版权声明：本文为博主原创文章，未经博主允许不得转载。 https://blog.csdn.net/qwerty_4/article/details/81780761
一、关于发送邮件的原理
这篇博文 https://www.cnblogs.com/whgk/p/6506027.html
二、发送邮件工具类
这里用到guava工具类，所以多加了个guava依赖:
<dependency>
<groupId>javax.mail</groupId>
<artifactId>mail</artifactId>
<version>1.4</version>
</dependency>
<dependency>
<groupId>com.google.guava</groupId>
<artifactId>guava</artifactId>
<version>18.0</version>
</dependency>
发送邮件工具类：
import com.google.common.base.Joiner;
import com.google.common.base.Strings;
import javax.activation.DataHandler;
import javax.activation.FileDataSource;
import javax.mail.*;
import javax.mail.internet.*;
import java.util.ArrayList;
import java.util.List;
import java.util.Properties;
/**
* @classDesc: (发送邮邮件 建造者模式校验发件人、收件人邮箱等)
* @Author: S_even_77
* @createTime: Created in 13:38 2018/8/17
*/
public class EmailInfo {
//抄送方式默认是抄送
public enum RecipientType {
CC, BCC
}
//smtp服务器地址
private String host;
//发件邮箱
private String from;
//发件邮箱密码
private String passowrd;
//收件邮箱
private List<String> toList;
//主题
private String subject;
//邮件内容
private String content;
//邮件附件
private List<String> attachFileList;
//抄送方式
private RecipientType recipientType;
//抄送人列表
private List<String> recipientList;
private EmailInfo(Builder builder) {
this.host = builder.host;
this.from = builder.from;
this.passowrd = builder.passowrd;
this.toList = builder.toList;
this.subject = builder.subject;
this.content = builder.content;
this.attachFileList = builder.attachFileList;
this.recipientType = builder.recipientType;
this.recipientList = builder.recipientList;
}
public static class Builder {
//smtp服务器地址
private String host;
//发件邮箱
private String from;
//发件邮箱密码
private String passowrd;
//收件邮箱
private List<String> toList;
//主题
private String subject;
//邮件内容
private String content;
//邮件附件
private List<String> attachFileList;
//抄送方式
private RecipientType recipientType;
//抄送人列表
private List<String> recipientList;
public Builder setHost(String host) {
this.host = host;
return this;
}
public Builder setFrom(String from) {
this.from = from;
return this;
}
public Builder setPassowrd(String passowrd) {
this.passowrd = passowrd;
return this;
}
public Builder addTo(String to) {
if (this.toList == null) {
this.toList = new ArrayList<>();
}
this.toList.add(to);
return this;
}
public Builder setSubject(String subject) {
this.subject = subject;
return this;
}
public Builder setContent(String content) {
this.content = content;
return this;
}
public Builder addAttachFile(String attachFile) {
if (this.attachFileList == null) {
this.attachFileList = new ArrayList<>();
}
this.attachFileList.add(attachFile);
return this;
}
public Builder setRecipientType(RecipientType recipientType) {
this.recipientType = recipientType;
return this;
}
public Builder addRecipient(String recipient) {
if (this.recipientList == null) {
this.recipientList = new ArrayList<>();
}
this.recipientList.add(recipient);
return this;
}
public EmailInfo build() throws Exception {
if (Strings.isNullOrEmpty(host)) {
throw new RuntimeException("未设置smtp服务器地址");
}
if (Strings.isNullOrEmpty(from)) {
throw new RuntimeException("未设置发件邮箱");
}
if (Strings.isNullOrEmpty(passowrd)) {
throw new RuntimeException("未设置发件邮箱密码");
}
if (toList == null || toList.isEmpty()) {
throw new RuntimeException("未设置收件邮箱");
}
if (subject == null) {
subject = "";
}
if (Strings.isNullOrEmpty(content)) {
throw new RuntimeException("未设置邮件内容");
}
if (attachFileList == null) {
attachFileList = new ArrayList<>();
}
if (recipientType == null) {
this.recipientType = RecipientType.CC;
}
if (recipientList == null) {
recipientList = new ArrayList<>();
}
return new EmailInfo(this);
}
}
public void sendEmail() throws Exception {
//获取连接 1.获得连接 确定连接位置
Properties properties = new Properties();
//获取邮箱的smtp服务器的地址
properties.setProperty("mail.host", host);
//是否进行权限验证
properties.setProperty("mail.smtp.auth", "true");
properties.put("mail.transport.protocol", "smtp");
//修改端口号
//SSLSocketFactory类的端口
properties.put("mail.smtp.socketFactory.port", "465");
//SSLSocketFactory类
properties.put("mail.smtp.socketFactory.class", "javax.net.ssl.SSLSocketFactory");
properties.put("mail.smtp.auth", "true");
//网易提供的ssl加密端口,QQ邮箱也是该端口
properties.put("mail.smtp.port", "465");
//获取连接 2.确定权限(账号和密码)
Authenticator authenticator = new Authenticator() {
@Override
protected PasswordAuthentication getPasswordAuthentication() {
return new PasswordAuthentication(from, passowrd);
}
};
//1.获取连接(连接地址(smtp服务器的地址 + 权限验证) + 确定权限)
Session session = Session.getDefaultInstance(properties,authenticator);
//2.创建消息(发件人 + 收件人 + 主题 + 内容)
Message message = new MimeMessage(session);
//2.1发件人
message.setFrom(new InternetAddress(from));
/**
* 第一个参数:
* Message.RecipientType.TO 代表收件人
* RecipientType.CC 抄送
* RecipientType.BCC 暗送
* 关于抄送暗送
* A给B发送邮件, A觉得有必要让C也看看其内容,就在给B发送邮件时候将邮件内容抄送给C,
* 这时候B知道A给C抄送过该邮件; 如果是暗送(密送),那B就不知道A也给C发送过该邮件
* 第二个参数:
* 也可以是数组, 群发
*/
//2.2收件人
message.setRecipients(Message.RecipientType.TO, new InternetAddress().parse(Joiner.on(",").skipNulls().join(toList)));
//2.3抄送人
if (recipientType == RecipientType.CC) {
message.addRecipients(Message.RecipientType.CC, new InternetAddress().parse(Joiner.on(",").skipNulls().join(recipientList)));
}else {
message.addRecipients(Message.RecipientType.BCC, new InternetAddress().parse(Joiner.on(",").skipNulls().join(recipientList)));
}
//2.4主题
message.setSubject(subject);
//2.5内容
Multipart multipart = new MimeMultipart();
BodyPart bodyPart = new MimeBodyPart();
bodyPart.setContent(content, "text/html;charset=UTF-8");
multipart.addBodyPart(bodyPart);
//2.6附件
for (String attach : attachFileList) {
BodyPart body = new MimeBodyPart();
FileDataSource fileDataSource = new FileDataSource(attach);
body.setDataHandler(new DataHandler(fileDataSource));
body.setFileName(MimeUtility.encodeText(fileDataSource.getName()));
multipart.addBodyPart(body);
}
message.setContent(multipart);
//3.发送消息
Transport.send(message);
}
}
三、测试类
/**
* @classDesc: ()
* @Author: S_even_77
* @createTime: Created in 13:34 2018/8/17
*/
public class EmailUtil {
public static void main(String[] args) {
try {
EmailInfo emailInfo = new EmailInfo.Builder()
.setHost("XX")
.setFrom("XXX")
.setPassowrd("XXX")
.setContent("hahaha")
.addTo("XXX")
.addTo("XXX")
.setSubject("hahah")
.setRecipientType(EmailInfo.RecipientType.BCC)
.addAttachFile("XXX")
.addRecipient("XXX")
.build();
emailInfo.sendEmail();
} catch (Exception e) {
e.printStackTrace();
}
}
}
四、注意
阿里云服务器禁掉了25端口，这里需要修改成加密端口号。