Java配置邮箱服务发送邮件

1. 申请邮箱服务开通POP3/SMTP（以qq邮箱为例）
   
   直接在这里生成授权码
2. 记住开通的邮箱账号和授权码，在java里面配置
3. Java程序

private Boolean sendEmail(String toEmail, String subject, String content){
        try {
            // 发件人电子邮箱
            String from = ""; 
            // 指定发送邮件的主机
            String host = "";
            // 指定发送邮件端口，默认25
            String port = "25";
            //授权码或密码，刚在qq邮箱里面生成的授权码
            String authorizationCode = ”“;
            // 获取系统属性
            Properties properties = System.getProperties();
            // 设置邮件服务器
            properties.setProperty("mail.smtp.host", host);
            // 打开认证
            properties.setProperty("mail.smtp.auth", "true");
            properties.setProperty("mail.smtp.port", port);
            properties.put("mail.smtp.starttls.enable", "true");

            Session session = Session.getInstance(properties, new Authenticator() {
                @Override
                protected PasswordAuthentication getPasswordAuthentication() {
                    return new PasswordAuthentication(from, authorizationCode);
                }
            });
            Message message = new MimeMessage(session);
            message.setFrom(new InternetAddress(from));
            message.setRecipient(Message.RecipientType.TO, new InternetAddress(toEmail));

            message.setSubject(subject);
            message.setContent(content, "text/html;charset=utf-8");
            Transport.send(message);
            return true;
        } catch (MessagingException e) {
            log.error("邮件发送异常", e);
            return false;
        }
    }