1、开启SMTP服务
在 QQ 邮箱里的 设置->账户里开启 SMTP 服务 
注意开启完之后，QQ 邮箱会生成一个授权码，在代码里连接邮箱使用这个授权码而不是原始的邮箱密码，这样可以避免使用明文密码。
2、下载依赖的 jar 包
官方下载地址 http://www.oracle.com/technetwork/java/javasebusiness/downloads/java-archive-downloads-eeplat-419426.html#javamail-1.4.7-oth-JPR。
解压完之后，通常我们只需要其中的mail.jar，把它加到我们 java 工程的依赖包中。
package com.weixiaoinfo.framework.util;
import com.sun.mail.util.MailSSLSocketFactory;
import java.io.File;
import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.security.GeneralSecurityException;
import java.util.*;
import javax.activation.DataHandler;
import javax.activation.DataSource;
import javax.activation.FileDataSource;
import javax.mail.Address;
import javax.mail.Authenticator;
import javax.mail.BodyPart;
import javax.mail.Message;
import javax.mail.MessagingException;
import javax.mail.Multipart;
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.MimeBodyPart;
import javax.mail.internet.MimeMessage;
import javax.mail.internet.MimeMultipart;
import javax.mail.internet.MimeUtility;
public class SendMailUtil {
private String username = null;
private String password = null;
private Authenticator auth = null;
private MimeMessage mimeMessage =null;
private Properties pros = null;
private Multipart multipart = null;
private BodyPart bodypart= null;
/**
* 初始化账号密码并验证
* 创建MimeMessage对象
* 发送邮件必须的步骤:1
* @param username
* @param password
*/
public SendMailUtil(String username,String password){
this.username = username;
this.password = password;
}
/**
* 设置email系统参数
* 接收一个map集合key为string类型，值为String
* 发送邮件必须的步骤:2
* @param map
*/
public void setPros(Map<String,String> map) throws GeneralSecurityException {
pros = new Properties();
//可以采用下面端口号 或者使用ssl加密
// MailSSLSocketFactory sf = new MailSSLSocketFactory();
// sf.setTrustAllHosts(true);
// pros.put("mail.smtp.ssl.enable", "true");
// pros.put("mail.smtp.ssl.socketFactory", sf);
for(Map.Entry<String,String> entry:map.entrySet()){
pros.setProperty(entry.getKey(), entry.getValue());
}
}
/**
* 初始化MimeMessage对象 存放邮件内容部分
* 发送邮件必须的步骤:3
*/
public void initMessage(){
this.auth = new Email_Autherticator();
Session session = Session.getDefaultInstance(pros,auth);
session.setDebug(true); //设置获取 debug 信息
mimeMessage = new MimeMessage(session);
}
/**
* 验证账号密码
* 发送邮件必须的步骤
*
*/
public class Email_Autherticator extends Authenticator
{
public PasswordAuthentication getPasswordAuthentication()
{
return new PasswordAuthentication(username, password);
}
}
/**
* 设置发送邮件的基本参数(去除繁琐的邮件设置)
* @param sub 设置邮件主题
* @param text 设置邮件文本内容
* @param rec 设置邮件接收人
* @throws MessagingException
* @throws UnsupportedEncodingException
*/
public void setDefaultMessagePros(String sub,String text,String rec) throws MessagingException, UnsupportedEncodingException{
mimeMessage.setSubject(sub);
mimeMessage.setText(text);
mimeMessage.setRecipient(Message.RecipientType.TO, new InternetAddress(rec));
mimeMessage.setSentDate(new Date());
mimeMessage.setFrom(new InternetAddress(username,username));
}
/**
* 设置主题
* @param subject
* @throws MessagingException
*/
public void setSubject(String subject) throws MessagingException{
mimeMessage.setSubject(subject);
}
/**
* 设置日期
* @param date
* @throws MessagingException
*/
public void setDate(Date date) throws MessagingException{
mimeMessage.setSentDate(new Date());
}
/**
* 设置邮件文本内容
* @param text
* @throws MessagingException
*/
public void setText(String text) throws MessagingException{
mimeMessage.setText(text);
}
/**
* 设置邮件头部
* @param arg0
* @param arg1
* @throws MessagingException
*/
public void setHeader(String arg0,String arg1) throws MessagingException{
mimeMessage.setHeader(arg0, arg1);
}
/**
* 设置邮件接收人地址 <单人发送>
* @param recipient
* @throws MessagingException
*/
public void setRecipient(String recipient) throws MessagingException{
mimeMessage.setRecipient(Message.RecipientType.TO, new InternetAddress(recipient));
}
/**
* 设置邮件接收人地址 <多人发送>
* @param recs 收件人list集合
* @throws MessagingException
* @throws AddressException
*/
public String setRecipients(List<String> recs) throws AddressException, MessagingException{
if(recs.isEmpty()){
return "接收人地址为空!";
}
for(String str:recs){
mimeMessage.addRecipient(Message.RecipientType.TO, new InternetAddress(str));
}
return "加入接收人地址成功!";
}
/**
* 设置邮件接收人地址 <多人发送>
* @param sb 收件人字符串集
* @throws MessagingException
* @throws AddressException
*/
@SuppressWarnings("static-access")
public String setRecipients(StringBuffer sb) throws AddressException, MessagingException{
if(sb==null||"".equals(sb)){
return "字符串数据为空!";
}
Address []address = new InternetAddress().parse(sb.toString());
mimeMessage.addRecipients(Message.RecipientType.TO, address);
return "收件人加入成功";
}
/**
* 设置邮件发送人的名字
* @param from
* @throws UnsupportedEncodingException
* @throws MessagingException
*/
public void setFrom(String from) throws UnsupportedEncodingException, MessagingException{
mimeMessage.setFrom(new InternetAddress(username,from));
}
/**
* 发送邮件<单人发送>
* return 是否发送成功
* @throws MessagingException
*/
public String sendMessage() throws MessagingException{
Transport.send(mimeMessage);
return "success";
}
/**
* 设置附件
* @param file 发送文件的路径
*/
public void setMultipart(String file) throws MessagingException, IOException{
if(multipart==null){
multipart = new MimeMultipart();
}
multipart.addBodyPart(writeFiles(file));
mimeMessage.setContent(multipart);
}
/**
* 设置附件<添加多附件>
* @param fileList<接收List集合>
* @throws MessagingException
* @throws IOException
*/
public void setMultiparts(List<String> fileList) throws MessagingException, IOException{
if(multipart==null){
multipart = new MimeMultipart();
}
for(String s:fileList){
multipart.addBodyPart(writeFiles(s));
}
mimeMessage.setContent(multipart);
}
/**
* 发送文本内容，设置编码方式
* <方法与发送附件配套使用>
* <发送普通的文本内容请使用setText()方法>
* @param s
* @param type
* @throws MessagingException
*/
public void setContent(String s,String type) throws MessagingException{
if(multipart==null){
multipart = new MimeMultipart();
}
bodypart = new MimeBodyPart();
bodypart.setContent(s, type);
multipart.addBodyPart(bodypart);
mimeMessage.setContent(multipart);
mimeMessage.saveChanges();
}
/**
* 读取附件
* @param filePath
* @return
* @throws IOException
* @throws MessagingException
*/
public BodyPart writeFiles(String filePath)throws IOException, MessagingException{
File file = new File(filePath);
if(!file.exists()){
throw new IOException("文件不存在!请确定文件路径是否正确");
}
bodypart = new MimeBodyPart();
DataSource dataSource = new FileDataSource(file);
bodypart.setDataHandler(new DataHandler(dataSource));
//文件名要加入编码，不然出现乱码
bodypart.setFileName(MimeUtility.encodeText(file.getName()));
return bodypart;
}
public static void main(String[] args) throws MessagingException, GeneralSecurityException, IOException {
Map<String,String> map= new HashMap<String,String>();
SendMailUtil mail = new SendMailUtil("***@qq.com","*您的授权码*");
map.put("mail.smtp.auth", "true");
map.put("mail.smtp.host", "smtp.qq.com");
//端口号，QQ邮箱需要使用SSL，端口号465或587
map.put("mail.smtp.socketFactory.class", "javax.net.ssl.SSLSocketFactory");
map.put("mail.smtp.port", "465");
map.put("mail.smtp.socketFactory.port", "465");
mail.setPros(map);
mail.initMessage();
/*
* 添加收件人有三种方法：
* 1,单人添加(单人发送)调用setRecipient(str);发送String类型
* 2,多人添加(群发)调用setRecipients(list);发送list集合类型
* 3,多人添加(群发)调用setRecipients(sb);发送StringBuffer类型
*/
//发送方式1
mail.setRecipient("***@qq.com");
//发送方式2
// List<String> list = new ArrayList<String>();
// list.add("***@qq.com");
// list.add("***@163.com");
// mail.setRecipients(list);
//发送方式3
// String defaultStr = "***@qq.com,***@163.com";
// StringBuffer sb = new StringBuffer();
// sb.append(defaultStr);
// sb.append(",***@qq.com");
// mail.setRecipients(sb);
mail.setSubject("我是邮箱标题呀");
mail.setText("我是邮箱内容呀");
mail.setDate(new Date());
mail.setFrom("我是发件人的名字呀");
// mail.setMultipart("D:你你你.txt");
// mail.setContent("谢谢合作123", "text/html; charset=UTF-8");
// List<String> fileList = new ArrayList<String>();
// fileList.add("D:123.png");
// fileList.add("D:123.txt");
// fileList.add("D:dstz.sql");
// fileList.add("D:软件配置要求.doc");
// mail.setMultiparts(fileList);
System.out.println(mail.sendMessage());
}
}下面是另一个版本的简易版的代码
package com.weixiaoinfo.framework.util;
import com.sun.mail.util.MailSSLSocketFactory;
import javax.mail.*;
import javax.mail.internet.InternetAddress;
import javax.mail.internet.MimeMessage;
import java.security.GeneralSecurityException;
import java.util.Date;
import java.util.Properties;
public class SendMail {
public static void main(String[] args) throws MessagingException, GeneralSecurityException {
Properties props = new Properties();
//开启 SSL 加密
MailSSLSocketFactory sf = new MailSSLSocketFactory();
sf.setTrustAllHosts(true);
props.put("mail.smtp.ssl.enable", "true");
props.put("mail.smtp.ssl.socketFactory", sf);
// 开启debug调试
props.setProperty("mail.debug", "true");
// 发送服务器需要身份验证
props.setProperty("mail.smtp.auth", "true");
// 设置邮件服务器主机名
props.setProperty("mail.host", "smtp.qq.com");
// 发送邮件协议名称
props.setProperty("mail.transport.protocol", "smtp");
Session session = Session.getInstance(props);
//邮件内容部分
Message msg = new MimeMessage(session);
msg.setSubject("我是标题呀");
StringBuilder builder = new StringBuilder();
builder.append("我是您要发送内容");
builder.append("可在内容追加哦");
builder.append("\n data " + new Date());
msg.setText(builder.toString());
//邮件发送者
msg.setFrom(new InternetAddress("***@qq.com"));
//发送邮件
Transport transport = session.getTransport();
transport.connect("smtp.qq.com", "*您的邮箱*", "*授权码*");
//接收人的邮箱地址
transport.sendMessage(msg, new Address[]{new InternetAddress("***@163.com")});
transport.close();
}
}
