在实现 Groovy 接口的 Groovy 类中，@Autowired 依赖项为空

Question

我正在尝试将属性类注入到基于 Groovy 的类中，但注入的类为空。我确实有另一个属性类被注入到从 Tomcat 的 Filter 接口实现的类中，并且工作正常。

这是我启动 Spring Boot 应用程序时的堆栈跟踪：

    Exception in thread "main" org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'stormpathAccountService' defined in file [/Users/jfitzgerald/Projects/parsezilla-api-partner/build/classes/main/com/schoolzilla/api/application/credentials/StormpathAccountService.class]: Instantiation of bean failed; nested exception is org.springframework.beans.BeanInstantiationException: Could not instantiate bean class [com.schoolzilla.api.application.credentials.StormpathAccountService]: Constructor threw exception; nested exception is java.lang.NullPointerException
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateBean(AbstractAutowireCapableBeanFactory.java:1077)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1022)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:504)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:475)
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:302)
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:228)
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:298)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:193)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:706)
    at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:762)
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:482)
    at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.refresh(EmbeddedWebApplicationContext.java:109)
    at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:691)
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:320)
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:952)
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:941)
    at org.springframework.boot.SpringApplication$run.call(Unknown Source)
    at org.codehaus.groovy.runtime.callsite.CallSiteArray.defaultCall(CallSiteArray.java:45)
    at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:108)
    at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:120)
    at com.schoolzilla.api.Application.main(Application.groovy:18)
Caused by: org.springframework.beans.BeanInstantiationException: Could not instantiate bean class [com.schoolzilla.api.application.credentials.StormpathAccountService]: Constructor threw exception; nested exception is java.lang.NullPointerException
    at org.springframework.beans.BeanUtils.instantiateClass(BeanUtils.java:164)
    at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:89)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateBean(AbstractAutowireCapableBeanFactory.java:1070)
    ... 20 more
Caused by: java.lang.NullPointerException
    at org.codehaus.groovy.runtime.callsite.AbstractCallSite.createGroovyObjectGetPropertySite(AbstractCallSite.java:254)
    at org.codehaus.groovy.runtime.callsite.AbstractCallSite.acceptGroovyObjectGetProperty(AbstractCallSite.java:239)
    at org.codehaus.groovy.runtime.callsite.AbstractCallSite.callGroovyObjectGetProperty(AbstractCallSite.java:231)
    at com.schoolzilla.api.application.credentials.StormpathAccountService.<init>(StormpathAccountService.groovy:37)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
    at java.lang.reflect.Constructor.newInstance(Constructor.java:408)
    at org.springframework.beans.BeanUtils.instantiateClass(BeanUtils.java:148)
    ... 22 more

这是给我带来问题的代码：

@Service
class StormpathAccountService implements AccountService {

//This is where my problem lies
    @Autowired
    StormpathProperties stormpathProperties

    private def logger = LogFactory.getLog(StormpathAccountService)

    private def path = System.getProperty("user.home") + stormpathProperties.apiKeyLocation

//more stuff here...

    }
}

正在实现的 Groovy 接口：

interface AccountService {
    def createAccount(PartnerAccount account);
    def deleteAccount(PartnerAccount account);
    ApiKey fetchApiKey(PartnerAccount account);
}

属性类：

@Configuration
@ConfigurationProperties(prefix = "stormpath")
class StormpathProperties {
    String apiKeyLocation
    String accountUrl
}

以及我的 application.properties 文件中的属性名称：

stormpath.apiKeyLocation
stormpath.accountUrl

最后是我的主要应用程序类：

@Configuration
@ComponentScan
@EnableAutoConfiguration
@EnableTransactionManagement
@EnableConfigurationProperties
class Application {

    static void main(String[] args) {
        SpringApplication.run Application, args
    }

}

出于类加载器的原因，我查看了其他一些建议，例如实现基于 Java 的接口而不是基于 Groovy 的接口，但到目前为止，这对我没有用。我还尝试将注入方法更改为基于构造函数。类已成功注入，但实际属性为空。

我已经花了几天的时间在这里敲击键盘，所以任何进一步的帮助和/或解释为什么它不起作用将不胜感激。

编辑： 这是使用 AccountService.groovy 的其他服务：

@Service
@Scope(proxyMode = ScopedProxyMode.TARGET_CLASS)
class PartnerApplicationService {

    def logger = LoggerFactory.getLogger(PartnerApplicationService)

    @Autowired
    PartnerApplicationRepository repository

    @Autowired
    CredentialsRepository credentialsRepository

    @Autowired
    PartnerService partnerService

    @Autowired
    AccountService accountService

//lots more stuff...
}

Answer 1

嗯，我想我找到了适合我的解决方案。我手动将 StormpathProperties 文件作为@ComponentScan 的一部分包含在内。我不知道为什么这需要明确说明其他一切都可以正确使用@ComponentScan。

Answer 2

我认为您没有将 StormpathAccountService bean 注入到控制器或其他使用它的类中，如果不尝试注入它：

@Autowired
StormpathAccountService stormpathAccountService;

或者： 在其中注入AccountService 接口：

@Autowired
AccountService accountService;