【已实测通过】JavaMail常用的几种邮件发送方式

【我的Segmentfault原文】https://segmentfault.com/a/1190000008114373

 

前言

  关于JavaMail发送邮件的代码，网上随便搜搜就可以找到，但是要么写得简单且没有注释解释，要么写得复杂又非常杂乱。由于项目需要，花了一段时间搜集网上各类案例，熟悉JavaMail邮件发送涉及的配置，取其精华去其糟粕。在功能测试正常可用的前提下，对代码的排版和注释进行梳理调整，提炼出符合自己要求的功能代码，现将它分享给大家，希望大家少走弯路，提高开发效率。代码测试过程出现的问题，请参看《JavaMail邮件发送成功但未收到邮件的问题及解决办法》和《使用geronimo-javamail_1.4发送邮件的有关说明》分析解决。

主要类及功能

1、EmailAuthenticator类：继承Authenticator类的账号密码验证器，主要用于创建邮件会话时调用。
2、EmailSendInfo类：邮件参数信息设置，参数包括账号、密码、SMTP服务器地址和服务端口等。
3、EmailSender类：电子邮件发送器，包含各种邮件发送方法，如文本形式、HTML形式和含附件形式等。
注：请到Oracle官网下载JavaMail的jar包，提供以下参考下载地址：

http://www.oracle.com/technet...
https://java.net/projects/jav...

EmailAuthenticator类

import javax.mail.*;   

public class EmailAuthenticator extends Authenticator{   
    
    private String userName;   
    private String password;   
        
    public EmailAuthenticator(){}   
    
    public EmailAuthenticator(String username, String password) {    
        this.userName = username;    
        this.password = password;    
    }    
    
    protected PasswordAuthentication getPasswordAuthentication(){   
        return new PasswordAuthentication(userName, password);   
    }
    
    public String getUserName() {
        return userName;
    }
    
    public void setUserName(String userName) {
        this.userName = userName;
    }
    
    public String getPassword() {
        return password;
    }
    
    public void setPassword(String password) {
        this.password = password;
    }   
    
}   

EmailSendInfo类

import java.util.Properties;

public class EmailSendInfo {
    
    // 发送邮件的服务器的IP和端口
    private String mailServerHost;
    private String mailServerPort = "25";
    // 邮件发送者的地址
    private String fromAddress;
    // 邮件接收者的地址
    private String toAddress;
    // 登陆邮件发送服务器的用户名和密码
    private String userName;
    private String password;
    // 是否需要身份验证
    private boolean validate = false;
    // 邮件主题
    private String subject;
    // 邮件的文本内容
    private String content;
    // 邮件附件的文件名
    private String[] attachFileNames;

    /**
     * 获得邮件会话属性
     */
    public Properties getProperties() {
        Properties p = new Properties();
        p.put("mail.smtp.host", this.mailServerHost);
        p.put("mail.smtp.port", this.mailServerPort);
        p.put("mail.smtp.auth", validate ? "true" : "false");
        return p;
    }

    public String getMailServerHost() {
        return mailServerHost;
    }

    public void setMailServerHost(String mailServerHost) {
        this.mailServerHost = mailServerHost;
    }

    public String getMailServerPort() {
        return mailServerPort;
    }

    public void setMailServerPort(String mailServerPort) {
        this.mailServerPort = mailServerPort;
    }

    public boolean isValidate() {
        return validate;
    }

    public void setValidate(boolean validate) {
        this.validate = validate;
    }

    public String[] getAttachFileNames() {
        return attachFileNames;
    }

    public void setAttachFileNames(String[] fileNames) {
        this.attachFileNames = fileNames;
    }

    public String getFromAddress() {
        return fromAddress;
    }

    public void setFromAddress(String fromAddress) {
        this.fromAddress = fromAddress;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }

    public String getToAddress() {
        return toAddress;
    }

    public void setToAddress(String toAddress) {
        this.toAddress = toAddress;
    }

    public String getUserName() {
        return userName;
    }

    public void setUserName(String userName) {
        this.userName = userName;
    }

    public String getSubject() {
        return subject;
    }

    public void setSubject(String subject) {
        this.subject = subject;
    }

    public String getContent() {
        return content;
    }

    public void setContent(String textContent) {
        this.content = textContent;
    }
}

EmailSender类

  为了方面大家阅读，我将EmailSender类的内容进行了拆分，测试使用只需要将下面内容组合就可。其中main方法中的部分参数信息需要自行设置，请勿直接粘贴测试。

import配置

import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.Date;
import java.util.Properties;
import javax.activation.DataHandler;
import javax.activation.FileDataSource;
import javax.mail.Address;
import javax.mail.BodyPart;
import javax.mail.Message;
import javax.mail.MessagingException;
import javax.mail.Multipart;
import javax.mail.Session;
import javax.mail.Transport;
import javax.mail.internet.InternetAddress;
import javax.mail.internet.MimeBodyPart;
import javax.mail.internet.MimeMessage;
import javax.mail.internet.MimeMultipart;

用于测试的main方法

public static void main(String[] args) {
    String fromaddr = "XXX@sohu.com";
    String toaddr = "XXX@sohu.com";
//        String title = "【测试标题】Testing Subject-myself-TEXT";
//        String title = "【测试标题】Testing Subject-myself-HTML";
//        String title = "【测试标题】Testing Subject-myself-eml文件";
    String title = "【测试标题】Testing Subject-myself-eml文件_含多个附件";
    String content = "【测试内容】Hello, this is sample for to check send email using JavaMailAPI ";
    String port = "25";
    String host = "smtp.sohu.com";
    String userName = "XXX@sohu.com";
    String password = "XXX";
    
    EmailSendInfo mailInfo = new EmailSendInfo();
     mailInfo.setMailServerHost(host);     
     mailInfo.setMailServerPort(port);    
     mailInfo.setValidate(true); 
     mailInfo.setUserName(userName);    
     mailInfo.setPassword(password);
     mailInfo.setFromAddress(fromaddr);    
     mailInfo.setToAddress(toaddr);    
     mailInfo.setSubject(title);    
     mailInfo.setContent(content);
     mailInfo.setAttachFileNames(new String[]{"file/XXX.jpg","file/XXX.txt"});
      
     //发送文体格式邮件
//         EmailSender.sendTextMail(mailInfo);
     //发送html格式邮件
//         EmailSender.sendHtmlMail(mailInfo);  
     //发送含附件的邮件
     EmailSender.sendAttachmentMail(mailInfo);
     //读取eml文件发送
//         File emailFile = new File("file/EML_myself-eml.eml");
//         File emailFile = new File("file/EML_reademl-eml文件_含文本附件.eml");
//         File emailFile = new File("file/EML_reademl-eml文件_含图片附件.eml");
//         File emailFile = new File("file/EML_reademl-eml文件_含多个附件.eml");
//         EmailSender.sendMail(mailInfo, emailFile);
}

以文本格式发送邮件

public static boolean sendTextMail(EmailSendInfo mailInfo) {   
    boolean sendStatus = false;//发送状态
    // 判断是否需要身份认证    
    EmailAuthenticator authenticator = null;    
    Properties pro = mailInfo.getProperties();
    if (mailInfo.isValidate()) {    
    // 如果需要身份认证，则创建一个密码验证器    
      authenticator = new EmailAuthenticator(mailInfo.getUserName(), mailInfo.getPassword());    
    }   
    // 根据邮件会话属性和密码验证器构造一个发送邮件的session  
    Session sendMailSession = Session.getInstance(pro, authenticator);    
    //【调试时使用】开启Session的debug模式
    sendMailSession.setDebug(true);
    try {    
        // 根据session创建一个邮件消息    
        MimeMessage  mailMessage = new MimeMessage(sendMailSession);    
        // 创建邮件发送者地址    
        Address from = new InternetAddress(mailInfo.getFromAddress());    
        // 设置邮件消息的发送者    
        mailMessage.setFrom(from);    
        // 创建邮件的接收者地址，并设置到邮件消息中    
        Address to = new InternetAddress(mailInfo.getToAddress());    
        mailMessage.setRecipient(Message.RecipientType.TO,to);    
        // 设置邮件消息的主题    
        mailMessage.setSubject(mailInfo.getSubject(), "UTF-8");
        // 设置邮件消息发送的时间    
        mailMessage.setSentDate(new Date());    
        // 设置邮件消息的主要内容    
        String mailContent = mailInfo.getContent();    
        mailMessage.setText(mailContent, "UTF-8"); 
//            mailMessage.saveChanges(); 
        
        //生成邮件文件
        createEmailFile("file/EML_myself-TEXT.eml", mailMessage); 
        
        // 发送邮件    
        Transport.send(mailMessage);   
        sendStatus = true;    
    } catch (MessagingException ex) {    
          LOG.error("以文本格式发送邮件出现异常", ex);
          return sendStatus;
    }    
    return sendStatus;    
}

以HTML格式发送邮件

public static boolean sendHtmlMail(EmailSendInfo mailInfo){   
    boolean sendStatus = false;//发送状态
    // 判断是否需要身份认证    
    EmailAuthenticator authenticator = null;   
    Properties pro = mailInfo.getProperties();   
    //如果需要身份认证，则创建一个密码验证器     
    if (mailInfo.isValidate()) {    
      authenticator = new EmailAuthenticator(mailInfo.getUserName(), mailInfo.getPassword());   
    }    
    // 根据邮件会话属性和密码验证器构造一个发送邮件的session    
    Session sendMailSession = Session.getDefaultInstance(pro,authenticator);  
    //【调试时使用】开启Session的debug模式
    sendMailSession.setDebug(true);
    try {    
        // 根据session创建一个邮件消息    
        Message mailMessage = new MimeMessage(sendMailSession);    
        // 创建邮件发送者地址    
        Address from = new InternetAddress(mailInfo.getFromAddress());    
        // 设置邮件消息的发送者    
        mailMessage.setFrom(from);    
        // 创建邮件的接收者地址，并设置到邮件消息中    
        Address to = new InternetAddress(mailInfo.getToAddress());    
        // Message.RecipientType.TO属性表示接收者的类型为TO    
        mailMessage.setRecipient(Message.RecipientType.TO,to);    
        // 设置邮件消息的主题    
        mailMessage.setSubject(mailInfo.getSubject());    
        // 设置邮件消息发送的时间    
        mailMessage.setSentDate(new Date());    
        // 设置邮件内容
        mailMessage.setContent(mailInfo.getContent(), "text/html;charset=utf-8");
        
        //生成邮件文件
        createEmailFile("file/EML_myself-HTML.eml", mailMessage);
        
        // 发送邮件    
        Transport.send(mailMessage);    
        sendStatus = true;    
    } catch (MessagingException ex) {    
        LOG.error("以HTML格式发送邮件出现异常", ex);    
        return sendStatus;
    }    
    return sendStatus;    
}  

读取eml文件后发送邮件

public static boolean sendMail(EmailSendInfo mailInfo, File emailFile) {
    boolean sendStatus = false;//发送状态
    // 判断是否需要身份认证    
    EmailAuthenticator authenticator = null;    
    Properties pro = mailInfo.getProperties();
    if (mailInfo.isValidate()) {    
    // 如果需要身份认证，则创建一个密码验证器    
      authenticator = new EmailAuthenticator(mailInfo.getUserName(), mailInfo.getPassword());    
    }   
    // 根据邮件会话属性和密码验证器构造一个发送邮件的session  
    Session sendMailSession = Session.getInstance(pro, authenticator);    
    //【调试时使用】开启Session的debug模式
    sendMailSession.setDebug(true);
    try {    
        InputStream source = new FileInputStream(emailFile);
        // 根据session创建一个邮件消息    
         Message  mailMessage = new MimeMessage(sendMailSession, source);    
        // 发送邮件    
        Transport.send(mailMessage);   
        //【重要】关闭输入流，否则会导致文件无法移动或删除
        source.close();
        sendStatus = true;    
    } catch (MessagingException e) {    
          LOG.error("以文本格式发送邮件出现异常", e);
          return sendStatus;
    } catch (FileNotFoundException e) {
        LOG.error("FileNotFoundException", e);
        return sendStatus;   
    } catch (Exception e) {
        LOG.error("Exception", e);
        return sendStatus;
    }
    return sendStatus;    
}

以含附件形式发送邮件

public static boolean sendAttachmentMail(EmailSendInfo mailInfo) {
    boolean sendStatus = false;//发送状态
    // 判断是否需要身份认证    
    EmailAuthenticator authenticator = null;    
    Properties pro = mailInfo.getProperties();
    if (mailInfo.isValidate()) {    
    // 如果需要身份认证，则创建一个密码验证器    
      authenticator = new EmailAuthenticator(mailInfo.getUserName(), mailInfo.getPassword());    
    }   
    // 根据邮件会话属性和密码验证器构造一个发送邮件的session  
    Session sendMailSession = Session.getInstance(pro, authenticator);    
    //【调试时使用】开启Session的debug模式
    sendMailSession.setDebug(true);
    try {    
        // 根据session创建一个邮件消息    
        MimeMessage  mailMessage = new MimeMessage(sendMailSession);    
        // 创建邮件发送者地址    
        Address from = new InternetAddress(mailInfo.getFromAddress());    
        // 设置邮件消息的发送者    
        mailMessage.setFrom(from);    
        // 创建邮件的接收者地址，并设置到邮件消息中    
        Address to = new InternetAddress(mailInfo.getToAddress());    
        mailMessage.setRecipient(Message.RecipientType.TO,to);    
        // 设置邮件消息的主题    
        mailMessage.setSubject(mailInfo.getSubject(), "UTF-8");
        // 设置邮件消息发送的时间    
        mailMessage.setSentDate(new Date());    
        // 设置邮件消息的主要内容    
        String mailContent = mailInfo.getContent();   
        // MiniMultipart类是一个容器类，包含MimeBodyPart类型的对象    
        Multipart mainPart = new MimeMultipart();    
        // 创建一个包含HTML内容的MimeBodyPart    
        BodyPart bodyPart = new MimeBodyPart();    
        //设置TEXT内容
//            bodyPart.setText(mailInfo.getContent());
        // 设置HTML内容    
        bodyPart.setContent(mailInfo.getContent(), "text/html; charset=utf-8");    
        mainPart.addBodyPart(bodyPart);    
        //设置附件
         String[] filenames = mailInfo.getAttachFileNames();
         for (int i = 0; i < filenames.length; i++) {
             // Part two is attachment  
             bodyPart = new MimeBodyPart();  
             String filename = filenames[i];//1.txt/sohu_mail.jpg
//                 DataSource source = new FileDataSource(filename);  
             FileDataSource source = new FileDataSource(filename); 
             bodyPart.setDataHandler(new DataHandler(source));  
             bodyPart.setFileName(source.getName());  
             mainPart.addBodyPart(bodyPart);  
        }
        // 将MiniMultipart对象设置为邮件内容    
        mailMessage.setContent(mainPart); 
        
        //生成邮件文件
        createEmailFile("file/EML_reademl-eml文件_含多个附件.eml", mailMessage); 
        
        // 发送邮件    
        Transport.send(mailMessage);   
        sendStatus = true;    
    } catch (MessagingException ex) {    
          LOG.error("以文本格式发送邮件出现异常", ex);
          return sendStatus;
    }    
    return sendStatus;    
}

生成邮件文件

public static void createEmailFile(String fileName, Message mailMessage)
        throws MessagingException {
    
    File f = new File(fileName); 
    try {
        mailMessage.writeTo(new FileOutputStream(f));
    } catch (IOException e) {
        LOG.error("IOException", e);  
    }
}