Springboot、EasyExcel 发送带附件的邮件

主要依赖

<dependency>
    <groupId>com.alibabagroupId>
    <artifactId>easyexcelartifactId>
    <version>2.2.11version>
dependency>

<dependency>
    <groupId>org.springframework.bootgroupId>
    <artifactId>spring-boot-starter-mailartifactId>
dependency>

<dependency>
    <groupId>org.projectlombokgroupId>
    <artifactId>lombokartifactId>
    <optional>trueoptional>
dependency>

配置

此处的协议为 smtps，且配置了各种超时时间，若超时时间不起作用，请移步 springboot java mail 超时配置不生效。

spring:
  mail:
    protocol: smtps
    host: smtp.mxhichina.com
    port: 465
    username: [email protected]
    password: xxxxxx
    properties:
      mail.smtps.connectiontimeout: 150000
      mail.smtps.timeout: 250000
      mail.smtps.writetimeout: 5000
      mail.smtp.auth: true
      mail.smtp.auth.starttls.required: true
      mail.smtp.auth.starttls.enable: true

代码

package com.example.mailexcel;

import com.alibaba.excel.EasyExcel;
import lombok.SneakyThrows;
import org.springframework.boot.autoconfigure.mail.MailProperties;
import org.springframework.core.io.ByteArrayResource;
import org.springframework.mail.javamail.JavaMailSender;
import org.springframework.mail.javamail.MimeMessageHelper;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import javax.mail.internet.MimeMessage;
import java.io.ByteArrayOutputStream;
import java.util.ArrayList;
import java.util.List;

@RestController
@RequestMapping("/mail")
public class MailController {

    private final JavaMailSender javaMailSender;

    private final MailProperties mailProperties;

    public MailController(JavaMailSender javaMailSender, 
                          MailProperties mailProperties) {
        this.javaMailSender = javaMailSender;
        this.mailProperties = mailProperties;
    }

    @PostMapping("/send")
    public String send() {
        byte[] bytes = excelToByteArray(data());
        email(bytes);
        return "OK";
    }

    @SneakyThrows
    private void email(byte[] attachment) {
        MimeMessage message = javaMailSender.createMimeMessage();
        MimeMessageHelper helper = new MimeMessageHelper(message, true);
        helper.setFrom(mailProperties.getUsername());
        helper.setTo("[email protected]");
        helper.setText("内容：测试");
        helper.setSubject("主题：测试");
        // 附件
        helper.addAttachment("测试.xlsx", new ByteArrayResource(attachment));
        javaMailSender.send(message);
    }

    /**
     * 将 Excel 写入 ByteArrayOutputStream
     */
    private byte[] excelToByteArray(List<User> list) {
        ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
        EasyExcel.write(outputStream, User.class).sheet("测试").doWrite(list);
        return outputStream.toByteArray();
    }

    /**
     * 数据
     */
    public static List<User> data() {
        List<User> list = new ArrayList<>();
        list.add(new User(1, "小明", 18));
        list.add(new User(2, "小红", 20));
        list.add(new User(3, "小华", 25));
        return list;
    }
}