问题:
如何用java发送包含表格形式的邮件?
方法:
发用freemaker工具来替换html的表格变量,从而动态生成了html。然后再发送这个html格式(不能用纯文本)文本即可。
优化流程:
1、准备模板(这里是以Excel转html为模板)
2、处理模板及对模板填充内容的工具类
3、修改发送邮件的代码
所需依赖
pom.xml依赖
<!-- freemarker -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-freemarker</artifactId>
</dependency>
<dependency>
<groupId>cn.hutool</groupId>
<artifactId>hutool-all</artifactId>
<version>5.8.4</version>
</dependency>
具体实现
1、准备模板
先用excel画一个模板,如下图
然后在网上找一个excel转换html的在线转换工具
我用的是:零代码 - Table在线布局工具(Excel转HTML)
2. 转换成功之后下载,之后会得到这样一个html文件。
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>www.lingdaima.com(零代码excel转HTML)</title>
<style>
table{border-top:1px solid #333;border-left:1px solid #333;border-spacing:0;background-color:#fff;width:100%}
table td{border-bottom:1px solid #333;border-right:1px solid #333;font-size:13px;padding:5px}
.font5{color:windowtext;}
.xl65{text-align:left ;}
</style>
</head>
<body>
<table style="width:500pt"> <!--StartFragment-->
<colgroup>
<col width="111" style="mso-width-source:userset;mso-width-alt:3552;width:83pt">
<col width="131" style="mso-width-source:userset;mso-width-alt:4192;width:98pt">
<col width="290" style="mso-width-source:userset;mso-width-alt:9280;width:218pt">
<col width="135" style="mso-width-source:userset;mso-width-alt:4320;width:101pt">
</colgroup>
<tbody>
<tr height="19">
<td class="xl65">号码</td>
<td class="xl65">所属运营商</td>
<td class="xl65">所属号码组</td>
<td class="xl65">报警时间</td>
</tr>
<tr height="19">
<td class="xl65">15528474394</td>
<td class="xl65">万事融通</td>
<td class="xl65">智慧外呼_万事融通_日产专用_品牌认证</td>
<td class="xl65">2024/10/24 9:35</td>
</tr> <!--EndFragment-->
</tbody>
</table>
</body>
</html>
3.把这个文件修改为 alert-email-template.ftl, 放到 java 项目的 resouce/ftl/目录下
该文件的内容为
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<style>
table{border-top:1px solid #333;border-left:1px solid #333;border-spacing:0;background-color:#fff;width:100%}
table td{border-bottom:1px solid #333;border-right:1px solid #333;font-size:13px;padding:5px}
.font5{color:windowtext;}
.xl65{text-align:left ;}
</style>
</head>
<body>
<div style="font-size: 12px; margin: 10px;">
您好:<br/>
      本次共有${totalAmounts}个未接通号码,详情请参见附件。
<br/>
下面列出的是前${topAmounts}个未接通号码详细信息。
<br/>
</div>
<table style="width:500pt"> <!--StartFragment-->
<colgroup>
<col width="111" style="mso-width-source:userset;mso-width-alt:3552;width:83pt">
<col width="131" style="mso-width-source:userset;mso-width-alt:4192;width:98pt">
<col width="290" style="mso-width-source:userset;mso-width-alt:9280;width:218pt">
<col width="135" style="mso-width-source:userset;mso-width-alt:4320;width:101pt">
</colgroup>
<tbody>
<tr height="19">
<td class="xl65">号码</td>
<td class="xl65">所属运营商</td>
<td class="xl65">所属号码组</td>
<td class="xl65">报警时间</td>
</tr>
<#if items?? && (items? size >0)>
<#list items as item>
<tr height="18">
<td class="xl66">${(item.phone)!}</td>
<td class="xl66">${(item.supplier)!}</td>
<td class="xl66">${(item.group)!}</td>
<td class="xl66">${(item.time)!}</td>
</tr>
</#list>
</#if>
</tbody>
</table>
</body>
</html>
这里带$的就是需要freemaker来替换的变量。
注:这里items是一个list变量。
- 处理模板及对模板填充内容的工具类
直接上java代码
@Data
public class FailedCallInfo {
private String phone;
private String supplier;
private String group;
private String time;
}
List<FailedCallInfo> items = new ArrayList<>();
FailedCallInfo record = new FailedCallInfo();
record.setPhone("123456");
record.setSupplier("abc");
record.setGroup("group1");
record.setTime("2024-10-10 12:12:00");
items.add(record);
Map<String, Object> callInfoMap = new HashMap<>(32);
//注意变量名字要和ftl模板里面的一致!
callInfoMap.put("items", items);
callInfoMap.put("totalAmounts", 1);
callInfoMap.put("topAmounts", 1);
String generatedEmailBodyText = null;
try {
generatedEmailBodyText = FreemarkerUtil.generate("alert-email-template.ftl", callInfoMap);
} catch (IOException e) {
log.warn("email template generation failed, IOException exception:{}", e.getMessage());
csvfile.delete();
return;
} catch (TemplateException e) {
log.warn("email template generation failed, TemplateException exception:{}", e.getMessage());
csvfile.delete();
return;
}
boolean send_result = EmailHelper.send(receivers, null, null, "未接通号码告警邮件", generatedEmailBodyText, attachment, "xc-jsb-sjjg-unit@autohome.com.cn");
if (send_result) {
log.info("发送告警邮件成功!收件人:{}", JSON.toJSONString(receivers));
} else {
log.warn("发送告警邮件失败,收件人:{}", JSON.toJSONString(receivers));
}
FreemarkerUtil.java
package com.xxx.util;
import freemarker.template.Configuration;
import freemarker.template.Template;
import freemarker.template.TemplateException;
import java.io.BufferedWriter;
import java.io.IOException;
import java.io.StringWriter;
/**
* freemarker 工具类
*/
public class FreemarkerUtil {
private static Configuration config = null;
/**
* Static initialization.
*
* Initialize the configuration of Freemarker.
*/
static {
config = new Configuration();
config.setClassForTemplateLoading(FreemarkerUtil.class, "/ftl/");
config.setTemplateUpdateDelay(0);
}
public static Configuration getConfiguration() {
return config;
}
/**
* @param template
* @return
* @throws Exception
*/
public static String generate(String template, Object obj) throws IOException, TemplateException {
Configuration config = getConfiguration();
config.setDefaultEncoding("UTF-8");
Template tp = config.getTemplate(template, "utf-8");
StringWriter stringWriter = new StringWriter();
BufferedWriter writer = new BufferedWriter(stringWriter);
tp.setEncoding("UTF-8");
tp.process(obj, writer);
String htmlStr = stringWriter.toString();
writer.flush();
writer.close();
return htmlStr;
}
}
EmailHelper.java
package com.xxx.util;
import java.io.File;
import java.util.ArrayList;
import java.util.List;
import java.util.Properties;
import javax.activation.DataHandler;
import javax.activation.DataSource;
import javax.activation.FileDataSource;
import javax.mail.Authenticator;
import javax.mail.Message;
import javax.mail.MessagingException;
import javax.mail.Multipart;
import javax.mail.PasswordAuthentication;
import javax.mail.Session;
import javax.mail.Transport;
import javax.mail.internet.AddressException;
import javax.mail.internet.InternetAddress;
import javax.mail.internet.MimeBodyPart;
import javax.mail.internet.MimeMessage;
import javax.mail.internet.MimeMultipart;
import javax.mail.internet.MimeUtility;
import lombok.extern.slf4j.Slf4j;
import org.apache.commons.lang3.StringUtils;
import org.springframework.util.CollectionUtils;
@Slf4j
public class EmailHelper {
private static final String DEFAULT_SMTP_HOST = "12.12.12.12";
private static final Integer DEFAULT_SMTP_PORT = 25;
private static final String DEFAULT_MAIL_SENDER = "test@aby.com.cn";
/**
* 邮件发送
*
* @param to 收件人邮件地址列表
* @param subject 邮件标题
* @param content 邮件内容
* @return 发送结果
*/
public static boolean send(List<String> to, String subject, String content) {
return send(to, null, null, subject, content, null);
}
/**
* 邮件发送
*
* @param to 收件人邮件地址列表
* @param subject 邮件标题
* @param content 邮件内容
* @param attachments 附件
* @return 发送结果
*/
public static boolean send(List<String> to, String subject, String content, List<File> attachments) {
return send(to, null, null, subject, content, attachments);
}
/**
* 邮件发送
*
* @param to 收件人邮件地址列表
* @param cc 抄送人邮件地址列表
* @param subject 邮件标题
* @param content 邮件内容
* @param attachments 附件
* @return 发送结果
*/
public static boolean send(List<String> to, List<String> cc, String subject, String content, List<File> attachments) {
return send(to, cc, null, subject, content, attachments);
}
/**
* 邮件发送
*
* @param to 收件人邮件地址列表
* @param cc 抄送人邮件地址列表
* @param bcc 密送人邮件地址列表
* @param subject 邮件标题
* @param content 邮件内容
* @param attachments 附件
* @param sender 发件人
* @return 发送结果
*/
public static boolean send(List<String> to, List<String> cc, List<String> bcc,
String subject, String content, List<File> attachments,String sender) {
return send(DEFAULT_SMTP_HOST, DEFAULT_SMTP_PORT, sender, null, to, cc, bcc, subject, content, attachments);
}
/**
* 邮件发送
*
* @param to 收件人邮件地址列表
* @param cc 抄送人邮件地址列表
* @param bcc 密送人邮件地址列表
* @param subject 邮件标题
* @param content 邮件内容
* @param attachments 附件
* @return 发送结果
*/
public static boolean send(List<String> to, List<String> cc, List<String> bcc,
String subject, String content, List<File> attachments) {
return send(DEFAULT_SMTP_HOST, DEFAULT_SMTP_PORT, DEFAULT_MAIL_SENDER, null, to, cc, bcc, subject, content, attachments);
}
/**
* 邮件发送
*
* @param smtpHost smtp服务地址
* @param smtpPort smtp服务端口
* @param sender 发送人邮箱地址
* @param senderPassword 发送人邮箱密码
* @param to 收件人邮件地址列表
* @param cc 抄送人邮件地址列表
* @param bcc 密送人邮件地址列表
* @param subject 邮件标题
* @param content 邮件内容
* @param attachments 附件
* @return 发送结果
*/
public static boolean send(String smtpHost, Integer smtpPort, String sender, String senderPassword,
List<String> to, List<String> cc, List<String> bcc,
String subject, String content, List<File> attachments) {
MimeMessage message = getMimeMessage(smtpHost, smtpPort, sender, senderPassword);
try {
// 收件人
List<InternetAddress> toInternetAddressList = convertToInternetAddress(to);
if (CollectionUtils.isEmpty(toInternetAddressList)) {
log.error("邮件收件人不能为空");
return false;
}
message.addRecipients(Message.RecipientType.TO, toInternetAddressList.toArray(new InternetAddress[0]));
// 抄送人
List<InternetAddress> ccInternetAddressList = convertToInternetAddress(cc);
if (!CollectionUtils.isEmpty(ccInternetAddressList)) {
message.addRecipients(Message.RecipientType.CC, ccInternetAddressList.toArray(new InternetAddress[0]));
}
// 密送人
List<InternetAddress> bccInternetAddressList = convertToInternetAddress(bcc);
if (!CollectionUtils.isEmpty(bccInternetAddressList)) {
message.addRecipients(Message.RecipientType.BCC, bccInternetAddressList.toArray(new InternetAddress[0]));
}
// 内容
Multipart multipart = new MimeMultipart();
MimeBodyPart contentPart = new MimeBodyPart();
contentPart.setContent(content, "text/html;charset=utf-8");
multipart.addBodyPart(contentPart);
// 附件
if (!CollectionUtils.isEmpty(attachments)) {
attachments.forEach(file -> {
try {
MimeBodyPart filePartBody = new MimeBodyPart();
DataSource fileDataSource = new FileDataSource(file);
DataHandler dataHandler = new DataHandler(fileDataSource);
filePartBody.setDataHandler(dataHandler);
filePartBody.setFileName(MimeUtility.encodeText(file.getName()));
multipart.addBodyPart(filePartBody);
} catch (Exception e) {
log.error("邮件中的附件失败,已经丢弃该附件:{}", file.getName());
}
});
}
message.setContent(multipart);
message.setFrom(new InternetAddress(sender));
String mailSubject = StringUtils.isNotBlank(subject) ? subject : "无主题";
String activeProfile = System.getProperty("spring.profiles.active");
if (StringUtils.isNotBlank(activeProfile) && !activeProfile.contains("online")) {
mailSubject += String.format(" 【环境: %s】", activeProfile);
}
message.setSubject(mailSubject, "UTF-8");
message.saveChanges();
Transport.send(message);
return true;
} catch (MessagingException ex) {
log.error("error when send email.", ex);
return false;
}
}
private static MimeMessage getMimeMessage(String smtpHost, Integer smtpPort, String sender, String senderPassword) {
Properties properties = new Properties();
properties.put("mail.transport.protocol", "smtp");
properties.put("mail.smtp.host", smtpHost);
properties.put("mail.smtp.port", smtpPort);
Authenticator authenticator = null;
if (StringUtils.isNotBlank(sender) && StringUtils.isNotBlank(senderPassword)) {
authenticator = new Authenticator() {
@Override
protected PasswordAuthentication getPasswordAuthentication() {
return new PasswordAuthentication(sender, senderPassword);
}
};
}
properties.put("mail.smtp.auth", authenticator != null ? "true" : "false");
Session session = Session.getDefaultInstance(properties, authenticator);
return new MimeMessage(session);
}
private static List<InternetAddress> convertToInternetAddress(List<String> mailAddressList) {
if (CollectionUtils.isEmpty(mailAddressList)) {
return new ArrayList<>();
}
List<InternetAddress> mailInternetAddress = new ArrayList<>();
mailAddressList.forEach(item -> {
try {
mailInternetAddress.add(new InternetAddress(item));
} catch (AddressException e) {
log.error("邮件地址错误,此邮件地址不参与邮件的接收:{}", item);
}
});
return mailInternetAddress;
}
}