spring boot学习第十一篇:发邮件

1、pom.xml文件内容如下（是我所有学习内容需要的，不再单独分出来，包不会冲突）：

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd"><modelVersion>4.0.0</modelVersion><parent><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-parent</artifactId><version>2.6.4</version><relativePath/> <!-- lookup parent from repository --></parent><groupId>com.hm-email</groupId><artifactId>hm-email</artifactId><version>0.0.1-SNAPSHOT</version><name>hm-email</name><description>hm-email</description><properties><java.version>8</java.version><druid.version>1.2.8</druid.version><log4jdbc.version>1.16</log4jdbc.version><es.version>7.9.2</es.version></properties><dependencies><!-- druid数据源驱动 --><dependency><groupId>com.alibaba</groupId><artifactId>druid-spring-boot-starter</artifactId><version>${druid.version}</version></dependency><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter</artifactId></dependency><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-test</artifactId><scope>test</scope></dependency><!-- mybatis --><dependency><groupId>com.baomidou</groupId><artifactId>mybatis-plus-boot-starter</artifactId><version>3.5.3.1</version></dependency><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-web</artifactId></dependency><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-test</artifactId></dependency><dependency><groupId>org.projectlombok</groupId><artifactId>lombok</artifactId><optional>true</optional></dependency><!--Mysql依赖包--><dependency><groupId>mysql</groupId><artifactId>mysql-connector-java</artifactId><scope>runtime</scope></dependency><!--lombok插件--><dependency><groupId>org.projectlombok</groupId><artifactId>lombok</artifactId><optional>true</optional></dependency><!--监控sql日志--><dependency><groupId>org.bgee.log4jdbc-log4j2</groupId><artifactId>log4jdbc-log4j2-jdbc4.1</artifactId><version>${log4jdbc.version}</version></dependency><dependency><groupId>com.alibaba</groupId><artifactId>fastjson</artifactId><version>1.2.9</version></dependency><dependency><groupId>redis.clients</groupId><artifactId>jedis</artifactId></dependency><dependency><groupId>org.apache.kafka</groupId><artifactId>kafka-clients</artifactId></dependency><dependency><groupId>org.springframework.kafka</groupId><artifactId>spring-kafka</artifactId></dependency><!-- high client--><dependency><groupId>org.elasticsearch.client</groupId><artifactId>elasticsearch-rest-high-level-client</artifactId><version>${es.version}</version><exclusions><exclusion><groupId>org.elasticsearch</groupId><artifactId>elasticsearch</artifactId></exclusion><exclusion><groupId>org.elasticsearch.client</groupId><artifactId>elasticsearch-rest-client</artifactId></exclusion></exclusions></dependency><!-- rest-high-level-client 依赖如下2个jar --><dependency><groupId>org.elasticsearch</groupId><artifactId>elasticsearch</artifactId><version>${es.version}</version></dependency><dependency><groupId>org.elasticsearch.client</groupId><artifactId>elasticsearch-rest-client</artifactId><version>${es.version}</version></dependency><dependency><groupId>junit</groupId><artifactId>junit</artifactId></dependency><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-data-mongodb</artifactId></dependency><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-security</artifactId></dependency><dependency><groupId>org.springframework.security.oauth.boot</groupId><artifactId>spring-security-oauth2-autoconfigure</artifactId><version>2.4.0</version></dependency><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-mail</artifactId></dependency><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-thymeleaf</artifactId></dependency></dependencies><build><plugins><plugin><groupId>org.springframework.boot</groupId><artifactId>spring-boot-maven-plugin</artifactId></plugin></plugins></build></project>

2、application.yml内容如下：

server:port: 8081servlet.context-path: /#配置数据源
spring:datasource:druid:db-type: com.alibaba.druid.pool.DruidDataSourcedriverClassName: net.sf.log4jdbc.sql.jdbcapi.DriverSpyurl: jdbc:log4jdbc:mysql://${DB_HOST:localhost}:${DB_PORT:3306}/${DB_NAME:eladmin}?serverTimezone=Asia/Shanghai&characterEncoding=utf8&useSSL=falseusername: ${DB_USER:root}password: ${DB_PWD:demo}redis:host: localhostport: 6379password: demodatabase: 10data:mongodb:host: 43.138.0.199port: 27017username: hmblogspassword: demodatabase: hmblogsauthentication-database: adminmail:host: smtp.163.com # smtp地址，开通的时候会显示username: [e-mail] # 你的邮箱账号password: demo # 你的邮箱授权码default-encoding: UTF-8properties:mail:smtp:socketFactory:class: javax.net.ssl.SSLSocketFactoryauth: falsestarttls:enable: falsedebug: trueprotocol: smtpes:host: 43.138.0.199port: 9200scheme: httpuser: elasticpassword: demo

3、BackendApplication内容如下：

package com.hmblogs.backend;import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;@SpringBootApplication
public class BackendApplication {public static void main(String[] args) {SpringApplication.run(BackendApplication.class, args);}}

4、EmailService文件内容如下：

package com.hmblogs.backend.service;import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.mail.SimpleMailMessage;
import org.springframework.mail.javamail.JavaMailSender;
import org.springframework.mail.javamail.MimeMessageHelper;
import org.springframework.stereotype.Service;import javax.mail.MessagingException;
import javax.mail.internet.MimeMessage;
import java.io.File;@Service
@Slf4j
public class EmailService {@Autowiredprivate JavaMailSender mailSender;@Value("${spring.mail.username}")private String username;/*** 使用thymeleaf模板* @param to* @param subject* @param context*/public void sendHtmlMail(String to ,String subject,String context){try {MimeMessage mimeMessage = mailSender.createMimeMessage();MimeMessageHelper mimeMessageHelper = new MimeMessageHelper(mimeMessage, true);mimeMessageHelper.setFrom(username);mimeMessageHelper.setTo(to);mimeMessageHelper.setText(context);mimeMessageHelper.setSubject(subject);mailSender.send(mimeMessage);} catch (MessagingException e) {e.printStackTrace();}}/*** 发送文本邮件** @param to      收件人地址* @param subject 邮件主题* @param content 邮件内容* @param cc      抄送地址*/public  void sendSimpleMail(String to, String subject, String content, String... cc) {SimpleMailMessage message = new SimpleMailMessage();message.setFrom(username);message.setTo(to);message.setSubject(subject);message.setText(content);if (cc!=null) {message.setCc(cc);}mailSender.send(message);}/*** 发送带附件的邮件** @param to       收件人地址* @param subject  邮件主题* @param content  邮件内容* @param filePath 附件地址* @param cc       抄送地址*/public  void sendAttachmentsMail(String to, String subject, String content, String filePath, String... cc) {try {MimeMessage message = mailSender.createMimeMessage();MimeMessageHelper helper = new MimeMessageHelper(message, true,"UTF-8");helper.setFrom(username);helper.setTo(to);helper.setSubject(subject);helper.setText(content, true);if (cc!=null) {helper.setCc(cc);}File file = new File(filePath);String fileName = filePath.substring(filePath.lastIndexOf(File.separator));helper.addAttachment(fileName, file);mailSender.send(message);} catch (MessagingException e) {log.error("发送邮件失败,收件人:{}", to, e);}}
}

5、EmailServiceTest测试类内容如下：

package com.hmblogs.backend.util;import com.hmblogs.backend.BackendApplication;
import com.hmblogs.backend.service.EmailService;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
import org.thymeleaf.TemplateEngine;
import org.thymeleaf.context.Context;import javax.annotation.Resource;@RunWith(SpringJUnit4ClassRunner.class)
@SpringBootTest(classes={BackendApplication.class, EmailServiceTest.class})
public class EmailServiceTest {@Resourceprivate EmailService emailService;private static final String to = "[e-mail]";@Testpublic void test(){emailService.sendSimpleMail(to,"简单测试22","简单测试");}@Testpublic void testWithAttachment(){emailService.sendAttachmentsMail(to,"附件测试22","附件测试","E:\\fileTest.txt");}@AutowiredTemplateEngine templateEngine;@Testpublic void sendHtmlMailThymeleaf(){Context context = new Context();context.setVariable("username","cyc");String mail = templateEngine.process("mailtemplate.html",context);emailService.sendHtmlMail(to,"恭喜22！",mail);}
}

启动服务，执行该方法，报错如下：

org.springframework.mail.MailSendException: Mail server connection failed; nested exception is javax.mail.MessagingException: Could not convert socket to TLS;nested exception is:javax.net.ssl.SSLHandshakeException: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target. Failed messages: javax.mail.MessagingException: Could not convert socket to TLS;nested exception is:javax.net.ssl.SSLHandshakeException: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
; message exception details (1) are:
Failed message 1:
javax.mail.MessagingException: Could not convert socket to TLS;nested exception is:javax.net.ssl.SSLHandshakeException: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested targetat com.sun.mail.smtp.SMTPTransport.startTLS(SMTPTransport.java:2140)at com.sun.mail.smtp.SMTPTransport.protocolConnect(SMTPTransport.java:734)at javax.mail.Service.connect(Service.java:342)at org.springframework.mail.javamail.JavaMailSenderImpl.connectTransport(JavaMailSenderImpl.java:518)at org.springframework.mail.javamail.JavaMailSenderImpl.doSend(JavaMailSenderImpl.java:437)at org.springframework.mail.javamail.JavaMailSenderImpl.send(JavaMailSenderImpl.java:323)at org.springframework.mail.javamail.JavaMailSenderImpl.send(JavaMailSenderImpl.java:312)at com.hmblogs.backend.service.EmailService.sendSimpleMail(EmailService.java:42)at com.hmblogs.backend.util.EmailServiceTest.test(EmailServiceTest.java:21)at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)at java.lang.reflect.Method.invoke(Method.java:498)at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:59)at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:56)at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)at org.springframework.test.context.junit4.statements.RunBeforeTestExecutionCallbacks.evaluate(RunBeforeTestExecutionCallbacks.java:74)at org.springframework.test.context.junit4.statements.RunAfterTestExecutionCallbacks.evaluate(RunAfterTestExecutionCallbacks.java:84)at org.springframework.test.context.junit4.statements.RunBeforeTestMethodCallbacks.evaluate(RunBeforeTestMethodCallbacks.java:75)at org.springframework.test.context.junit4.statements.RunAfterTestMethodCallbacks.evaluate(RunAfterTestMethodCallbacks.java:86)at org.springframework.test.context.junit4.statements.SpringRepeat.evaluate(SpringRepeat.java:84)at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:366)at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:251)at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:97)at org.junit.runners.ParentRunner$4.run(ParentRunner.java:331)at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:79)at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:329)at org.junit.runners.ParentRunner.access$100(ParentRunner.java:66)at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:293)at org.springframework.test.context.junit4.statements.RunBeforeTestClassCallbacks.evaluate(RunBeforeTestClassCallbacks.java:61)at org.springframework.test.context.junit4.statements.RunAfterTestClassCallbacks.evaluate(RunAfterTestClassCallbacks.java:70)at org.junit.runners.ParentRunner$3.evaluate(ParentRunner.java:306)at org.junit.runners.ParentRunner.run(ParentRunner.java:413)at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.run(SpringJUnit4ClassRunner.java:190)at org.junit.runner.JUnitCore.run(JUnitCore.java:137)at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:69)at com.intellij.rt.junit.IdeaTestRunner$Repeater$1.execute(IdeaTestRunner.java:38)at com.intellij.rt.execution.junit.TestsRepeater.repeat(TestsRepeater.java:11)at com.intellij.rt.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:35)at com.intellij.rt.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:232)at com.intellij.rt.junit.JUnitStarter.main(JUnitStarter.java:55)
Caused by: javax.net.ssl.SSLHandshakeException: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested targetat sun.security.ssl.Alerts.getSSLException(Alerts.java:192)at sun.security.ssl.SSLSocketImpl.fatal(SSLSocketImpl.java:1949)at sun.security.ssl.Handshaker.fatalSE(Handshaker.java:302)at sun.security.ssl.Handshaker.fatalSE(Handshaker.java:296)at sun.security.ssl.ClientHandshaker.serverCertificate(ClientHandshaker.java:1514)at sun.security.ssl.ClientHandshaker.processMessage(ClientHandshaker.java:216)at sun.security.ssl.Handshaker.processLoop(Handshaker.java:1026)at sun.security.ssl.Handshaker.process_record(Handshaker.java:961)at sun.security.ssl.SSLSocketImpl.readRecord(SSLSocketImpl.java:1062)at sun.security.ssl.SSLSocketImpl.performInitialHandshake(SSLSocketImpl.java:1375)at sun.security.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:1403)at sun.security.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:1387)at com.sun.mail.util.SocketFetcher.configureSSLSocket(SocketFetcher.java:602)at com.sun.mail.util.SocketFetcher.startTLS(SocketFetcher.java:529)at com.sun.mail.smtp.SMTPTransport.startTLS(SMTPTransport.java:2135)... 41 more
Caused by: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested targetat sun.security.validator.PKIXValidator.doBuild(PKIXValidator.java:387)at sun.security.validator.PKIXValidator.engineValidate(PKIXValidator.java:292)at sun.security.validator.Validator.validate(Validator.java:260)at sun.security.ssl.X509TrustManagerImpl.validate(X509TrustManagerImpl.java:324)at sun.security.ssl.X509TrustManagerImpl.checkTrusted(X509TrustManagerImpl.java:229)at sun.security.ssl.X509TrustManagerImpl.checkServerTrusted(X509TrustManagerImpl.java:124)at sun.security.ssl.ClientHandshaker.serverCertificate(ClientHandshaker.java:1496)... 51 more
Caused by: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested targetat sun.security.provider.certpath.SunCertPathBuilder.build(SunCertPathBuilder.java:141)at sun.security.provider.certpath.SunCertPathBuilder.engineBuild(SunCertPathBuilder.java:126)at java.security.cert.CertPathBuilder.build(CertPathBuilder.java:280)at sun.security.validator.PKIXValidator.doBuild(PKIXValidator.java:382)... 57 more

查了一圈资料，和SSL证书有关的，都不行，最后试着改改配置文件，发现搞好了

目标邮箱收到了如下邮件：

发件邮箱，发的邮件如下：

但是，问题是，模板html没解析出来，非研发同学肯定看不懂邮件内容，

 怎么处理呢？

比对网上的资料，

问题解决了，邮件截图如下：