Java发送邮件工具类

        <dependency>
            <groupId>commons-beanutils</groupId>
            <artifactId>commons-beanutils</artifactId>
            <version>1.9.3</version>
        </dependency>

        <dependency>
            <groupId>commons-logging</groupId>
            <artifactId>commons-logging</artifactId>
            <version>1.2</version>
        </dependency>

        <!-- https://mvnrepository.com/artifact/javax.mail/mail -->
        <dependency>
            <groupId>javax.mail</groupId>
            <artifactId>mail</artifactId>
            <version>1.4.6</version>
        </dependency>

package com.jiangwenzhang.dto;

import java.util.Date;


/**
 * 上午9:29:51
 * 
 * @version V1.0
 */
public class MimeMessageDTO {
    /**   
     * 变量名 subject: TODO 邮件标题
     */   
    private String subject;
    
    /**   
     * 变量名 sentDate: TODO 邮件日期
     */   
    private Date sentDate;
    
    /**   
     * 变量名 text: TODO 邮件内容
     */   
    private String text;

    /** 
     * 方法名: initMimeMessage 
     * 功能描述: TODO 初始化
     * @param: @param subject
     * @param: @param date
     * @param: @param text
     * @param: @return  
     * @return: MimeMessageDTO 
     */
    public MimeMessageDTO initMimeMessage(String subject, Date date, String text) {
        return new MimeMessageDTO(subject, date, text);
    }
    
    public MimeMessageDTO() {
        super();
    }

    public MimeMessageDTO(String subject, Date sentDate, String text) {
        super();
        this.subject = subject;
        this.sentDate = sentDate;
        this.text = text;
    }

    public String getSubject() {
        return subject;
    }

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

    public Date getSentDate() {
        return sentDate;
    }

    public void setSentDate(Date sentDate) {
        this.sentDate = sentDate;
    }

    public String getText() {
        return text;
    }

    public void setText(String text) {
        this.text = text;
    }

}

package com.jiangwenzhang.util;

import com.jiangwenzhang.dto.MimeMessageDTO;

import java.util.List;
import java.util.Properties;

import javax.activation.DataHandler;
import javax.activation.FileDataSource;
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;


/**
 * 类名称:  mailUtil
 * 功能描述: TODO 邮件发送例子
 * 创建人:  Gavin-Nie 
 * 创建时间: 2014-12-4 上午9:20:16 
 * @version  V1.0  
 */
public class MailUtil {
    
    /**   
     * 变量名 userName: TODO 邮箱用户名
     */   
    private String userName;
    
    /**   
     * 变量名 password: TODO 邮箱地址
     */   
    private String password;
    
    /**   
     * 变量名 smtpHost: TODO 邮箱smtp地址，发送地址
     */   
    private String smtpHost;
    
    /**   
     * 变量名 targetAddress: TODO 目标邮箱地址
     */   
    private String targetAddress;
    
    /**
     *  发送单邮件
     * @param userName
     * @param password
     * @param targetAddress
     * @param mimeDTO
     * @return
     */
    public  static boolean sendEmail(String userName,String password,String targetAddress,
            MimeMessageDTO mimeDTO){
        return publicsendEmail(userName,password,targetAddress,mimeDTO,false,null);
    }
    /**
     * 发送单邮件(附件)
     * @param userName
     * @param password
     * @param targetAddress
     * @param mimeDTO
     * @param filepath        文件本地绝对路径
     * @return
     */
    public  static boolean sendEmailByFile(String userName,String password,String targetAddress,
            MimeMessageDTO mimeDTO,List<String> filepath){
        return publicsendEmail(userName,password,targetAddress,mimeDTO,true,filepath);
    }
    /**
     * 群发邮件 
     * @param userName
     * @param password
     * @param targetAddress   多个邮件发送地址，以,分隔
     * @param mimeDTO
     * @return
     */
    public  static boolean sendGroupEmail(String userName,String password,String targetAddress,
            MimeMessageDTO mimeDTO){
        return publicsendEmail(userName,password,targetAddress,mimeDTO,true,null);
    }
    /**
     * 群发邮件 (附件)
     * @param userName
     * @param password
     * @param targetAddress 多个邮件发送地址，以,分隔
     * @param mimeDTO
     * @param filepath      文件本地绝对路径
     * @return
     */
    public  static boolean sendGroupEmailByFile(String userName,String password,String targetAddress,
            MimeMessageDTO mimeDTO,List<String> filepath){
        return publicsendEmail(userName,password,targetAddress,mimeDTO,true,filepath);
    }
    
    
    
    /**
     * 邮件发送基础方法
     * @param userName
     * @param password
     * @param targetAddress
     * @param mimeDTO
     * @param isGroup
     * @param filepath
     * @return
     */
    private static boolean publicsendEmail(String userName,String password,String targetAddress,
            MimeMessageDTO mimeDTO,boolean isGroup,List<String> filepath){
        Properties props = makeMailProperties(userName);
        String hostname=SMTPUtil.SimpleMailSender(userName);
        Session session = Session.getInstance(props, new PopupAuthenticator(userName, password));
        session.setDebug(true);
        try {
            Transport ts = session.getTransport();
            ts.connect(hostname,userName,password);
            Message message =!isGroup?createEmail(session,userName,targetAddress,mimeDTO)
                    :createEmailByGroupAndFile(session,userName,
                            targetAddress,mimeDTO,filepath==null?null:filepath);
            ts.sendMessage(message,message.getAllRecipients());
            ts.close();
        } catch (Exception mex) {
            mex.printStackTrace();
            return false;
        }
        return true;
    }
    
    
    
    
    
    /**
     * 创建邮件信息
     * @param userName
     * @return
     */
    private static Properties makeMailProperties(String userName){
        Properties props = new Properties();
        String hostname=SMTPUtil.SimpleMailSender(userName);
        props.put("mail.smtp.host", hostname);
        props.setProperty("mail.smtp.auth", "true");
        props.setProperty("mail.transport.protocol", "smtp");
        if(hostname.indexOf(".qq.com")!=-1){
            props.setProperty("mail.smtp.socketFactory.port", "465");
            props.setProperty("mail.smtp.socketFactory.class", "javax.net.ssl.SSLSocketFactory");
        }
        return props;
    }
    
    
    
    /**
     * 创建邮件
     * @Author Casper
     * Create_time:2015年10月17日 下午7:45:57
     * description:
     */
    private static Message createEmail(Session session,String userName,String regMail,MimeMessageDTO mimeDTO){
        MimeMessage message = new MimeMessage(session);
        try {
            message.setFrom(new InternetAddress(userName));
            message.setRecipient(Message.RecipientType.TO, new InternetAddress(regMail));
            message.setSubject(mimeDTO.getSubject());
            message.setContent(mimeDTO.getText(),"text/html;charset=UTF-8");
            message.saveChanges();
        } catch (MessagingException e) {
            e.printStackTrace();
        }
        return message;
    }
    /**
     * 创建群发带附件
     * @return
     */
    private static Message createEmailByGroupAndFile(Session session,String userName,
                                String regMail,MimeMessageDTO mimeDTO,List<String> filepath){
        MimeMessage message = new MimeMessage(session);
        try {
            message.setFrom(new InternetAddress(userName));
              // 创建收件人列表  
            if (regMail != null && regMail.trim().length() > 0) {  
                String[] arr = regMail.split(",");  
                int receiverCount = arr.length; 
                if (receiverCount > 0) {
                    InternetAddress[] address = new InternetAddress[receiverCount];  
                    for (int i = 0; i < receiverCount; i++) {  
                        address[i] = new InternetAddress(arr[i]);  
                    }  
                    message.setRecipients(Message.RecipientType.TO, address);
                }
            }
         // 后面的BodyPart将加入到此处创建的Multipart中  
            Multipart mp = new MimeMultipart();  
         // 附件操作  
            if (filepath != null && filepath.size() > 0) {  
                for (String filename : filepath) {  
                    MimeBodyPart mbp = new MimeBodyPart();  
                    // 得到数据源  
                    FileDataSource fds = new FileDataSource(filename);  
                    // 得到附件本身并至入BodyPart  
                    mbp.setDataHandler(new DataHandler(fds));  
                    // 得到文件名同样至入BodyPart  
                    mbp.setFileName(fds.getName());  
                    mp.addBodyPart(mbp);  
                }  
                MimeBodyPart mbp = new MimeBodyPart();  
                mbp.setText(mimeDTO.getText());  
                mp.addBodyPart(mbp);  
                // 移走集合中的所有元素  
                filepath.clear();  
                // Multipart加入到信件  
                message.setContent(mp);  
            } else {  
                // 设置邮件正文  
//                message.setText(mimeDTO.getText());  
                message.setContent(mimeDTO.getText(),"text/html;charset=UTF-8");
            } 
            message.setSubject(mimeDTO.getSubject());
            message.saveChanges();
        } catch (MessagingException e) {
            e.printStackTrace();
        }
        return message;
    }
    
    
    
    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;
    }
    public String getSmtpHost() {
        return smtpHost;
    }
    public void setSmtpHost(String smtpHost) {
        this.smtpHost = smtpHost;
    }
    public String getTargetAddress() {
        return targetAddress;
    }
    public void setTargetAddress(String targetAddress) {
        this.targetAddress = targetAddress;
    }
}

  @GetMapping("/send")
    public String sendmail() {
        String userName = "**@qq.com";   //用户邮箱地址
        String password = "**";    //密码或者授权码
        String targetAddress = "**@qq.com";     //接受者邮箱地

        // 设置邮件内容
        MimeMessageDTO mimeDTO = new MimeMessageDTO();
        mimeDTO.setSentDate(new Date());
        mimeDTO.setSubject("提醒：还款");
        mimeDTO.setText("您的信用卡还款日到了");
        String str="发送邮件：";
//        // 发送单邮件
        if (MailUtil.sendEmail(userName, password, targetAddress, mimeDTO)) {
            str+="邮件发送成功！";
        } else {
            str+="邮件发送失败!!!";
        }
        return str;
    }