使用spring.factories加載自定義自動配置時出現FileNotFoundException

Question

更新：如果我簡單地將extension項目作爲master的依賴項添加，我有同樣的錯誤。

更新2：我創建了一個GitHub庫重現錯誤：https://github.com/papagno/spring-factories-test

---

我和春天引導和spring.factories文件試驗。所以，我創建了兩個簡單的項目：

• 站長：
  • 這是一個春天啓動應用程序（1.4.3）與起動網絡和起動器的依賴關係。
  • 我還添加了<layout>ZIP</layout>作爲spring-boot-maven-plugin的配置。

• 擴展

  • 這是一個簡單的Spring啓動應用程序（1.4.3）只有spring-boot-starter作爲一個依賴。
  • 它包含resources/META-INF以下spring.factories文件： org.springframework.boot.autoconfigure.EnableAutoConfiguration=\ my.package.extension.ExtensionAutoConfiguration

  • 它還包含被註釋只有@Configuration的my.package.ExtensionAutoConfiguration類，並聲明瞭一個@Bean：

    package my.package.extension; 
    
    import org.springframework.context.annotation.Bean; 
    import org.springframework.context.annotation.Configuration; 
    
    @Configuration 
    public class ExtensionAutoConfiguration 
    { 
        @Bean 
        ExtensionService extensionService() 
        { 
         return new ExtensionService(); 
        } 
    } 
    

我使用maven編譯這兩個項目，將兩個jar放在同一個文件夾中，然後使用以下命令運行master： java -Dloader.path=. -jar master-0.0.1-SNAPSHOT.jar

的spring.factories認識，但是當春嘗試實例我的自動配置類，我得到了FileNotFoundException該類。

這是堆棧跟蹤：

org.springframework.beans.factory.BeanDefinitionStoreException: Failed to process import candidates for configuration class [my.package.master.MasterApplication]; nested exception is java.lang.IllegalStateException: java.io.FileNotFoundException: class path resource [my/package/extension/ExtensionAutoConfiguration.class] cannot be opened because it does not exist 
    at org.springframework.context.annotation.ConfigurationClassParser.processDeferredImportSelectors(ConfigurationClassParser.java:482) ~[spring-context-4.3.5.RELEASE.jar!/:4.3.5.RELEASE] 
    at org.springframework.context.annotation.ConfigurationClassParser.parse(ConfigurationClassParser.java:184) ~[spring-context-4.3.5.RELEASE.jar!/:4.3.5.RELEASE] 
    at org.springframework.context.annotation.ConfigurationClassPostProcessor.processConfigBeanDefinitions(ConfigurationClassPostProcessor.java:308) ~[spring-context-4.3.5.RELEASE.jar!/:4.3.5.RELEASE] 
    at org.springframework.context.annotation.ConfigurationClassPostProcessor.postProcessBeanDefinitionRegistry(ConfigurationClassPostProcessor.java:228) ~[spring-context-4.3.5.RELEASE.jar!/:4.3.5.RELEASE] 
    at org.springframework.context.support.PostProcessorRegistrationDelegate.invokeBeanDefinitionRegistryPostProcessors(PostProcessorRegistrationDelegate.java:270) ~[spring-context-4.3.5.RELEASE.jar!/:4.3.5.RELEASE] 
    at org.springframework.context.support.PostProcessorRegistrationDelegate.invokeBeanFactoryPostProcessors(PostProcessorRegistrationDelegate.java:93) ~[spring-context-4.3.5.RELEASE.jar!/:4.3.5.RELEASE] 
    at org.springframework.context.support.AbstractApplicationContext.invokeBeanFactoryPostProcessors(AbstractApplicationContext.java:686) ~[spring-context-4.3.5.RELEASE.jar!/:4.3.5.RELEASE] 
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:524) ~[spring-context-4.3.5.RELEASE.jar!/:4.3.5.RELEASE] 
    at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.refresh(EmbeddedWebApplicationContext.java:122) ~[spring-boot-1.4.3.RELEASE.jar!/:1.4.3.RELEASE] 
    at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:761) [spring-boot-1.4.3.RELEASE.jar!/:1.4.3.RELEASE] 
    at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:371) [spring-boot-1.4.3.RELEASE.jar!/:1.4.3.RELEASE] 
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:315) [spring-boot-1.4.3.RELEASE.jar!/:1.4.3.RELEASE] 
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1186) [spring-boot-1.4.3.RELEASE.jar!/:1.4.3.RELEASE] 
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1175) [spring-boot-1.4.3.RELEASE.jar!/:1.4.3.RELEASE] 
    at my.package.master.MasterApplication.main(MasterApplication.java:10) [classes!/:0.0.1-SNAPSHOT] 
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_101] 
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_101] 
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_101] 
    at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_101] 
    at org.springframework.boot.loader.MainMethodRunner.run(MainMethodRunner.java:48) [master-0.0.1-SNAPSHOT.jar:0.0.1-SNAPSHOT] 
    at org.springframework.boot.loader.Launcher.launch(Launcher.java:87) [master-0.0.1-SNAPSHOT.jar:0.0.1-SNAPSHOT] 
    at org.springframework.boot.loader.Launcher.launch(Launcher.java:50) [master-0.0.1-SNAPSHOT.jar:0.0.1-SNAPSHOT] 
    at org.springframework.boot.loader.PropertiesLauncher.main(PropertiesLauncher.java:521) [master-0.0.1-SNAPSHOT.jar:0.0.1-SNAPSHOT] 
Caused by: java.lang.IllegalStateException: java.io.FileNotFoundException: class path resource [my/package/extension/ExtensionAutoConfiguration.class] cannot be opened because it does not exist 
    at org.springframework.boot.autoconfigure.EnableAutoConfigurationImportSelector.selectImports(EnableAutoConfigurationImportSelector.java:94) ~[spring-boot-autoconfigure-1.4.3.RELEASE.jar!/:1.4.3.RELEASE] 
    at org.springframework.context.annotation.ConfigurationClassParser.processDeferredImportSelectors(ConfigurationClassParser.java:474) ~[spring-context-4.3.5.RELEASE.jar!/:4.3.5.RELEASE] 
    ... 22 common frames omitted 
Caused by: java.io.FileNotFoundException: class path resource [my/package/extension/ExtensionAutoConfiguration.class] cannot be opened because it does not exist 
    at org.springframework.core.io.ClassPathResource.getInputStream(ClassPathResource.java:172) ~[spring-core-4.3.5.RELEASE.jar!/:4.3.5.RELEASE] 
    at org.springframework.core.type.classreading.SimpleMetadataReader.<init>(SimpleMetadataReader.java:50) ~[spring-core-4.3.5.RELEASE.jar!/:4.3.5.RELEASE] 
    at org.springframework.core.type.classreading.SimpleMetadataReaderFactory.getMetadataReader(SimpleMetadataReaderFactory.java:98) ~[spring-core-4.3.5.RELEASE.jar!/:4.3.5.RELEASE] 
    at org.springframework.boot.type.classreading.ConcurrentReferenceCachingMetadataReaderFactory.createMetadataReader(ConcurrentReferenceCachingMetadataReaderFactory.java:89) ~[spring-boot-1.4.3.RELEASE.jar!/:1.4.3.RELEASE] 
    at org.springframework.boot.type.classreading.ConcurrentReferenceCachingMetadataReaderFactory.getMetadataReader(ConcurrentReferenceCachingMetadataReaderFactory.java:76) ~[spring-boot-1.4.3.RELEASE.jar!/:1.4.3.RELEASE] 
    at org.springframework.core.type.classreading.SimpleMetadataReaderFactory.getMetadataReader(SimpleMetadataReaderFactory.java:93) ~[spring-core-4.3.5.RELEASE.jar!/:4.3.5.RELEASE] 
    at org.springframework.boot.autoconfigure.AutoConfigurationSorter$AutoConfigurationClasses.<init>(AutoConfigurationSorter.java:110) ~[spring-boot-autoconfigure-1.4.3.RELEASE.jar!/:1.4.3.RELEASE] 
    at org.springframework.boot.autoconfigure.AutoConfigurationSorter.getInPriorityOrder(AutoConfigurationSorter.java:54) ~[spring-boot-autoconfigure-1.4.3.RELEASE.jar!/:1.4.3.RELEASE] 
    at org.springframework.boot.autoconfigure.EnableAutoConfigurationImportSelector.sort(EnableAutoConfigurationImportSelector.java:193) ~[spring-boot-autoconfigure-1.4.3.RELEASE.jar!/:1.4.3.RELEASE] 
    at org.springframework.boot.autoconfigure.EnableAutoConfigurationImportSelector.selectImports(EnableAutoConfigurationImportSelector.java:89) ~[spring-boot-autoconfigure-1.4.3.RELEASE.jar!/:1.4.3.RELEASE] 
    ... 23 common frames omitted 

難道我做錯了什麼？我能做些什麼來了解正在發生的事情？謝謝。

Answer 1

你的分機號必須是一個春天引導應用程序（無父spring-boot-starter-parent）。

當你聲明彈簧引導啓動父父，產生的罐子被重新包裝用SRING-Boot的味道和類不是在預期的文件夾中。如果您打開extension-0.0.1-SNAPSHOT.jar，則這些類位於BOOT-INF/classes中，因此當該jar用作庫時，不會找到類。這些類需要位於jar內部的根目錄下。

使用以下pom.xml爲擴展項目：

<?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 http://maven.apache.org/xsd/maven-4.0.0.xsd"> 
    <modelVersion>4.0.0</modelVersion> 

    <groupId>com.example</groupId> 
    <artifactId>extension</artifactId> 
    <version>0.0.1-SNAPSHOT</version> 
    <packaging>jar</packaging> 

    <name>extension</name> 
    <description>Demo project for Spring Boot</description> 

    <properties> 
     <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> 
     <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding> 
     <java.version>1.8</java.version> 
    </properties> 

    <dependencyManagement> 
     <dependencies> 
      <dependency> 
       <groupId>org.springframework.boot</groupId> 
       <artifactId>spring-boot-starter-parent</artifactId> 
       <version>1.4.3.RELEASE</version> 
       <type>pom</type> 
       <scope>import</scope> 
      </dependency> 
     </dependencies> 
    </dependencyManagement> 

    <dependencies> 
     <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> 

     <dependency> 
      <groupId>com.example</groupId> 
      <artifactId>api</artifactId> 
      <version>1.0-SNAPSHOT</version> 
     </dependency> 
    </dependencies> 
</project> 

在上面的代碼示例中，我還是宣佈彈簧引導啓動父爲dependencyManagement - import，所以版本聲明繼承。但是，spring-boot-maven-plugin不會被執行，jar將不會被重新打包，並且可以用作庫。