MailHelper() {mailHelper = this;}/*** 构建静态获取实例** @return*/public static MailHelper buidler() {if (mailHelper == null) {return null;}return mailHelper;}/*public void sendSimpleMail(EmailContextPojo mailBean) {try {SimpleMailMessage simpleMailMessage = new SimpleMailMessage();//邮件发送人simpleMailMessage.setFrom(emailSender);//邮件接收人simpleMailMessage.setTo(mailBean.getTo());//邮件主题simpleMailMessage.setSubject(mailBean.getSubject());//邮件内容simpleMailMessage.setText(mailBean.getText());javaMailSender.send(simpleMailMessage);} catch (Exception e) {e.printStackTrace();log.error("邮件发送失败", e.getMessage());}}*/public void sendMail(MailEntity mailBean) {MimeMessage mimeMailMessage = null;try {mimeMailMessage = javaMailSender.createMimeMessage();MimeMessageHelper mimeMessageHelper = MailEntityHelper.craeteMessageHelper(mimeMailMessage, mailBean);mimeMessageHelper.setFrom(emailSender);//发件人javaMailSender.send(mimeMailMessage);} catch (Exception e) {log.error("邮件发送失败", e.getMessage());}}public void sendMail(MailEntity... mailBeans) {//批量发送集合List<MimeMessage> mimeMessages = new ArrayList<>(mailBeans.length);try {if (mailBeans != null || mailBeans.length > 0) {for (int i = 0; i < mailBeans.length; i++) {MimeMessage mimeMailMessage = javaMailSender.createMimeMessage();MimeMessageHelper messageHelper = MailEntityHelper.craeteMessageHelper(mimeMailMessage, mailBeans[i]);messageHelper.setFrom(emailSender);//发件人mimeMessages.add(mimeMailMessage);}}MimeMessage[] resultMessage = new MimeMessage[mimeMessages.size()];mimeMessages.toArray(resultMessage);javaMailSender.send((resultMessage));} catch (Exception e) {log.error("邮件发送失败", e.getMessage());}}}

在之前通过邮箱发送信息统一处理的工具类，对邮件信息实体进行封装后，这里就只需要传入对象参数即可。由于在这里使用的是SpringBoot已经封装好的，由于我们要把它当成工具类使用，每次需要注入并不方便。
所在在类中加了个静态对象，在Spring 容器实例化的时候给他初始化直接赋值给javaMailSender并且通过buidler()可以静态获取到实例对象，但是这样如果被重新创建对象后就会产生问题，所以最好在工具类中使用Spring 容器去获取 javaMailSender即可 。

发送邮件

1.发送普通邮件

 MailEntity emailContextPojo = new MailEntity();emailContextPojo.setSubject("Ycloud 邮箱标题");emailContextPojo.setText("Ycloud 邮箱正文");emailContextPojo.setTo(" 接收邮箱号 ");MailHelper.buidler().sendMail(emailContextPojo);

2.发送Html邮件

 emailContextPojo.setHtml(true);

只需要将信息实体类设置成true即可。
3.发送附件

emailContextPojo.setFiles(Arrays.asList("D:\\Yum系统架构平台\\004.高系统部署\\004.PXC\\部署手册.docx"));

只需要增加附件路径即可。
注: 请勿直接在项目中使用邮箱发送
可参考JOB实现定时发送邮件:https://www.cnblogs.com/SimpleWu/p/11341453.html
本文代码案例:https://github.com/450255266/open-doubi/tree/master/SpringBoot/email