在使用spring-boot-starter mail时出现mailHealthContributor异常

Question

我刚刚将依赖项compile 'org.springframework.boot:spring-boot-starter-mail'添加到我的build.gradle中

...
    implementation 'org.springframework.boot:spring-boot-starter-actuator'
    implementation 'org.springframework.boot:spring-boot-starter-data-jpa'
    implementation 'org.springframework.boot:spring-boot-starter-validation'
    implementation('org.springframework.boot:spring-boot-starter-web') {
        exclude group: 'org.springframework.boot', module: 'spring-boot-starter-tomcat'
    }
    implementation 'org.springframework.boot:spring-boot-starter-jetty'
    compile 'org.springframework.boot:spring-boot-starter-security'
    compile 'org.springframework.boot:spring-boot-starter-mail'
    compile 'org.springframework.security:spring-security-jwt:1.0.11.RELEASE'
    compile 'org.springframework.security.oauth:spring-security-oauth2:2.3.7.RELEASE'
...

然后我创建了一个使用JavaMailSender的类

@Component
public class AdminEmailService {
    @Autowired
    private JavaMailSender javaMailSender;

    public void sendSimpleMessage(String subject, String text) {
        final SimpleMailMessage message = createMessage(subject, text);
        javaMailSender.send(message);
    }

    ...
}

但是这导致了mailhealthContributor和healthContributorRegistry的异常。

Caused by: org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'webMvcRequestHandlerProvider' defined in URL [jar:file:/C:/Users/xxxx/.gradle/caches/modules-2/files-2.1/io.springfox/springfox-spring-web/2.9.2/ed2ed714a6cba8804d00f80f0534901e4c7a3211/springfox-spring-web-2.9.2.jar!/springfox/documentation/spring/web/plugins/WebMvcRequestHandlerProvider.class]: Unsatisfied dependency expressed through constructor parameter 1; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'webEndpointServletHandlerMapping' defined in class path resource [org/springframework/boot/actuate/autoconfigure/endpoint/web/servlet/WebMvcEndpointManagementContextConfiguration.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.springframework.boot.actuate.endpoint.web.servlet.WebMvcEndpointHandlerMapping]: Factory method 'webEndpointServletHandlerMapping' threw exception; nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'healthEndpoint' defined in class path resource [org/springframework/boot/actuate/autoconfigure/health/HealthEndpointConfiguration.class]: Unsatisfied dependency expressed through method 'healthEndpoint' parameter 0; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'healthContributorRegistry' defined in class path resource [org/springframework/boot/actuate/autoconfigure/health/HealthEndpointConfiguration.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.springframework.boot.actuate.health.HealthContributorRegistry]: Factory method 'healthContributorRegistry' threw exception; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'mailHealthContributor' defined in class path resource [org/springframework/boot/actuate/autoconfigure/mail/MailHealthContributorAutoConfiguration.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.springframework.boot.actuate.health.HealthContributor]: Factory method 'mailHealthContributor' threw exception; nested exception is java.lang.IllegalArgumentException: Beans must not be empty
    at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:797) ~[spring-beans-5.2.8.RELEASE.jar:5.2.8.RELEASE]
    at org.springframework.beans.factory.support.ConstructorResolver.autowireConstructor(ConstructorResolver.java:227) ~[spring-beans-5.2.8.RELEASE.jar:5.2.8.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.autowireConstructor(AbstractAutowireCapableBeanFactory.java:1356) ~[spring-beans-5.2.8.RELEASE.jar:5.2.8.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1203) ~[spring-beans-5.2.8.RELEASE.jar:5.2.8.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:556) ~[spring-beans-5.2.8.RELEASE.jar:5.2.8.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:516) ~[spring-beans-5.2.8.RELEASE.jar:5.2.8.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:324) ~[spring-beans-5.2.8.RELEASE.jar:5.2.8.RELEASE]
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:226) ~[spring-beans-5.2.8.RELEASE.jar:5.2.8.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:322) ~[spring-beans-5.2.8.RELEASE.jar:5.2.8.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:202) ~[spring-beans-5.2.8.RELEASE.jar:5.2.8.RELEASE]
    at org.springframework.beans.factory.config.DependencyDescriptor.resolveCandidate(DependencyDescriptor.java:276) ~[spring-beans-5.2.8.RELEASE.jar:5.2.8.RELEASE]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.addCandidateEntry(DefaultListableBeanFactory.java:1525) ~[spring-beans-5.2.8.RELEASE.jar:5.2.8.RELEASE]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.findAutowireCandidates(DefaultListableBeanFactory.java:1489) ~[spring-beans-5.2.8.RELEASE.jar:5.2.8.RELEASE]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveMultipleBeans(DefaultListableBeanFactory.java:1378) ~[spring-beans-5.2.8.RELEASE.jar:5.2.8.RELEASE]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1265) ~[spring-beans-5.2.8.RELEASE.jar:5.2.8.RELEASE]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1227) ~[spring-beans-5.2.8.RELEASE.jar:5.2.8.RELEASE]
    at org.springframework.beans.factory.support.ConstructorResolver.resolveAutowiredArgument(ConstructorResolver.java:884) ~[spring-beans-5.2.8.RELEASE.jar:5.2.8.RELEASE]
    at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:788) ~[spring-beans-5.2.8.RELEASE.jar:5.2.8.RELEASE]
    ... 69 common frames omitted

我怎么才能解决这个问题？没有依赖关系吗？

Answer 1

我通过定义一个JavaMailSender bean来解决这个问题：

@Configuration
public class EmailConfig {

    @Bean("emailsender") // important!
    public JavaMailSender getJavaMailSender(@Value("${spring.mail.host}") String host,
            @Value("${spring.mail.port}") int port) {
        final JavaMailSenderImpl javaMailSender = new JavaMailSenderImpl();
        javaMailSender.setHost(host);
        javaMailSender.setPort(port);
        return javaMailSender;
    }
}

给它注射合格的药物：

    @Autowired
    @Qualifier("emailsender")
    private JavaMailSender javaMailSender;

但是，难道没有不定义自己的bean的解决方案吗？