jersey - 无法在我的资源类中注入(inject) @Service 和 @Contract 依赖项

Question

根据本博客的指南，Roll your own Auto Discovery with Jersey and HK2 ，我有以下资源 POJO:

@Path("Test")
public class TestResource {
    @Inject
    private TestService service;
    @GET
    @Produces({MediaType.APPLICATION_JSON, MediaType.APPLICATION_XML})
    public Set<Test> getTests() {
        return service.getAllTests();
    }
}

TestService:

@Contract
public interface TestService {
    public Set<Test> getAllTests();
}

TestServiceImpl

@Service
public class TestServiceImpl implements TestService {

    @Override
    public Set<Test> getAllTests() {
        Set<Test> tests = new HashSet<>();
        Test c = new Test();
        c.setName("test");
        tests.add(c);
        return tests;
    }
}

pom.xml 中的 Jersey 依赖项版本为 2.25.1

   <dependencyManagement>
    <dependencies>
        <dependency>
            <groupId>org.glassfish.jersey</groupId>
            <artifactId>jersey-bom</artifactId>
            <version>${jersey.version}</version>
            <type>pom</type>
            <scope>import</scope>
        </dependency>
    </dependencies>
</dependencyManagement>

<dependencies>
<dependency>
<groupId>javax.ws.rs</groupId>
<artifactId>javax.ws.rs-api</artifactId>
<version>2.0</version>
</dependency>
    <dependency>
        <groupId>org.glassfish.jersey.containers</groupId>
        <artifactId>jersey-container-servlet-core</artifactId>
        <!-- use the following artifactId if you don't need servlet 2.x compatibility -->
        <!-- artifactId>jersey-container-servlet</artifactId -->
    </dependency>
     <dependency>
        <groupId>org.glassfish.jersey.bundles</groupId>
        <artifactId>jaxrs-ri</artifactId>
        </dependency>
     <dependency>
         <groupId>org.glassfish.jersey.media</groupId>
         <artifactId>jersey-media-json-jackson</artifactId>
     </dependency>
     <dependency>
         <groupId>org.glassfish.hk2</groupId>
         <artifactId>hk2</artifactId>
         <version>2.5.0-b36</version>
     </dependency>

为了让 Jersey 自动扫描 @Service 和 @Contract 类，我使用了版本 2.5.0-b36 的 inhabitant-generator 插件:

<plugin>
  <groupId>org.glassfish.hk2</groupId>
  <artifactId>hk2-inhabitant-generator</artifactId>
  <version>2.5.0-b36</version>
  <executions>
    <execution>
      <goals>
        <goal>generate-inhabitants</goal>
      </goals>
    </execution>
  </executions>
</plugin>

有相应的Feature实现:

public class AutoServiceDiscovery implements Feature {

@Override
public boolean configure(FeatureContext context) {
    ServiceLocator locator = ServiceLocatorProvider.getServiceLocator(context);
    DynamicConfigurationService dcs = locator.getService(DynamicConfigurationService.class);
    Populator populator = dcs.getPopulator();
    try {
        populator.populate(new ClasspathDescriptorFileFinder(this.getClass().getClassLoader()),
                new DuplicatePostProcessor());
    } catch (IOException | MultiException ex) {
        Logger.getLogger(this.getClass().getName()).log(Level.SEVERE, null, ex);
    }
    return true;
}

}

它确实是通过我的 ResourceConfig 类注册的:

@ApplicationPath("/*")
public class ApplicationConfig extends ResourceConfig {
    public ApplicationConfig() {
        packages("resources");
        register(new AutoServiceDiscovery());
}

}但是，我向 /test 发送请求，收到以下错误:

MultiException has 3 exceptions.  They are:
1. org.glassfish.hk2.api.UnsatisfiedDependencyException: There was no object available for 
injection at SystemInjecteeImpl(requiredType=TestService,parent=TestResource,qualifiers=
{},position=-1,optional=false,self=false,unqualified=null,1947073589)
2. java.lang.IllegalArgumentException: While attempting to resolve the dependencies of 
rx.practice.ee.jaxrs.resources.TestResource errors were found
3. java.lang.IllegalStateException: Unable to perform operation: resolve on 
rx.practice.ee.jaxrs.resources.TestResource

org.jvnet.hk2.internal.Collector.throwIfErrors(Collector.java:89)
org.jvnet.hk2.internal.ClazzCreator.resolveAllDependencies(ClazzCreator.java:250)
org.jvnet.hk2.internal.ClazzCreator.create(ClazzCreator.java:358)
org.jvnet.hk2.internal.SystemDescriptor.create(SystemDescriptor.java:487)
org.glassfish.jersey.process.internal.RequestScope.findOrCreate(RequestScope.java:162)
...

问题:有人知道为什么@Service类无法注入(inject)吗？我正在使用 Tomcat 服务器

Answer 1

经过几天的研究inhabitat-generator的源代码，我发现在 Web 应用程序包的情况下，war ，定位器文件未在 META-INF/hk2-locator 中生成如 HK2 Inhabitant Generator office site 所示如果使用 jar作为部署包。 source code of AbstractInhabitantsGeneratorMojo.java告诉如果 war ，定位器文件在 hk2-locator 中生成，而HK2 Inhabitant Generator office site中没有提到这一点。 .

但是，在构造 ClasspathDescriptorFileFinder 时如果引导类中没有目录名称参数，AutoServiceDiscovery ，仅与 jar 兼容作为部署包，这意味着它只能在 META-INF/hk2-locator 中查找文件.

所以更好的解决方案是不要使用 inhabitant-generator插件但是 metadata-generator依赖项，它是编译时的一个注释处理器，并且被证明是开箱即用的。

如果有人坚持使用这个插件，他/她可以创建他/她自己的ClasspathDescriptorFileFinder这样它就能够从hk2-locator找到定位器文件

最后但并非最不重要的一点是，我还尝试使用 inhabitants-generator插件的选项用于在hk2-locator中生成定位器文件，但这似乎也是几乎不可能的