Java通过Jakarta Mail实现邮件发送

问题描述

需要实现邮件发送的功能，对过程进行一下记录。

步骤

① 首先需要开启邮箱的smtp服务，现在很多邮箱默认关闭smtp，pop3，imap服务，需要登录邮箱后在设置中手动开启。

② 引入Jakarta Mail依赖包

	org.springframework.boot
	spring-boot-starter-mail

③ 邮件信息对象

package com.changkong.util.email;

import com.sun.mail.util.MailSSLSocketFactory;
import java.security.GeneralSecurityException;
import java.util.List;
import java.util.Properties;
import lombok.Data;

@Data
public class MailSenderInfo {
    // 发送邮件的服务器的IP和端口
    private String mailServerHost;
    private String mailServerPort = "465";
    private boolean enableSSL;
    private boolean enableTLS;
    // 邮件发送者的地址
    private String fromAddress;
    // 邮件接收者的地址
    private List toAddressList;
    // 登陆邮件发送服务器的用户名和密码
    private String userName;
    private String password;
    // 是否需要身份验证
    private boolean validate = false;
    // 邮件主题
    private String subject;
    // 邮件的文本内容
    private String content;
    // 邮件附件的文件名
    private List attachFileNames;

    /**
     * 获得邮件会话属性
     */
    public Properties getProperties() throws GeneralSecurityException {
        Properties p = new Properties();
        p.put("mail.smtp.host", this.mailServerHost);
        p.put("mail.smtp.port", this.mailServerPort);
        if (this.enableSSL) {
            MailSSLSocketFactory sf = null;
            sf = new MailSSLSocketFactory();
            // 设置信任所有的主机
            sf.setTrustAllHosts(true);
            p.put("mail.smtp.ssl.enable", "true");
            p.put("mail.smtp.ssl.socketFactory", sf);
        }
        p.put("mail.smtp.starttls.enable", enableTLS ? "true" : false);
        p.put("mail.smtp.auth", validate ? "true" : "false");
        return p;
    }
}

④ 认证对象

package com.changkong.util.email;

import jakarta.mail.Authenticator;
import jakarta.mail.PasswordAuthentication;

public class MyAuthenticator extends Authenticator {
    private String userName;
    private String password;

    public MyAuthenticator() {
    }

    public MyAuthenticator(String userName, String password) {
        this.userName = userName;
        this.password = password;
    }

    @Override
    protected PasswordAuthentication getPasswordAuthentication() {
        return new PasswordAuthentication(userName, password);
    }
}

⑤ 邮件发送工具类

package com.changkong.util.email;

import jakarta.activation.DataHandler;
import jakarta.activation.FileDataSource;
import jakarta.mail.*;
import jakarta.mail.internet.*;
import java.util.Date;
import java.util.Properties;

public class Email {
    /**
     * 以文本格式发送邮件
     *
     * @param mailInfo 待发送邮件信息
     * @throws Exception
     */
    public static void sendTextMail(MailSenderInfo mailInfo) throws Exception {
        mailInfo.setSubject("测试邮件");
        MimeMessage mailMessage = initMimeMessage(mailInfo);
        // 设置邮件消息的主要内容
        String mailContent = mailInfo.getContent();
        mailMessage.setText(mailContent);
        if (mailInfo.getAttachFileNames() != null) {
            MimeMultipart multipart = new MimeMultipart();
            for (String fileName : mailInfo.getAttachFileNames()) {
                MimeBodyPart attachment = new MimeBodyPart();
                // 读取本地文件
                DataHandler dh2 = new DataHandler(new FileDataSource(fileName));
                // 将附件数据添加到"节点"
                attachment.setDataHandler(dh2);
                // 设置附件的文件名（需要编码）
                attachment.setFileName(MimeUtility.encodeText(dh2.getName()));
                // 10. 设置（文本+图片）和 附件 的关系（合成一个大的混合"节点" / Multipart ）
                MimeMultipart mm = new MimeMultipart();
                mm.addBodyPart(attachment);     // 如果有多个附件，可以创建多个多次添加
                mm.setSubType("mixed");         // 混合关系
                multipart.addBodyPart(attachment);
            }
            mailMessage.setContent(multipart);
        }
        // 发送邮件
        Transport.send(mailMessage);
    }

    /**
     * 以HTML格式发送邮件
     *
     * @param mailInfo 待发送邮件信息
     * @throws Exception
     */
    public static void sendHtmlMail(MailSenderInfo mailInfo) throws Exception {
        MimeMessage mailMessage = initMimeMessage(mailInfo);
        Multipart multipart = new MimeMultipart();
        if (mailInfo.getAttachFileNames() != null) {
            for (String fileName : mailInfo.getAttachFileNames()) {
                MimeBodyPart attachment = new MimeBodyPart();
                // 读取本地文件
                DataHandler dh2 = new DataHandler(new FileDataSource(fileName));
                // 将附件数据添加到"节点"
                attachment.setDataHandler(dh2);
                // 设置附件的文件名（需要编码）
                attachment.setFileName(MimeUtility.encodeText(dh2.getName()));
                // 10. 设置（文本+图片）和 附件 的关系（合成一个大的混合"节点" / Multipart ）
                MimeMultipart mm = new MimeMultipart();
                mm.addBodyPart(attachment);     // 如果有多个附件，可以创建多个多次添加
                mm.setSubType("mixed");         // 混合关系
                multipart.addBodyPart(attachment);
            }
            mailMessage.setContent(multipart);
        }
        // 创建一个包含HTML内容的MimeBodyPart
        BodyPart html = new MimeBodyPart();
        html.setContent(mailInfo.getContent(), "text/html; charset=utf-8");
        multipart.addBodyPart(html);
        // 将MiniMultipart对象设置为邮件内容
        mailMessage.setContent(multipart);
        // 发送邮件
        Transport.send(mailMessage);
    }

    private static MimeMessage initMimeMessage(MailSenderInfo mailInfo) throws Exception {
        // 判断是否需要身份认证
        MyAuthenticator authenticator = null;
        Properties pro = mailInfo.getProperties();
        if (mailInfo.isValidate()) {
            // 如果需要身份认证，则创建一个密码验证器
            authenticator = new MyAuthenticator(mailInfo.getUserName(), mailInfo.getPassword());
        }
        // 根据邮件会话属性和密码验证器构造一个发送邮件的session
        Session sendMailSession = Session.getDefaultInstance(pro, authenticator);
        // 根据session创建一个邮件消息
        MimeMessage mailMessage = new MimeMessage(sendMailSession);
        // 创建邮件发送者地址
        Address from = new InternetAddress(mailInfo.getFromAddress());
        // 设置邮件消息的发送者
        mailMessage.setFrom(from);
        // 创建邮件的接收者地址，并设置到邮件消息中
        InternetAddress[] receiverAddress = new InternetAddress[mailInfo.getToAddressList().size()];
        for (int i = 0; i < mailInfo.getToAddressList().size(); i++) {
            receiverAddress[i] = new InternetAddress(mailInfo.getToAddressList().get(i));
        }
        mailMessage.setRecipients(Message.RecipientType.TO, receiverAddress);
        // 设置邮件消息的主题
        mailMessage.setSubject(mailInfo.getSubject());
        // 设置邮件消息发送的时间
        mailMessage.setSentDate(new Date());
        return mailMessage;
    }
}

⑥ 验证邮件发送

	//测试方法
    public static void main(String[] args){
        MailSenderInfo mailSenderInfo = new MailSenderInfo();
        mailSenderInfo.setMailServerHost("smtp.163.com");
        mailSenderInfo.setFromAddress("[email protected]");
        mailSenderInfo.setValidate(true);
        mailSenderInfo.setUserName("[email protected]");
        mailSenderInfo.setPassword("XXXXXXXXXX");
        List toAddressList = new ArrayList<>();
        toAddressList.add("[email protected]");
        mailSenderInfo.setToAddressList(toAddressList);
        mailSenderInfo.setSubject("测试邮件");
        mailSenderInfo.setContent("测试测试测试测试测试...");
        mailSenderInfo.setAttachFileNames(Arrays.asList("C:\\Users\\changkong\\Desktop\\test.sql"));
        try {
            Email.sendTextMail(mailSenderInfo);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }