1、获取表中最后一条数据

 public static String demo() throws SQLException {
     String sql = "select * FROM baoxiu ORDER BY id DESC LIMIT 0,1;";
         PreparedStatement ptmt = conn.prepareStatement(sql);
         ResultSet rs = ptmt.executeQuery();
         String str=null;
     if(rs.next()) {
         str= rs.getString("bt");
     }
     return str;
 }

2、使用模糊查询,获取符合条件的所有数据

 public static List<DuibiModel> getBaoX(String bt) throws SQLException {
     String sql = "select bt,`user`.cardid,phone FROM baoxiu,`user` WHERE baoxiu.cardid=`user`.cardid AND bt LIKE '%"+bt+"%'";
         PreparedStatement ptmt = conn.prepareStatement(sql);
         ResultSet rs = ptmt.executeQuery();
     List<DuibiModel> list = new ArrayList<>() ;
     while(rs.next()) {
         DuibiModel duibi=new DuibiModel();
         duibi.setBt(rs.getString("bt"));
         duibi.setCardid(rs.getString("cardid"));
         duibi.setPhone(rs.getString("phone"));
         list.add(duibi);
     }
     return list;
 }

3、Java 发送邮件

 import javax.mail.Authenticator;
 import javax.mail.PasswordAuthentication;

 public class Auth extends Authenticator {

     private String username = "";
     private String password = "";

     public Auth(String username, String password) {
         this.username = username;
         this.password = password;
     }
     public PasswordAuthentication getPasswordAuthentication() {
         return new PasswordAuthentication(username, password);
     }
 }
 import java.util.Properties;
 import javax.mail.Message;
 import javax.mail.Session;
 import javax.mail.Transport;
 import javax.mail.internet.InternetAddress;
 import javax.mail.internet.MimeMessage;

 public class SendMail {

     private Properties props; //系统属性
     private Session mailSession; //邮件会话对象
     private MimeMessage mimeMsg; //MIME邮件对象

     public SendMail(String SMTPHost, String Port, String MailUsername, String MailPassword) {
         Auth au = new Auth(MailUsername, MailPassword);
         //设置系统属性
         props=java.lang.System.getProperties(); //获得系统属性对象
         props.put("mail.smtp.host", SMTPHost); //设置SMTP主机
         props.put("mail.smtp.port", Port); //设置服务端口号
         props.put("mail.smtp.auth", "true"); //同时通过验证
         //获得邮件会话对象
         mailSession = Session.getInstance(props, au);
     }

     public boolean sendingMimeMail(String MailFrom, String MailTo,
             String MailCopyTo, String MailBCopyTo, String MailSubject,
             String MailBody) {
         try {
             //创建MIME邮件对象
             mimeMsg=new MimeMessage(mailSession);
             //设置发信人
             mimeMsg.setFrom(new InternetAddress(MailFrom));
             //设置收信人
             if(MailTo!=null){
                 mimeMsg.setRecipients(Message.RecipientType.TO, InternetAddress.parse(MailTo));
             }
             //设置抄送人
             if(MailCopyTo!=null){
                 mimeMsg.setRecipients(javax.mail.Message.RecipientType.CC,InternetAddress.parse(MailCopyTo));
             }
             //设置暗送人
             if(MailBCopyTo!=null){
                 mimeMsg.setRecipients(javax.mail.Message.RecipientType.BCC,InternetAddress.parse(MailBCopyTo));
             }
             //设置邮件主题
             mimeMsg.setSubject(MailSubject,"utf-8");
             //设置邮件内容,将邮件body部分转化为HTML格式
             mimeMsg.setContent(MailBody,"text/html;charset=utf-8");
             //发送邮件
             Transport.send(mimeMsg);
             return true;
         } catch (Exception e) {
             e.printStackTrace();
             return false;
         }
     }
 }
 public static boolean email(String email,String str) {
     String SMTPHost="smtp.qq.com";
     String Port="25";
     String MailUsername="[email protected]"; //直接用我的邮件进行发送测试
     String MailPassword="wggddlvcrqfubhde"; //密码请勿修改
     SendMail sendMail=new     SendMail(SMTPHost,Port,MailUsername,MailPassword);
     String MailFrom="[email protected]"; //发件人
     String MailTo=email; //收件人
     String MailCopyTo=null; //抄送人
     String MailBCopyTo=null; //暗送人
     String MailSubject="发现类似商品"; //邮件主题
     String MailBody=str; //邮件内容
     //发送邮件
     boolean isSend=sendMail.sendingMimeMail(MailFrom, MailTo, MailCopyTo, MailBCopyTo, MailSubject, MailBody);
     return isSend;
 }

4、main方法

 public static void main(String[] args) throws SQLException {
     boolean flag = false;
     String str=demo();
     for(DuibiModel duibiModel : getBaoX(str)) {
         System.out.println("名称为:"+duibiModel.getBt()+","+"身份证号:"+duibiModel.getCardid()+","+"电话号码为:"+duibiModel.getPhone());
         flag=email("[email protected]", duibiModel.getBt());
     }
     if(flag) {
         System.out.println("邮件发送成功");
     }else {
         System.out.println("邮件发送失败");
     }
 }
05-20 21:03