发送邮件的功能有时在业务中还是需要使用到的,比如订单方面的业务,用户下单后需要给用户发送一个订单相关的邮件;又或者是某些系统在业务层来集成预警功能,出现问题时及时给开发和运维发送预警邮件。那么,接下来将讲一下在springboot项目中邮件发送功能的集成与其简单的使用。
依赖引入
首先,在POM文件中加入如下依赖:
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-mail</artifactId>
</dependency>
springboot为我们提供了这个邮件相关的stater,旨在更方便引入依赖和进行配置。spring-boot-starter-mail
主要包含了如下与邮件相关的依赖包:
- org.springframework:spring-context-support
- org.springframework.mail
- com.sun.mail.javax.email
其中,spring的mail是在javax的mail上做了更抽象的封装,方便我们使用。仔细查看源码,就会观察到如下一些关键的类:
- 邮件发送:MailSender -> JavaMailSender -> JavaMailSenderImpl
- 邮件消息包装:MailMessasge, SimpleMailMessage, MimeMailMessage
- 邮件消息的helper:MimeMessageHelper
配置设置
在application.yml中加入邮件相关的配置,项目启动后便会在spring的bean容器中注入MailSender和JavaMailSender(他们有共同的实现类JavaMailSenderImpl),之后便可以在代码中使用相关的方法实现发送邮件的功能了。配置信息如下:
spring:
mail:
host: smtp.163.com
port: 25
username: lazycece@163.com
password: 客户端授权码
使用案例
依赖已引入,亦完成mail相关的配置设置,接下来就该来实现发送邮件的功能了。邮件的的发送涉及如下相关:
- 简单邮件内容发送
- MIME(Multipurpose Internet Mail Extensions)多用途互联网邮件扩展类型的邮件类型
首先,来定义一个简单的实体(使用了Lombok,详见Lombok插件讲解),表示邮件相关的信息,如下:
@Data
@Builder
@NoArgsConstructor
@AllArgsConstructor
public class Message {
/**
* 收件人
*/
private String to;
/**
* 发件人
*/
private String from;
/**
* 邮件主题
*/
private String subject;
/**
* 邮件内容
*/
private String text;
/**
* 附件
*/
private String attachment;
/**
* 嵌入资源
*/
private String inlineResource;
}
这里只定义了常规内容,抄送CC(Carbon Copy),加密抄送BCC(Blind Carbon Copy)就不再说明了。
邮件内容的包装可以是SimpleMailMessage
,又或者是MimeMailMessage
,顾名思义便能想到这两个类的用途,接下来便来说明简单邮件内容的发送、发送附件和内容内嵌资源(图片,音频)等功能。
简单内容发送
使用SimpleMailMessage
来包装邮件信息,使用MailSender
来执行发送事件,代码如下:
public void sendSimpleMessage(Message message) {
SimpleMailMessage msg = new SimpleMailMessage();
msg.setFrom(message.getFrom());
msg.setTo(message.getTo());
msg.setSubject(message.getSubject());
msg.setText(message.getText());
mailSender.send(msg);
}
使用MimeMessagePreparator
来包装MimeMailMessage
邮件信息,使用JavaMailSender
来执行发送事件,代码如下:
public void sendPreparatorMimeMessage(Message message) {
MimeMessagePreparator preparator = mimeMessage -> {
mimeMessage.setFrom(message.getFrom());
mimeMessage.setRecipients(javax.mail.Message.RecipientType.TO, message.getTo());
mimeMessage.setSubject(message.getSubject());
mimeMessage.setText(message.getText());
};
javaMailSender.send(preparator);
}
使用MimeMessageHelper
来包装MimeMailMessage
邮件信息,使用JavaMailSender
来执行发送事件,代码如下:
public void sendBasicMimeMessage(Message message) {
MimeMailMessage mimeMailMessage = new MimeMailMessage(javaMailSender.createMimeMessage());
try {
MimeMessageHelper helper = mimeMailMessage.getMimeMessageHelper();
helper.setTo(message.getTo());
helper.setFrom(message.getFrom());
helper.setSubject(message.getSubject());
helper.setText(message.getText());
} catch (MessagingException e) {
log.error("build mail message error");
}
javaMailSender.send(mimeMailMessage.getMimeMessage());
}
发送附件内容
附件功能只能使用MimeMailMessage
进行邮件信息包装,可以添加单个邮件,多个邮件,这里以单个邮件为例,代码如下:
public void sendAttachmentsMimeMessage(Message message) {
MimeMailMessage mimeMailMessage = new MimeMailMessage(javaMailSender.createMimeMessage());
try {
MimeMessageHelper helper = new MimeMessageHelper(mimeMailMessage.getMimeMessage(), true);
helper.setFrom(message.getFrom());
helper.setTo(message.getTo());
helper.setSubject(message.getSubject());
helper.setText(message.getText());
FileSystemResource file = new FileSystemResource(new File(message.getAttachment()));
helper.addAttachment(file.getFilename(), file);
} catch (MessagingException e) {
log.error("build mail message error");
}
javaMailSender.send(mimeMailMessage.getMimeMessage());
}
嵌入资源内容
嵌入资源功能亦只能使用MimeMailMessage
进行邮件信息包装,这里以在邮件内容中嵌入一张图片为例,“resource1234”是资源的id,确保在邮件嵌入资源中唯一,才能正确引入到html。代码如下:
public void sendInlineImageMimeMessage(Message message) {
MimeMailMessage mimeMailMessage = new MimeMailMessage(javaMailSender.createMimeMessage());
try {
MimeMessageHelper helper = new MimeMessageHelper(mimeMailMessage.getMimeMessage(), true);
helper.setFrom(message.getFrom());
helper.setTo(message.getTo());
helper.setSubject(message.getSubject());
String html = "<html><body><img src='cid:resource1234'></body></html>";
helper.setText(message.getText(), html);
FileSystemResource resource = new FileSystemResource(new File(message.getInlineResource()));
helper.addInline("resource1234", resource);
} catch (MessagingException e) {
log.error("build mail message error");
}
javaMailSender.send(mimeMailMessage.getMimeMessage());
}
测试验证
下面贴出单元测试代码:
package com.lazycece.sbac.mail.manager;
import com.lazycece.sbac.mail.entity.Message;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringRunner;
import javax.annotation.Resource;
/**
* @author lazycece
* @date 2019/5/21
*/
@SpringBootTest
@RunWith(SpringRunner.class)
public class MailManagerTest {
@Resource
private MailManager mailManager;
private Message.MessageBuilder commonMail() {
return Message.builder()
.from("lazycece@163.com")
.to("lazycece@163.com")
.subject("你好");
}
@Test
public void testSendSimpleMessage() {
Message message = commonMail()
.text("Hello, simple message ! ")
.build();
mailManager.sendSimpleMessage(message);
}
@Test
public void testSendPreparatorMimeMessage() {
Message message = commonMail()
.text("Hello, preparator mime message ! ")
.build();
mailManager.sendPreparatorMimeMessage(message);
}
@Test
public void sendBasicMimeMessage() {
Message message = commonMail()
.text("Hello, basic mime email ! ")
.build();
mailManager.sendBasicMimeMessage(message);
}
@Test
public void sendAttachmentsMimeMessage() {
Message message = commonMail()
.text("Hello, attachment mime email ! ")
.attachment("/home/lazycece/下载/temp.png")
.build();
mailManager.sendAttachmentsMimeMessage(message);
}
@Test
public void sendInlineImageMimeMessage() {
Message message = commonMail()
.text("Hello, inline image mime email ! ")
.inlineResource("/home/lazycece/下载/temp.png")
.build();
mailManager.sendInlineImageMimeMessage(message);
}
}
案例源码
案例源码地址:https://github.com/lazycece/springboot-actual-combat/tree/master/springboot-ac-email