我利用 Spring JavaMailSender 并实现了一个自定义 MailService,它使用 Thymeleaf 和 Spring JavaMailSender 来提供高级服务方法。这个效果很好。
现在我需要在另一个应用程序中提供相同的功能。因此,我将该服务提取到一个库中,并使用自动配置将其连接到我的应用程序中。
库和应用程序均使用 Spring 版本 3.3.2 和 Java 17。
在我的 POM 库中,我有这些依赖项:
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-autoconfigure-processor</artifactId>
<optional>true</optional>
</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>
我的应用程序取决于我的图书馆:
<dependency>
<groupId>com.acme.library</groupId>
<artifactId>lib-spring-mail</artifactId>
<version>1.0.0-SNAPSHOT</version>
</dependency>
@AutoConfiguration 注解的类如下所示:
@AutoConfiguration(after = { MailSenderAutoConfiguration.class,
ThymeleafAutoConfiguration.class})
@ConditionalOnClass({JavaMailSender.class, TemplateEngine.class})
public class MailAutoConfiguration {
@Autowired
private JavaMailSender mailSender;
@Autowired
private TemplateEngine templateEngine;
@Bean
@ConditionalOnMissingBean
public MailService mailService() {
return new MailService(mailSender, templatingService());
}
@Bean
@ConditionalOnMissingBean
public TemplatingService templatingService() {
return new TemplatingService(templateEngine);
}
}
并且 org.springframework.boot.autoconfigure.AutoConfiguration.imports 文件如下所示:
org.springframework.boot.autoconfigure.mail.MailSenderAutoConfiguration
虽然编译没有问题,但启动应用程序时我收到此错误消息:
Field mailSender in com.acme.library.spring.mail.MailAutoConfiguration required a bean of type 'org.springframework.mail.javamail.JavaMailSender' that could not be found.
The injection point has the following annotations:
- @org.springframework.beans.factory.annotation.Autowired(required=true)
Action:
Consider defining a bean of type 'org.springframework.mail.javamail.JavaMailSender' in your configuration.
底层异常是:
Caused by: org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type 'org.springframework.mail.javamail.JavaMailSender' available: expected at least 1 bean which qualifies as autowire candidate. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)}
at org.springframework.beans.factory.support.DefaultListableBeanFactory.raiseNoMatchingBeanFound(DefaultListableBeanFactory.java:1880) ~[spring-beans-6.1.11.jar:6.1.11]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1406) ~[spring-beans-6.1.11.jar:6.1.11]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1353) ~[spring-beans-6.1.11.jar:6.1.11]
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.resolveFieldValue(AutowiredAnnotationBeanPostProcessor.java:784) ~[spring-beans-6.1.11.jar:6.1.11]
虽然我的应用程序应该将这两个启动器依赖项作为我的库 POM 的传递依赖项找到,但我明确地将它们添加到应用程序的 POM 中。然而,这并没有改变错误
如何在我的库中使用 Spring-Boot 预配置的 JavaMailSender?这可能吗?
您需要在
org.springframework.boot.autoconfigure.AutoConfiguration.imports
文件夹中创建 META-INF/spring
文件。
在里面您需要列出您的配置 FQN。每行一个。