问答平台（2），发送邮件

邮箱设置

- 启动客户端SMTP服务

示意图

---

Spring Email

• 导入jar包

  <dependency>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-starter-mail</artifactId>
      <version>2.1.5.RELEASE</version>
  </dependency>

• 邮箱参数配置

  # MailProperties
  spring.mail.host=smtp.sina.com
  spring.mail.port=465
  spring.mail.username=liming163vip@sina.com
  spring.mail.password=xxx...
  spring.mail.protocol=smtps
  spring.mail.properties.mail.smtp.ssl.enable=true

• JavaMailSender 发送邮件

  // JavaMailSender.java
  public interface JavaMailSender extends MailSender {
      MimeMessage createMimeMessage();
  
      MimeMessage createMimeMessage(InputStream var1) throws MailException;
  
      void send(MimeMessage var1) throws MailException;
  
      void send(MimeMessage... var1) throws MailException;
  
      void send(MimeMessagePreparator var1) throws MailException;
  
      void send(MimeMessagePreparator... var1) throws MailException;
  }

---

工具类

// MailClient.java
@Component
public class MailClient {

    private static final Logger logger = LoggerFactory.getLogger(MailClient.class);

    @Autowired
    private JavaMailSender mailSender;

    @Value("${spring.mail.username}")
    private String from;

    public void sendMail(String to, String subject, String content) {
        try {
            // 通过createMimeMessage()对象构建一个模版，还需要往里面填充内容
            MimeMessage message = mailSender.createMimeMessage();

            // MimeMessageHelper对象填充邮件内容
            MimeMessageHelper helper = new MimeMessageHelper(message);
            helper.setFrom(from);
            helper.setTo(to);
            helper.setSubject(subject);
            helper.setText(content, true);

            // 发送邮件
            mailSender.send(helper.getMimeMessage());
        } catch (MessagingException e) {
            logger.error("发送邮件失败:" + e.getMessage());
        }
    }
}

---

模板引擎

• 使用Thymeleaf发送HTML邮件，里面有动态参数

  <p>欢迎你，<span style="color:red;" th:text="${username}"></span>!</p>

---

测试类

// MailTests.java
@RunWith(SpringRunner.class)
@SpringBootTest
@ContextConfiguration(classes = CommunityApplication.class)
public class MailTests {

    @Autowired
    private MailClient mailClient;

    @Autowired
    private TemplateEngine templateEngine;

    @Test
    public void testTextMail() {
        mailClient.sendMail("liming163vip@163.com", "Test", "Welcome");
    }

    @Test
    public void testHtmlMail() {
        // 构建参数,传入网页
        Context context = new Context();
        context.setVariable("username", "Saturday");

        // 调用模版引擎
        String content = templateEngine.process("/mail/demo", context);
        System.out.println(content);

        // 发送邮件,将HTML作为内容
        mailClient.sendMail("liming163vip@163.com", "HTML", content);
    }
}