引入javamail的坐标依赖！省略！直接展示中心思想！

@Component

public class EmailUtil {

/**

* todo 发送QQ邮箱

*/

public void sendQQEmail(String emailAddress){

//做链接前的准备工作 也就是参数初始化

Properties properties = new Properties();

properties.setProperty("mail.smtp.host","smtp.qq.com");//发送邮箱服务器

properties.setProperty("mail.smtp.port","465");//发送端口

properties.setProperty("mail.smtp.auth","true");//是否开启权限控制

properties.setProperty("mail.debug","true");//true 打印信息到控制台

properties.setProperty("mail.transport","smtp");//发送的协议是简单的邮件传输协议

properties.setProperty("mail.smtp.ssl.enable","true");

//建立两点之间的链接

Session session = Session.getInstance(properties, new Authenticator() {

@Override

protected PasswordAuthentication getPasswordAuthentication() {

return new PasswordAuthentication("675361896@qq.com","wbomvmxtifjybcbb");

}

});

//创建邮件对象

Message message = new MimeMessage(session);

//设置发件人

try {

message.setFrom(new InternetAddress("675361896@qq.com"));

//设置收件人

message.setRecipient(Message.RecipientType.TO,new InternetAddress(emailAddress));//收件人

//设置主题

message.setSubject("Activiti工作流审核结果通知");

//设置邮件正文 第二个参数是邮件发送的类型

message.setContent("尊敬的用户您好，您的请假申请已通过，请知悉！","text/html;charset=UTF-8");

//发送一封邮件

Transport transport = session.getTransport();

transport.connect("675361896@qq.com","wbomvmxtifjybcbb");

Transport.send(message);

} catch (MessagingException e) {

e.printStackTrace();

}

}

/**

* todo 发送网易163邮箱

*/

// 发件人 账号和密码

public static final String MY_EMAIL_ACCOUNT = "fantongxue666@163.com";

public static final String MY_EMAIL_PASSWORD = "PCRAVAFQNZVIJDOI";// 密码,是你自己的设置的授权码

// SMTP服务器(这里用的163 SMTP服务器)

public static final String MEAIL_163_SMTP_HOST = "smtp.163.com";

public static final String SMTP_163_PORT = "25";// 端口号,这个是163使用到的;QQ的应该是465或者875

// 收件人

public static final String RECEIVE_EMAIL_ACCOUNT = "fantongxue666@163.com";

@Test

public void sendWY163Email(String emailAddress) throws Exception{

Properties p = new Properties();

p.setProperty("mail.smtp.host", MEAIL_163_SMTP_HOST);

p.setProperty("mail.smtp.port", SMTP_163_PORT);

p.setProperty("mail.smtp.socketFactory.port", SMTP_163_PORT);

p.setProperty("mail.smtp.auth", "true");

p.setProperty("mail.smtp.socketFactory.class", "SSL_FACTORY");

Session session = Session.getInstance(p, new Authenticator() {

// 设置认证账户信息

@Override

protected PasswordAuthentication getPasswordAuthentication() {

return new PasswordAuthentication(MY_EMAIL_ACCOUNT, MY_EMAIL_PASSWORD);

}

});

session.setDebug(true);

MimeMessage message = new MimeMessage(session);

// 发件人

message.setFrom(new InternetAddress(MY_EMAIL_ACCOUNT));

// 收件人和抄送人

message.setRecipients(Message.RecipientType.TO, RECEIVE_EMAIL_ACCOUNT);

//message.setRecipients(Message.RecipientType.CC, MY_EMAIL_ACCOUNT);

// 内容(这个内容还不能乱写,有可能会被SMTP拒绝掉;多试几次吧)

message.setSubject("Activiti工作流审核结果通知");

message.setContent("尊敬的用户您好，您的请假申请已通过，请知悉！", "text/html;charset=UTF-8");

message.setSentDate(new Date());

message.saveChanges();

Transport.send(message);

}

}

来源：https://www.cnblogs.com/fantongxue/p/12909690.html