注册邮箱

去163邮箱（或其他邮箱）注册一个邮箱，并开启SMTP授权码。

程序

需要注意的是，由于阿里云服务器不让使用默认的25端口，所以会出现Windows下测试发送邮件成功，Linux服务器下发送邮件却出错的问题（broke pipe、timeout、can not connect等）。解决办法是使用带SSL的465端口。

package com.kuyuntech.util;import java.security.Security;
import java.util.Date;
import java.util.Properties;
import javax.mail.Authenticator;
import javax.mail.Message;
import javax.mail.PasswordAuthentication;
import javax.mail.Session;
import javax.mail.Transport;
import javax.mail.internet.InternetAddress;
import javax.mail.internet.MimeMessage;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;/*** 邮件发送工具类*/
public class EmailUtils {/*** 发送邮件的方法* @param toUser    :收件人* @param title     :标题* @param content   :内容*/public static void sendMail(String toUser,String title,String content) throws Exception {// 你自己的邮箱和授权码final String username = "xxxxx@163.com";//自己的邮箱final String password = "xxxxxxxxxx";//授权码，需要登录163邮箱，在设置里设置授权码。授权码用于替代密码Security.addProvider(new com.sun.net.ssl.internal.ssl.Provider());final String SSL_FACTORY = "javax.net.ssl.SSLSocketFactory";Properties props = System.getProperties();props.setProperty("mail.smtp.host", "smtp.163.com");props.setProperty("mail.smtp.socketFactory.class", SSL_FACTORY);props.setProperty("mail.smtp.socketFactory.fallback", "false");props.setProperty("mail.smtp.port", "465");// 不能使用25端口，因为阿里云服务器禁止使用25端口，所以必须使用ssl的465端口props.setProperty("mail.smtp.socketFactory.port", "465");props.put("mail.smtp.auth", "true");Session session = Session.getDefaultInstance(props, new Authenticator(){protected PasswordAuthentication getPasswordAuthentication() {return new PasswordAuthentication(username, password);}});// -- Create a new message --Message msg = new MimeMessage(session);// -- Set the FROM and TO fields --msg.setFrom(new InternetAddress(username));msg.setRecipients(Message.RecipientType.TO,InternetAddress.parse(toUser,false));msg.setSubject(title);msg.setText(content);msg.setSentDate(new Date());Transport.send(msg);}public static void main(String[] args) throws Exception {sendMail("1802226517@qq.com","标题","Hello！");}
}