Question

在Jersey Rest应用程序中使用DI时出错：

org.glassfish.hk2.api.UnsatisfiedDependencyException: There was no object available for injection at SystemInjecteeImpl(requiredType=PricingService,parent=PricingResource,qualifiers={},position=0,optional=false,self=false,unqualified=null,1633188703)

我对这个概念很陌生，看起来很复杂，因为有些例子似乎已被弃用了。据我所知，有几种方法可以使DI工作：原生HK2，Spring / HK2 Bridge。什么是更简单，更直接的配置？如何为Jersey 2.x以编程方式（而不是XML的粉丝）进行设置？

ResourceConfig

import org.glassfish.jersey.server.ResourceConfig;

public class ApplicationConfig  extends ResourceConfig {
    public ApplicationConfig() {
        register(new ApplicationBinder());
        packages(true, "api");
    }
}

AbstractBinder

public class ApplicationBinder extends AbstractBinder {
    @Override
    protected void configure() {
        bind(PricingService.class).to(PricingService.class).in(Singleton.class);
    }
}

PricingResource

@Path("/prices")
public class PricingResource {
    private final PricingService pricingService;

    @Inject
    public PricingResource(PricingService pricingService) {
        this.pricingService = pricingService;
    }

    @GET
    @Produces(MediaType.APPLICATION_JSON)
    public Collection<Price> findPrices() {
        return pricingService.findPrices();
    }
}

PricingService

@Singleton
public class PricingService {
   // no constructors...
// findPrices() ...

}

更新

public class Main {
    public static final String BASE_URI = "http://localhost:8080/api/";

    public static HttpServer startServer() {
        return createHttpServerWith(new ResourceConfig().packages("api").register(JacksonFeature.class));
    }

    private static HttpServer createHttpServerWith(ResourceConfig rc) {
        HttpServer httpServer = GrizzlyHttpServerFactory.createHttpServer(URI.create(BASE_URI), rc);
        StaticHttpHandler staticHttpHandler = new StaticHttpHandler("src/main/webapp");
        staticHttpHandler.setFileCacheEnabled(false);
        staticHttpHandler.start();
        httpServer.getServerConfiguration().addHttpHandler(staticHttpHandler);
        return httpServer;
    }

    public static void main(String[] args) throws IOException {
        System.setProperty("java.util.logging.config.file", "src/main/resources/logging.properties");
        final HttpServer server = startServer();

        System.out.println(String.format("Jersey app started with WADL available at "
                + "%sapplication.wadl\nHit enter to stop it...", BASE_URI));
        server.start();
        System.in.read();
        server.stop();
    }

}

UPDATE3：

public class PricingResourceTest extends JerseyTest {
    @Mock
    private PricingService pricingServiceMock;

    @Override
    protected Application configure() {
        MockitoAnnotations.initMocks(this);
        enable(TestProperties.LOG_TRAFFIC);
        enable(TestProperties.DUMP_ENTITY);

        ResourceConfig config = new ResourceConfig(PricingResource.class);
        config.register(new AbstractBinder() {
            @Override
            protected void configure() {
                bind(pricingServiceMock).to(PricingService.class);
            }
        });
        return config;
    }

    @Test
    public void testFindPrices(){
        when(pricingServiceMock.findPrices()).thenReturn(getMockedPrices());
        Response response  = target("/prices")
                .request()
                .get();
        verify(pricingServiceMock).findPrices();
        List<Price> prices = response.readEntity(new GenericType<List<Price>>(){});
//        assertEquals("Should return status 200", 200, response.getStatus());
        assertTrue(prices.get(0).getId() == getMockedPrices().get(0).getId());
    }

    private List<Price> getMockedPrices(){
        List<Price> mockedPrices = Arrays.asList(new Price(1L, 12.0, 50.12, 12L));
        return mockedPrices;
    }
}

JUnit输出：

INFO: 1 * Client response received on thread main
1 < 200
1 < Content-Length: 4
1 < Content-Type: application/json
[{}]


java.lang.AssertionError

调试时：

prices.get(0)是Price对象，已将null分配给所有字段。

UPDATE4：

已添加到configure()：

 config.register(JacksonFeature.class);
 config.register(JacksonJsonProvider.class);

现在Junit输出更好一点：

INFO: 1 * Client response received on thread main
1 < 200
1 < Content-Length: 149
1 < Content-Type: application/json
[{"id":2,"recurringPrice":122.0,"oneTimePrice":6550.12,"recurringCount":2},{"id":2,"recurringPrice":122.0,"oneTimePrice":6550.12,"recurringCount":2}]

确实列表prices的正确数量为prices，但所有价格的字段都为 null 。这导致假设问题可能是阅读实体：

List<Price> prices = response.readEntity(new GenericType<List<Price>>(){});

以下是修复方法

将Moxy依赖项更改为：

<dependency>
    <groupId>org.glassfish.jersey.media</groupId>
    <artifactId>jersey-media-json-jackson</artifactId>
</dependency>

并在'Price'对象上添加注释。

@XmlRootElement
@JsonIgnoreProperties(ignoreUnknown = true)

Answer 1

忘记InjectableProvider。你不需要它。问题是 mock 服务不是正在注入的服务。它是由DI框架创建的。因此，您正在检查模拟服务的更改，这些更改从未被触及过。

所以你需要做的是将模拟与DI框架绑定。您只需创建另一个AbstractBinder进行测试即可。它可以是一个简单的匿名，你将绑定模拟

ResourceConfig config = new ResourceConfig(PricingResource.class);
config.register(new AbstractBinder() {
    @Override
    protected void configure() {
        bind(pricingServiceMock).to(PricingService.class);
    }
});

在这里，您只需绑定模拟服务即可。所以框架会将模拟注入资源。现在，当您在请求中修改它时，将在断言中看到更改

哦，您仍需要执行when(..).then(..)初始化模拟服务中的数据。这也是你所缺少的

@Test
public void testFindPrices(){
    Mockito.when(pricingServiceMock.findSomething()).thenReturn(list);

Answer 2

我通过向我的应用程序添加以下依赖项来解决此问题。编译组：'org.glassfish.jersey.containers.glassfish'，名称：'jersey-gf-cdi'，版本：'2.14'

然后就不需要任何“AbstractBinder”相关代码了。

Answer 3

如果beans.xml丢失或放置在错误的位置，则会发生相同的错误。这对我有帮助：Where should beans.xml be placed?

UnsatisfiedDependencyException：SystemInjecteeImpl中没有可用于注入的对象

以下是修复方法

3 个答案: