package com.sjsq.entity;
/**
 * 邮件实体类
 */
public class Email {
    // 主题
    private String subject;
    // 内容
    private String conetent;
    public String getSubject() {
        return subject;
    }
    public void setSubject(String subject) {
        this.subject = subject;
    }
    public String getConetent() {
        return conetent;
    }
    public void setConetent(String conetent) {
        this.conetent = conetent;
    }
}

package com.sjsq.properties;
/**
 * 邮件参数配置
 */
public class MailProperties {
    // 发件人
    public static final String FROM = "";
    // 发件主机
    public static final String HOST = "";
    // 发件人账号
    public static final String USERNAME = "";
    // 发件人密码
    public static final String PASSWORD = "";
}

package com.sjsq.util;
import com.sjsq.entity.Email;
import com.sjsq.properties.MailProperties;
import javax.mail.*;
import javax.mail.internet.AddressException;
import javax.mail.internet.InternetAddress;
import javax.mail.internet.MimeMessage;
import java.util.Properties;
/**
 * 发送邮件
 */
public class SendMail {
    // 发送邮件
    public static void sendMail(Email email,String address){
        // 定义收件人
        InternetAddress to_address[] = new InternetAddress[1];
        try {
            to_address[0] = new InternetAddress(address);
        } catch (AddressException e) {
            e.printStackTrace();
        }
        // 获取系统属性
        Properties properties = System.getProperties();
        // 设置邮件服务器
        properties.setProperty("mail.smtp.host", MailProperties.HOST);
        properties.put("mail.smtp.auth", "true");
        // 获取默认session对象
        Session session = Session.getDefaultInstance(properties, new Authenticator() {
            @Override
            public PasswordAuthentication getPasswordAuthentication() {
                return new PasswordAuthentication(MailProperties.USERNAME,MailProperties.PASSWORD);
            }
        });
        // 定义头部字段及发邮件
        try {
            // 创建默认的MimeMessage对象
            MimeMessage message = new MimeMessage(session);
            // 设置发件人From 头部字段
            message.setFrom(new InternetAddress(MailProperties.FROM));
            // 设置收件人To 头部字段
            message.addRecipients(Message.RecipientType.TO,to_address);
            // 设置Subject 头部字段
            message.setSubject(email.getSubject());
            // 设置消息体
            message.setText(email.getConetent());
            // 发送消息
            Transport.send(message);
            System.out.println("发送成功");
        } catch (MessagingException e) {
            e.printStackTrace();
        }
    }
}

package com.sjsq.main;
import com.sjsq.entity.Email;
import static com.sjsq.util.SendMail.sendMail;
/**
 * 主函数
 */
public class Main {
    // 测试
    public static void main(String[] args) {
        String subject = "Java测试邮件";
        String concent = "测试内容！";
        String address = "helongqiang@qq.com";
        Email email = new Email();
        email.setSubject(subject);
        email.setConetent(concent);
        sendMail(email,address);
    }
}