发送电子邮件
通过使用Spring Boot RESTful Web服务，您可以使用Gmail传输层安全性发送电子邮件。在本章中，让我们详细了解如何使用此功能。
首先，我们需要在构建配置文件中添加Spring Boot Starter Mail依赖项。
Maven用户可以将以下依赖项添加到pom.xml文件中。
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-mail</artifactId>
</dependency>
对于Gradle用户，在build.gradle文件中添加以下依赖项。
implementation 'org.springframework.boot:spring-boot-starter-mail'
下面给出了主要的Spring Boot应用程序类文件的代码-
package com.jc2182.emailapp;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
@SpringBootApplication
public class EmailappApplication {
public static void main(String[] args) {
SpringApplication.run(EmailappApplication.class, args);
}
}
您可以编写一个简单的Rest API，以在Rest Controller类文件中发送给电子邮件，如图所示。
package com.jc2182.emailapp;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
@RestController
public class EmailController {
@RequestMapping(value = "/sendemail")
public String sendEmail() {
return "Email sent successfully";
}
}
您可以编写一种发送带有附件的电子邮件的方法。定义mail.smtp属性和使用的PasswordAuthentication。
private void sendmail() throws AddressException, MessagingException, IOException {
Properties props = new Properties();
props.put("mail.smtp.auth", "true");
props.put("mail.smtp.starttls.enable", "true");
props.put("mail.smtp.host", "smtp.gmail.com");
props.put("mail.smtp.port", "587");
Session session = Session.getInstance(props, new javax.mail.Authenticator() {
protected PasswordAuthentication getPasswordAuthentication() {
return new PasswordAuthentication("jc2182@gmail.com", "");
}
});
Message msg = new MimeMessage(session);
msg.setFrom(new InternetAddress("jc2182@gmail.com", false));
msg.setRecipients(Message.RecipientType.TO, InternetAddress.parse("jc2182@gmail.com"));
msg.setSubject("Tutorials point email");
msg.setContent("Tutorials point email", "text/html");
msg.setSentDate(new Date());
MimeBodyPart messageBodyPart = new MimeBodyPart();
messageBodyPart.setContent("Tutorials point email", "text/html");
Multipart multipart = new MimeMultipart();
multipart.addBodyPart(messageBodyPart);
MimeBodyPart attachPart = new MimeBodyPart();
attachPart.attachFile("/var/tmp/image19.png");
multipart.addBodyPart(attachPart);
msg.setContent(multipart);
Transport.send(msg);
}
现在，从Rest API调用上述sendmail()方法，如下所示：
@RequestMapping(value = "/sendemail")
public String sendEmail() throws AddressException, MessagingException, IOException {
sendmail();
return "Email sent successfully";
}
注意 -发送电子邮件之前，请先在Gmail帐户设置中打开允许安全性较低的应用程序。
完整的构建配置文件在下面给出
Maven – pom.xml
<?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>2.3.0.BUILD-SNAPSHOT</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>com.jc2182</groupId>
<artifactId>demo</artifactId>
<version>0.0.1-SNAPSHOT</version>
<!-- <packaging>war</packaging> -->
<name>demo</name>
<description>Demo project for Spring Boot</description>
<properties>
<java.version>1.8</java.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-mail</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
<exclusions>
<exclusion>
<groupId>org.junit.vintage</groupId>
<artifactId>junit-vintage-engine</artifactId>
</exclusion>
</exclusions>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
<repositories>
<repository>
<id>spring-milestones</id>
<name>Spring Milestones</name>
<url>https://repo.spring.io/milestone</url>
</repository>
<repository>
<id>spring-snapshots</id>
<name>Spring Snapshots</name>
<url>https://repo.spring.io/snapshot</url>
<snapshots>
<enabled>true</enabled>
</snapshots>
</repository>
</repositories>
<pluginRepositories>
<pluginRepository>
<id>spring-milestones</id>
<name>Spring Milestones</name>
<url>https://repo.spring.io/milestone</url>
</pluginRepository>
<pluginRepository>
<id>spring-snapshots</id>
<name>Spring Snapshots</name>
<url>https://repo.spring.io/snapshot</url>
<snapshots>
<enabled>true</enabled>
</snapshots>
</pluginRepository>
</pluginRepositories>
</project>
Gradle – build.gradle
plugins {
id 'org.springframework.boot' version '2.3.0.BUILD-SNAPSHOT'
id 'io.spring.dependency-management' version '1.0.9.RELEASE'
id 'java'
}
group = 'com.jc2182'
version = '0.0.1-SNAPSHOT'
sourceCompatibility = '1.8'
repositories {
mavenCentral()
maven { url 'https://repo.spring.io/milestone' }
maven { url 'https://repo.spring.io/snapshot' }
}
dependencies {
implementation 'org.springframework.boot:spring-boot-starter-web'
implementation 'org.springframework.boot:spring-boot-starter-mail'
testImplementation('org.springframework.boot:spring-boot-starter-test') {
exclude group: 'org.junit.vintage', module: 'junit-vintage-engine'
}
}
test {
useJUnitPlatform()
}
您可以创建一个可执行的JAR文件，并使用Maven或Gradle命令运行Spring Boot应用程序-
对于Maven，您可以使用以下命令-
在“BUILD SUCCESS”之后，您可以在target目录下找到JAR文件。
对于Gradle，您可以使用以下命令-
在“BUILD SUCCESSFUL”之后，您可以在build/libs目录下找到JAR文件。
您可以使用以下命令运行JAR文件-
现在，该应用程序已在Tomcat端口8080上启动，
现在，在Web浏览器中访问URL - http://localhost:8080/sendemail，您将收到一封电子邮件。
