邮件发送实例

@PostMapping("/sendEmail")
public Result sendEmail(String id, String toEmail, String ccEmail) {
    
    // 或 User obj = (User)session.getAttribute("currentUser");
    User user = (User) SecurityUtils.getSubject().getPrincipal();
    
    // TODO 获取信息
    
    MailBean mailBean = MailBean.getMailBean();
    Context context = new Context();
    context.setVariable("detail", detail);
    context.setVariable("user", user);
    
    // String template：模板页面，例如“template.html”
    String content = templateEngine.process(template, context);
    mailBean.setSubject("xxx");
    mailBean.setText(content);
    Result result = mailUtil.sendMailTemplate(mailBean, toEmail.replaceAll(" ", "").split(";"), ccEmail.replaceAll(" ", "").split(";"), null, null, user);
   
    // TODO 更改其他信息状态
   
    return result;
}

/**
 * 模板邮件发送
 * @param mailBean 邮件类
 * @param toEmails 收件人
 * @param ccEmails 抄送人
 * @param attachFiles 附件地址
 */
public Result sendMailTemplate(MailBean mailBean, String[] toEmails,String [] ccEmails, Map<String, String> attachFiles, Integer defaultFile, Map<String, String> inLine, User user) {
    try {
        setSMTPInfo(user);
        MimeMessage mimeMessage = mailSender.createMimeMessage();
        MimeMessageHelper helper = new MimeMessageHelper(mimeMessage, true);
        helper.setFrom(mailSender.getUsername());//发送者
        // 收件人设置默认
        if (null == toEmails || toEmails.length == 0){
            toEmails = new String[]{"xxx"};
        }
        helper.setTo(toEmails);//接收者
        if (null != ccEmails && ccEmails.length > 0) {
            helper.setCc(ccEmails);
        }
        helper.setSubject(mailBean.getSubject());//主题
        helper.setText(mailBean.getText(), true);//邮件内容
		if (null != attachFiles && !attachFiles.isEmpty()) {
            String uploadFileName;
            for (Map.Entry<String, String> filePath : attachFiles.entrySet()) {
                if (StringUtils.isNotBlank(filePath.getKey()) && StringUtils.isNotBlank(filePath.getValue())) {
                	// 通过远程文件链接添加附件
                    if (StringUtils.startsWith(filePath.getKey(),"http")){
                        uploadFileName = filePath.getKey();
                        // 链接内包含xxx地址，需要转成location资源地址，否则报错找不到地址
                        if (uploadFileName.contains("xxx")){ 
                            uploadFileName = "https"+ uploadFileName.substring(4);
                        }else {
                            // URLEncoder.encode(url.lastIndexOf("/") + 1), "UTF-8") 空格url编码是+号，404找不到链接地址
                            // UriUtils.encode 空格会url编码成%20
                            uploadFileName = uploadFileName.substring(0, uploadFileName.lastIndexOf("/") + 1) + UriUtils.encode(uploadFileName.substring(uploadFileName.lastIndexOf("/") + 1), "UTF-8");
                        }
                        URL fileUrl = new URL(uploadFileName);
                        HttpURLConnection urlCon = (HttpURLConnection) fileUrl.openConnection();
                        urlCon.setConnectTimeout(6000);
                        urlCon.setReadTimeout(6000);
                        int code = urlCon.getResponseCode();
                        if (code != HttpURLConnection.HTTP_OK) {
                            throw new Exception(filePath.getKey()+"文件读取失败");
                        }
                        InputStream in = urlCon.getInputStream();
                        helper.addAttachment(filePath.getValue(), new ByteArrayResource(IOUtils.toByteArray(in)));
                    }else { // 服务器本地文件添加附件
                        FileSystemResource file = new FileSystemResource(filePath.getKey());
                        helper.addAttachment(filePath.getValue(), file);
                    }
                }
            }
        }
		
        if (null != defaultFile && defaultFile < 0){
            FileSystemResource file = new FileSystemResource("C:\\template\\export.xls");
            helper.addAttachment("export.xls", file);
        }
        
        // 内联资源(静态资源)：邮件需要确保先设置邮件正文，再设置内联资源相关信息
        // 由于邮件服务商不同，可能有些邮件并不支持内联资源的展示；
        // 在测试过程中，新浪邮件不支持，QQ邮件支持；
        // 不支持不意味着邮件发送不成功，而且内联资源在邮箱内无法正确加载
        if (!inLine.isEmpty()) {
        	for (Map.Entry<String, String> inLinePath : inLine.entrySet()) {
        		FileSystemResource res = new FileSystemResource(new File(inLinePath.getKey());
            	helper.addInline(inLinePath.getValue(), res);
			}
        }
        mailSender.send(mimeMessage);
        return new Result(true);
    } catch (Exception e) {
        e.printStackTrace();
        log.error("邮件发送异常:"+e.getMessage(),e);
        return new Result(1,"mail failed to send,"+e.getMessage());
    }
}

签名中使用图片。内联资源的加载例子：

private void addInLineImages(MimeMessageHelper helper)
		throws MessagingException {
	ClassPathResource logoImage = new ClassPathResource(
			"template/email/imgs/logo.png");
	ClassPathResource barImage = new ClassPathResource(
			"template/email/imgs/code.png");
	helper.addInline("code", barImage, "image/x-png");
	helper.addInline("logo", logoImage, "image/x-png"); // <img src="cid:logo"/>
}