自己的授权码自己记好
引入依赖

<dependency>
   <groupId>com.sun.mail</groupId>
    <artifactId>javax.mail</artifactId>
    <version>1.6.2</version>
</dependency>
<dependency>
    <groupId>javax.mail</groupId>
    <artifactId>javax.mail-api</artifactId>
    <version>1.4.7</version>
</dependency>

controller层代码

package com.cao.controller;

import com.cao.pojo.Mail;
import com.cao.utils.EmailUtils;
import com.google.gson.Gson;
import lombok.extern.slf4j.Slf4j;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

@RestController
@RequestMapping("/api/email")
@Slf4j
public class SendEmailController {

    @PostMapping("/send") // http://localhost:8080/api/email/send
    public String sendEmail(@RequestBody Mail mail) {
        Gson gson = new Gson();
        log.info("输入的mail对象是: {}", gson.toJson(mail));
        try {
            EmailUtils.createMimeMessage(mail.getSendEmail(),
                    mail.getReceiveEmail(),
                    mail.getReceiveName(),
                    mail.getSubject(),
                    mail.getSendName(),
                    mail.getContent());
            return "发送完成";
        } catch (Exception e) {
            log.error("发送出现了异常", e);
            throw new RuntimeException(e);
        }
    }
}

Service层代码

package com.cao.utils;

import javax.mail.Session;
import javax.mail.Transport;
import javax.mail.internet.InternetAddress;
import javax.mail.internet.MimeMessage;
import java.util.Date;
import java.util.Properties;

public class EmailUtils {
    /**
     * 发件⼈邮箱密码 - 登录邮件开启 SMTP 服务后，邮件服务商⽣成的“授权码”
     */
    public static final String authorizeCode = "oeqdschg1122lhgecbe12";  //自己的授权码替换下

    /**
     * 发件⼈SMTP服务器地址，⼀般的格式为：smtp.xxx.com，其中xxx为邮件服务商名称
     */
    public static final String smtpHost = "smtp.qq.com";

    /**
     * 协议
     */
    public static final String protocol = "smtp";

    public static Session getEmailSession() {
        // 参数配置，⽤于连接邮件服务器
        Properties props = new Properties();
        // 使⽤协议
        props.setProperty("mail.transport.protocol", protocol);
        // 发件⼈邮箱的 SMTP 服务器地址
        props.setProperty("mail.smtp.host", smtpHost);
        // 需要请求认证
        props.setProperty("mail.smtp.auth", "true");
        // 创建会话对象，⽤于与邮箱服务器交互
        Session session = Session.getInstance(props);
        // 设置为debug模式，在控制台中可以查看详细的发送⽇志
        session.setDebug(true);
        return session;
    }

    /**
     * 发送邮件的工具类
     */
    public static MimeMessage createMimeMessage(String sendEmail, String receiveEmail, String receiveName, String subject, String sendName, String content) throws Exception {
        Session session = getEmailSession();
        // 1.创建邮件对象
        MimeMessage message = new MimeMessage(session);
        // 2.设置发件⼈，其中 InternetAddress 有三个参数，分别为：邮箱，显示的昵称，昵称的字符集编码
        message.setFrom(new InternetAddress(sendEmail, sendName, "UTF-8"));
        // 3.设置收件⼈ - MimeMessage.RecipientType.TO
        message.setRecipient(MimeMessage.RecipientType.TO, new InternetAddress(receiveEmail, receiveName, "UTF-8"));
        // 4.设置邮件主题
        message.setSubject(subject, "UTF-8");
        // 5.设置邮件正⽂内容，指定格式为HTML格式
        message.setContent(content, "text/html;charset=UTF-8");
        // 6.设置显示发件时间
        message.setSentDate(new Date());
        // 7.保存设置
        message.saveChanges();
        // 8.根据 Session 获取邮件传输对象
        Transport transport = session.getTransport();
        // 9.连接邮件服务器
        transport.connect(sendEmail, authorizeCode);
        // 10.发送邮件
        transport.sendMessage(message, message.getAllRecipients());
        // 11.关闭连接
        transport.close();
        return message;
    }
}

测试： 调用controller


查看是否有邮件收到