java 发送邮件，

java 发送邮件，

导入jar包

<!-- 发送邮件-->
 <dependency>
     <groupId>javax.mail</groupId>
     <artifactId>mail</artifactId>
     <version>1.4.7</version>
 </dependency>

package com.utils;

import javax.activation.DataHandler;
import javax.activation.DataSource;
import javax.activation.FileDataSource;
import javax.mail.*;
import javax.mail.internet.InternetAddress;
import javax.mail.internet.MimeBodyPart;
import javax.mail.internet.MimeMessage;
import javax.mail.internet.MimeMultipart;
import javax.xml.transform.Result;
import java.util.Properties;

/**
 * Author:   linjunit
 * Version：
 * Date:     2017/11/10 0010
 * Description:
 * Modification  History:
 * Date            Author            Version            Description
 * --------------------------------------------------------------
 * Why & What is modified:
 */
public class SendEmail {

    /**
     * 发送邮件
     * @param to 发件人
     * @param from 收件人
     * @param host host地址 可选参数
     * @return
     */
    public  static boolean  SendEmail(String to,String from,String host){
        boolean flag=false;
        // 获取系统属性对象
        Properties properties = System.getProperties();

        // 设置邮件服务器
        properties.setProperty("mail.smtp.host", host);

        // 获取默认的Session对象。
        Session mailSession = Session.getDefaultInstance(properties);

        try{
            // 创建一个默认的MimeMessage对象。
            MimeMessage message = new MimeMessage(mailSession);

            // 设置 From: 头部的header字段
            message.setFrom(new InternetAddress(from));

            // 设置 To: 头部的header字段
            message.addRecipient(Message.RecipientType.TO,
                    new InternetAddress(to));

            // 设置 Subject: header字段
            message.setSubject("This is the Subject Line!");

            // 创建消息部分
            BodyPart messageBodyPart = new MimeBodyPart();

            // 填充消息
            messageBodyPart.setText("This is message body");

            // 创建多媒体消息
            Multipart multipart = new MimeMultipart();

            // 设置文本消息部分
            multipart.addBodyPart(messageBodyPart);

            // 附件部分
            messageBodyPart = new MimeBodyPart();
            String filename = "file.txt";
            DataSource source = new FileDataSource(filename);
            messageBodyPart.setDataHandler(new DataHandler(source));
            messageBodyPart.setFileName(filename);
            multipart.addBodyPart(messageBodyPart);

            // 发送完整消息
            message.setContent(multipart );

            // 发送消息
            Transport.send(message);
            String title = "Send Email";
        flag=true;
        }catch (MessagingException mex) {
            mex.printStackTrace();
           flag=false;
        }
        return flag;
    }

}