javaWeb之自动发送邮件生日祝福(ServletContextListener监听)

在看完本随笔仍然不理解的可以看  javaWeb邮箱发送  ：里面有具体的邮箱服务器配置

企业在员工生日当天发送邮箱生日祝福：

一般是用监听器完成：  而合适的监听是ServletContextListener   ，每天都定时查看该天过生日的员工，并发送邮件祝福

创建一个监听器：

package com.study.mail;

import java.sql.SQLException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.List;
import java.util.Timer;
import java.util.TimerTask;

import javax.mail.MessagingException;
import javax.mail.internet.AddressException;
import javax.servlet.ServletContextEvent;
import javax.servlet.ServletContextListener;

import org.apache.commons.dbutils.QueryRunner;
import org.apache.commons.dbutils.handlers.BeanListHandler;

import com.study.utils.DataSourceUtils;

public class MyServletContextListener implements ServletContextListener {

    public void contextInitialized(ServletContextEvent arg0)  {
        Timer timer=new Timer();
        final SimpleDateFormat sdf=new SimpleDateFormat("MM-dd");
        final QueryRunner qr=new QueryRunner(DataSourceUtils.getDataSource());
         timer.schedule(new TimerTask() {
            @Override
            public void run() {

                //判断今天的日期
                String today="\"%"+sdf.format(new Date())+"%\"";
                // today 容易写成      "%"+sdf.format(new Date())+"%"
                // 导致生成的sql语句为：  select * from user where birthday like %11-13%
                // 正常运行的sql语句为：   select * from user where birthday like  "%11-13%"，
                //因此使用   ‘\’  转义符把  " 转化  

                //今天生日的员工
                String sql="select * from user where birthday like "+today;
                List<User> userList =null;
                try {
                System.out.println(sql);
                userList = qr.query(sql, new BeanListHandler<User>(User.class));
                } catch (SQLException e) {
                    e.printStackTrace();
                }
                if (userList!=null) {
                    for (User user : userList) {
                        String emailMsg="亲爱的"+user.getName()+"<br/>祝你生日快乐";
                        try {
                            MailUtils.sendMail(user.getEmail(), "生日祝福", emailMsg);
                        } catch (AddressException e) {
                            e.printStackTrace();
                        } catch (MessagingException e) {
                            e.printStackTrace();
                        }
                    }
                }
            }
        }, new Date(), 1000*5);
         //new Date()  具体的项目不为这个, 1000*5  // 真正项目是1000*60*60*24 一天
    }

    public void contextDestroyed(ServletContextEvent arg0)  {
         // TODO Auto-generated method stub
    }

}

User  类：

package com.study.mail;

public class User {

    private String name;
    private String passWord;
    private String email;
    private String birthday;

    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public String getPassWord() {
        return passWord;
    }
    public void setPassWord(String passWord) {
        this.passWord = passWord;
    }
    public String getEmail() {
        return email;
    }
    public void setEmail(String email) {
        this.email = email;
    }
    public String getBirthday() {
        return birthday;
    }
    public void setBirthday(String birthday) {
        this.birthday = birthday;
    }

}

MailUtils类：

package com.study.mail;

import java.util.Properties;

import javax.mail.Authenticator;
import javax.mail.Message;
import javax.mail.MessagingException;
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.MimeMessage;
import javax.mail.internet.MimeMessage.RecipientType;

public class MailUtils {

    public static void sendMail(String email,String subject, String emailMsg)
            throws AddressException, MessagingException {
        // 1.创建一个程序与邮件服务器会话对象 Session

        Properties props = new Properties();
        props.setProperty("mail.transport.protocol", "SMTP");//发送邮件的协议
        props.setProperty("mail.host", "localhost");//发送邮件的服务器地址
        props.setProperty("mail.smtp.auth", "true");// 指定验证为true

        // 创建验证器
        Authenticator auth = new Authenticator() {
            public PasswordAuthentication getPasswordAuthentication() {
                return new PasswordAuthentication("tom", "123456");//发送邮件的账号认证
            }
        };

        Session session = Session.getInstance(props, auth);

        // 2.创建一个Message，它相当于是邮件内容
        Message message = new MimeMessage(session);

        message.setFrom(new InternetAddress("tom@study.com")); // 设置发送者

        message.setRecipient(RecipientType.TO, new InternetAddress(email)); // 设置发送方式与接收者

        message.setSubject(subject);//设置邮件的主题
        // message.setText("这是一封激活邮件，请<a href='#'>点击</a>");
        //设置邮件的内容
        message.setContent(emailMsg, "text/html;charset=utf-8");

        // 3.创建 Transport用于将邮件发送

        Transport.send(message);
    }
}

DataSourceUtils类

package com.study.utils;

import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;

import javax.sql.DataSource;

import com.mchange.v2.c3p0.ComboPooledDataSource;

public class DataSourceUtils {

    private static DataSource dataSource = new ComboPooledDataSource();

    private static ThreadLocal<Connection> tl = new ThreadLocal<Connection>();

    // 直接可以获取一个连接池
    public static DataSource getDataSource() {
        return dataSource;
    }

    public static Connection getConnection() throws SQLException{
        return dataSource.getConnection();
    }

    // 获取连接对象
    public static Connection getCurrentConnection() throws SQLException {

        Connection con = tl.get();
        if (con == null) {
            con = dataSource.getConnection();
            tl.set(con);
        }
        return con;
    }

    // 开启事务
    public static void startTransaction() throws SQLException {
        Connection con = getCurrentConnection();
        if (con != null) {
            con.setAutoCommit(false);
        }
    }

    // 事务回滚
    public static void rollback() throws SQLException {
        Connection con = getCurrentConnection();
        if (con != null) {
            con.rollback();
        }
    }

    // 提交并且 关闭资源及从ThreadLocall中释放
    public static void commitAndRelease() throws SQLException {
        Connection con = getCurrentConnection();
        if (con != null) {
            con.commit(); // 事务提交
            con.close();// 关闭资源
            tl.remove();// 从线程绑定中移除
        }
    }

    // 关闭资源方法
    public static void closeConnection() throws SQLException {
        Connection con = getCurrentConnection();
        if (con != null) {
            con.close();
        }
    }

    public static void closeStatement(Statement st) throws SQLException {
        if (st != null) {
            st.close();
        }
    }

    public static void closeResultSet(ResultSet rs) throws SQLException {
        if (rs != null) {
            rs.close();
        }
    }

}

C3p0-config.xml

<?xml version="1.0" encoding="UTF-8"?>
<c3p0-config>
    <default-config>
        <property name="user">root</property>
        <property name="password">root</property>
        <property name="driverClass">com.mysql.jdbc.Driver</property>
        <property name="jdbcUrl">jdbc:mysql:///WEBListener</property>
    </default-config>
</c3p0-config> 

mysql数据库：

foxmail用户

应用开启：生日当天的user收到邮件