邮件html内容中带内网图片地址发送

左手的ㄟ右手 2023-10-11 12:00 27阅读 0赞

**直接使用图片的局域网地址(此方案不可行)**

直接使用图片的局域网内的地址，比如图片url地址为本地地址，则只有在本机上打开收到的邮件时才会显示图片，在其他机器上打开邮件发现图片不显示

解决方案：  
1.为图片存储的环境映射外网地址  
2.使用javamail提供的cid方式进行图片发送（可行）

# 使用javamail中cid方式发送html中的图片 #

1 package com.montnets.test;
      2 
      3 import com.montnets.email.specmailgate.constant.EmailGateConstant;
      4 import com.montnets.email.specmailgate.service.MyAuthenticator;
      5 import lombok.extern.slf4j.Slf4j;
      6 import org.dom4j.Document;
      7 import org.dom4j.DocumentHelper;
      8 import org.dom4j.Element;
      9 
     10 import javax.activation.DataHandler;
     11 import javax.mail.Message;
     12 import javax.mail.MessagingException;
     13 import javax.mail.Session;
     14 import javax.mail.Transport;
     15 import javax.mail.internet.InternetAddress;
     16 import javax.mail.internet.MimeBodyPart;
     17 import javax.mail.internet.MimeMessage;
     18 import javax.mail.internet.MimeMultipart;
     19 import java.net.HttpURLConnection;
     20 import java.net.URL;
     21 import java.util.*;
     22 
     23 /**
     24  * @Author: chenlinyan
     25  * @Date: 2019/7/8 16:40
     26  * @Version 1.0
     27  */
     28 @Slf4j
     29 public class TestEmail {
     30 
     31 
     32     /**
     33      * 创建一封邮件的实例对象
     34      *
     35      * @param session
     36      * @param theme 邮件主题
     37      * @param content 邮件内容
     38      * @param sendAccount 发送账号
     39      * @param receiver 接收者账号
     40      * @return
     41      * @throws Exception
     42      */
     43     public MimeMessage getMimeMessage(Session session, String theme, String content, String sendAccount, String receiver) throws Exception {
     44         //创建一封邮件的实例对象
     45         MimeMessage msg = new MimeMessage(session);
     46         //设置发件人地址
     47         msg.setFrom(new InternetAddress(sendAccount));
     48         //单个目标收件人
     49         msg.setRecipient(MimeMessage.RecipientType.TO, new InternetAddress(receiver));
     50         //设置邮件主题
     51         msg.setSubject(theme);
     52         MimeMultipart multipart = new MimeMultipart();
     53         //处理邮件内容
     54         Document document = getHtmlDocument(content);
     55         if (document != null) {
     56             Set<String> imgPaths = getImgs(document);
     57             setImageMultipart(multipart, imgPaths);
     58             content = getHtmlContent(document);
     59         }
     60         //设置邮件正文
     61         MimeBodyPart text = new MimeBodyPart();
     62         text.setContent(content, "text/html;charset=UTF-8");
     63         multipart.addBodyPart(text);
     64         multipart.setSubType("related");
     65         msg.setSentDate(new Date());
     66         msg.setContent(multipart);
     67         msg.saveChanges();
     68         return msg;
     69     }
     70 
     71 
     72     public Document getHtmlDocument(String html) {
     73         try {
     74              //有些图片链接带有&符号
     75             String content = html.replace("&", "&");
     76             return DocumentHelper.parseText(content);
     77         } catch (Exception e) {
     78             log.warn("邮件html内容不符合xml格式，邮件内容为{}", html, e);
     79             return null;
     80         }
     81     }
     82 
     83 
     84     public String getHtmlContent(Document document) {
     85         String content = document.asXML().replace("&", "&");
     86         log.info("邮件发送内容为:{}", content);
     87         return content;
     88     }
     89 
     90     /**
     91      * 获取图片资源地址
     92      *
     93      * @param document
     94      * @return
     95      */
     96     public Set<String> getImgs(Document document) {
     97         Set<String> sets = new HashSet<>();
     98         String imgPath = null;
     99         try {
    100             List<Element> elements = document.selectNodes("//img");
    101             for (Element element : elements) {
    102                 imgPath = element.attributeValue("src");
    103                 if (imgPath != null) {
    104                     element.addAttribute("src", "cid:" + imgPath);
    105                     sets.add(imgPath);
    106                 }
    107             }
    108         } catch (Exception e) {
    109             log.error("获取html中img标签内图片路径异常,html内容为{}", document.asXML(), e);
    110         }
    111         return sets;
    112     }
    113 
    114 
    115     /**
    116      * 设置图片cid至MimeMultipart中
    117      *
    118      * @param multipart
    119      * @param imgPaths
    120      */
    121     public void setImageMultipart(MimeMultipart multipart, Set<String> imgPaths) {
    122         if (imgPaths == null || imgPaths.isEmpty()) {
    123             return;
    124         }
    125         MimeBodyPart image = null;
    126         URL url;
    127         for (String imgPath : imgPaths) {
    128             try {
    129                 url = new URL(imgPath);
    130                 //判断图片地址资源是否可访问
    131                 if (isConnect(url)) {
    132                     image = new MimeBodyPart();
    133                     DataHandler dh = new DataHandler(url);
    134                     image.setDataHandler(dh);
    135                     image.setContentID(imgPath);
    136                     multipart.addBodyPart(image);
    137                 } else {
    138                     log.warn("{}资源地址无效", imgPath);
    139                 }
    140             } catch (Exception e) {
    141                 log.error("邮件图片发送，设置图片cid异常，异常图片为{}", imgPath, e);
    142             }
    143         }
    144     }
    145 
    146 
    147     /**
    148      * 功能：检测当前URL是否可连接或是否有效,
    149      * 描述：最多连接网络 n 次, 如果 n 次都不成功，视为该地址不可用
    150      *
    151      * @param url 指定URL网络地址
    152      * @return boolean
    153      */
    154     public synchronized static boolean isConnect(URL url) {
    155         HttpURLConnection con;
    156         int state = -1;
    157         int counts = 0;
    158         if (url == null) {
    159             return false;
    160         }
    161         while (counts < EmailGateConstant.CONN_TIMES) {
    162             try {
    163                 con = (HttpURLConnection) url.openConnection();
    164                 //连接超时时间
    165                 con.setConnectTimeout(3000);
    166                 state = con.getResponseCode();
    167                 if (state == 200) {
    168                     return true;
    169                 }
    170                 break;
    171             } catch (Exception ex) {
    172                 counts++;
    173                 continue;
    174             }
    175         }
    176         return false;
    177     }
    178 
    179 
    180     /**
    181     *方法入口，测试
    182     */
    183     public static void main(String[] args) {
    184         String host = "smtp.qq.com";
    185         String sendAccount = "xxxx@qq.com";
    186         String receiver = "xxxx@qq.com";
    187         String pwd = "123456";
    188         String theme = "发送图片";
    189         String content = "<p>图片测试<img src=\"http://192.169.1.101:8080/WebTest/file/qq.PNG\"/></p>";
    190 
    191         Properties props = new Properties();
    192         //设置用户的认证方式
    193         props.setProperty("mail.smtp.auth", "true");
    194         //设置传输协议
    195         props.setProperty("mail.transport.protocol", "smtp");
    196         //设置发件人的SMTP服务器地址
    197         props.setProperty("mail.smtp.host", host);
    198         props.setProperty("mail.smtp.port", "25");
    199         //连接超时时间
    200         props.put("mail.smtp.connectiontimeout", 30000);
    201         //读超时时间
    202         props.put("mail.smtp.timeout", 30000);
    203         //写超时时间
    204         props.put("mail.smtp.writetimeout", 30000);
    205 
    206         Transport transport = null;
    207         try {
    208             //1、创建定义整个应用程序所需的环境信息的 Session 对象
    209             Session session = Session.getInstance(props, new MyAuthenticator(sendAccount, pwd));
    210             //设置调试信息在控制台打印出来
    211             session.setDebug(true);
    212             //根据session对象获取邮件传输对象Transport
    213             transport = session.getTransport();
    214 //        //添加监听器
    215 //        transport.addTransportListener(mailListener);
    216             //与服务器建立连接
    217             transport.connect();
    218             Message message = new TestEmail().getMimeMessage(session, theme,content,sendAccount,receiver);
    219             //发送邮件
    220             transport.sendMessage(message, message.getAllRecipients());
    221         } catch (Exception e) {
    222             e.printStackTrace();
    223         }finally {
    224             if(transport != null){
    225                 try {
    226                     transport.close();
    227                 } catch (MessagingException e) {
    228                     e.printStackTrace();
    229                 }
    230             }
    231         }
    232     }
    233 }

转载于:https://www.cnblogs.com/kiko2014551511/p/11525558.html