<dependency>
 <groupId>org.springframework.boot</groupId>
 <artifactId>spring-boot-starter-mail</artifactId>
</dependency>

spring:
 mail:
 # 郵件服務(wù)地址
 host: smtp.163.com
 # 端口,可不寫默認(rèn)
 port: 25
 # 編碼格式
 default-encoding: utf-8
 # 用戶名
 username: xxx@163.com
 # 授權(quán)碼，就是我們剛才準(zhǔn)備工作獲取的代碼
 password: xxx
 # 其它參數(shù)
 properties:
  mail:
  smtp:
   # 如果是用 SSL 方式，需要配置如下屬性,使用qq郵箱的話需要開啟
   ssl:
   enable: true
   required: true
   # 郵件接收時(shí)間的限制，單位毫秒
   timeout: 10000
   # 連接時(shí)間的限制，單位毫秒
   connectiontimeout: 10000
   # 郵件發(fā)送時(shí)間的限制，單位毫秒
   writetimeout: 10000

@Service
public class MailService {
 private static final Logger logger = LoggerFactory.getLogger(MailServiceImpl.class);

 @Autowired
 private JavaMailSender mailSender;

 private static final String SENDER = "xxx@163.com";

 /**
  * 發(fā)送普通郵件
  *
  * @param to  收件人
  * @param subject 主題
  * @param content 內(nèi)容
  */
 @Override
 public void sendSimpleMailMessge(String to, String subject, String content) {
  SimpleMailMessage message = new SimpleMailMessage();
  message.setFrom(SENDER);
  message.setTo(to);
  message.setSubject(subject);
  message.setText(content);
  try {
   mailSender.send(message);
  } catch (Exception e) {
   logger.error("發(fā)送簡(jiǎn)單郵件時(shí)發(fā)生異常!", e);
  }
 }

 /**
  * 發(fā)送 HTML 郵件
  *
  * @param to  收件人
  * @param subject 主題
  * @param content 內(nèi)容
  */
 @Override
 public void sendMimeMessge(String to, String subject, String content) {
  MimeMessage message = mailSender.createMimeMessage();
  try {
   //true表示需要?jiǎng)?chuàng)建一個(gè)multipart message
   MimeMessageHelper helper = new MimeMessageHelper(message, true);
   helper.setFrom(SENDER);
   helper.setTo(to);
   helper.setSubject(subject);
   helper.setText(content, true);
   mailSender.send(message);
  } catch (MessagingException e) {
   logger.error("發(fā)送MimeMessge時(shí)發(fā)生異常！", e);
  }
 }

 /**
  * 發(fā)送帶附件的郵件
  *
  * @param to  收件人
  * @param subject 主題
  * @param content 內(nèi)容
  * @param filePath 附件路徑
  */
 @Override
 public void sendMimeMessge(String to, String subject, String content, String filePath) {
  MimeMessage message = mailSender.createMimeMessage();
  try {
   //true表示需要?jiǎng)?chuàng)建一個(gè)multipart message
   MimeMessageHelper helper = new MimeMessageHelper(message, true);
   helper.setFrom(SENDER);
   helper.setTo(to);
   helper.setSubject(subject);
   helper.setText(content, true);

   FileSystemResource file = new FileSystemResource(new File(filePath));
   String fileName = file.getFilename();
   helper.addAttachment(fileName, file);

   mailSender.send(message);
  } catch (MessagingException e) {
   logger.error("發(fā)送帶附件的MimeMessge時(shí)發(fā)生異常！", e);
  }
 }

 /**
  * 發(fā)送帶靜態(tài)文件的郵件
  *
  * @param to  收件人
  * @param subject 主題
  * @param content 內(nèi)容
  * @param rscIdMap 需要替換的靜態(tài)文件
  */
 @Override
 public void sendMimeMessge(String to, String subject, String content, Map<String, String> rscIdMap) {
  MimeMessage message = mailSender.createMimeMessage();
  try {
   //true表示需要?jiǎng)?chuàng)建一個(gè)multipart message
   MimeMessageHelper helper = new MimeMessageHelper(message, true);
   helper.setFrom(SENDER);
   helper.setTo(to);
   helper.setSubject(subject);
   helper.setText(content, true);

   for (Map.Entry<String, String> entry : rscIdMap.entrySet()) {
    FileSystemResource file = new FileSystemResource(new File(entry.getValue()));
    helper.addInline(entry.getKey(), file);
   }
   mailSender.send(message);
  } catch (MessagingException e) {
   logger.error("發(fā)送帶靜態(tài)文件的MimeMessge時(shí)發(fā)生異常！", e);
  }
 }
}

@RunWith(SpringRunner.class)
@SpringBootTest
public class SpringbooEmailDemoApplicationTests {

 @Autowired
 private MailService mailService;

 private static final String TO = "xxx@qq.com";
 private static final String SUBJECT = "測(cè)試郵件";
 private static final String CONTENT = "test content";

 /**
  * 測(cè)試發(fā)送普通郵件
  */
 @Test
 public void sendSimpleMailMessage() {
  mailService.sendSimpleMailMessge(TO, SUBJECT, CONTENT);
 }

 /**
  * 測(cè)試發(fā)送html郵件
  */
 @Test
 public void sendHtmlMessage() {
  String htmlStr = "<h1>Test</h1>";
  mailService.sendMimeMessge(TO, SUBJECT, htmlStr);
 }

 /**
  * 測(cè)試發(fā)送帶附件的郵件
  * @throws FileNotFoundException
  */
 @Test
 public void sendAttachmentMessage() throws FileNotFoundException {
  File file = ResourceUtils.getFile("classpath:test.txt");
  String filePath = file.getAbsolutePath();
  mailService.sendMimeMessge(TO, SUBJECT, CONTENT, filePath);
 }

 /**
  * 測(cè)試發(fā)送帶附件的郵件
  * @throws FileNotFoundException
  */
 @Test
 public void sendPicMessage() throws FileNotFoundException {
  String htmlStr = "<html><body>測(cè)試：圖片1 <br> <img src=\'cid:pic1\'/> <br>圖片2 <br> <img src=\'cid:pic2\'/></body></html>";
  Map<String, String> rscIdMap = new HashMap<>(2);
  rscIdMap.put("pic1", ResourceUtils.getFile("classpath:pic01.jpg").getAbsolutePath());
  rscIdMap.put("pic2", ResourceUtils.getFile("classpath:pic02.jpg").getAbsolutePath());
  mailService.sendMimeMessge(TO, SUBJECT, htmlStr, rscIdMap);
 }
}