如何在Spring Boot应用中使用Freemarker模板发送电子邮件？

在Spring Boot应用中使用Freemarker模板发送电子邮件可以通过以下步骤实现：

添加依赖：在pom.xml文件中添加spring-boot-starter-mail和spring-boot-starter-freemarker依赖。

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

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

配置邮件发送参数：在application.properties或application.yml文件中配置邮件发送的相关参数。

spring.mail.host=smtp.example.com
spring.mail.port=587
spring.mail.username=your-email@example.com
spring.mail.password=your-password
spring.mail.properties.mail.smtp.auth=true
spring.mail.properties.mail.smtp.starttls.enable=true

创建邮件模板：在src/main/resources/templates目录下创建邮件模板，例如email-template.ftl。

<!DOCTYPE html>
<html>
<head>
    <title>Spring Boot Email Example</title>
</head>
<body>
    <h1>Hello ${name}!</h1>
    <p>This is a sample email template.</p>
</body>
</html>

创建邮件发送服务：创建一个类，用于实现邮件发送的逻辑。

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.mail.SimpleMailMessage;
import org.springframework.mail.javamail.JavaMailSender;
import org.springframework.mail.javamail.MimeMessageHelper;
import org.springframework.stereotype.Service;
import org.springframework.ui.freemarker.FreeMarkerTemplateUtils;
import freemarker.template.Configuration;
import freemarker.template.Template;

@Service
public class EmailService {

    @Autowired
    private JavaMailSender mailSender;

    @Autowired
    private Configuration freemarkerConfig;

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

    public void sendEmail(String to, String subject, String templateName, Object model) throws Exception {
        MimeMessage message = mailSender.createMimeMessage();
        MimeMessageHelper helper = new MimeMessageHelper(message, true);

        helper.setFrom(from);
        helper.setTo(to);
        helper.setSubject(subject);

        Template template = freemarkerConfig.getTemplate(templateName);
        String content = FreeMarkerTemplateUtils.processTemplateIntoString(template, model);

        helper.setText(content, true);

        mailSender.send(message);
    }
}

使用邮件发送服务：在需要发送邮件的地方调用邮件发送服务。

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.RequestMapping;

@Controller
public class EmailController {

    @Autowired
    private EmailService emailService;

    @RequestMapping("/sendEmail")
    public String sendEmail(Model model) {
        String to = "recipient@example.com";
        String subject = "Test Email";
        String templateName = "email-template.ftl";

        model.addAttribute("name", "Recipient Name");

        try {
            emailService.sendEmail(to, subject, templateName, model);
            return "Email sent successfully!";
        } catch (Exception e) {
            return "Email sending failed!";
        }
    }
}

以上就是在Spring Boot应用中使用Freemarker模板发送电子邮件的步骤。你可以根据实际需求修改模板和发送逻辑。对于电子邮件的发送和模板的使用，Spring Boot提供了方便的封装和集成，使得开发变得更加简单和高效。

推荐的腾讯云相关产品：腾讯云的邮件推送服务（https://cloud.tencent.com/product/tws）可以用于在云平台上发送电子邮件，具有高可用性、低延迟和高成功率的特点。