Guice Jersey ClientConfig MessageBodyWriters和Injection

Question

从客户端的角度来看，我正在尝试让Guice injection与Jersey MessageBodyReader/MessageBodyWriter协同工作。我已经用Guice正确启动了服务器。我的问题是客户的问题。

我拼凑了以下演示错误的代码：SEVERE: Missing dependency for constructor public FooExample$FooReader(FooExample$FooUnmarshaller) at parameter index 0

import java.io.IOException;
import java.io.InputStream;
import java.lang.annotation.Annotation;
import java.lang.reflect.Type;

import javax.inject.Inject;
import javax.ws.rs.WebApplicationException;
import javax.ws.rs.core.MediaType;
import javax.ws.rs.core.MultivaluedMap;
import javax.ws.rs.core.UriBuilder;
import javax.ws.rs.ext.MessageBodyReader;

import com.google.inject.AbstractModule;
import com.google.inject.Guice;
import com.google.inject.Injector;
import com.google.inject.Provides;
import com.sun.jersey.api.client.Client;
import com.sun.jersey.api.client.WebResource;
import com.sun.jersey.api.client.config.ClientConfig;
import com.sun.jersey.api.client.config.DefaultClientConfig;

class FooExample {
  public static void main(String[] args) {
    Injector i = Guice.createInjector(new FooExample().new FooModule());
    WebResource service = i.getInstance(WebResource.class);

    service.path("bar")
        .accept(MediaType.APPLICATION_XML)
        .put(String.class, "test123");
  }

  public class FooModule extends AbstractModule{
    @Override
    protected void configure() {
      bind(FooUnmarshaller.class).to(SimpleFooUnmarshaller.class);
    }

    @Provides
    public WebResource configuredClient() {
      ClientConfig config = new DefaultClientConfig();
      config.getClasses().add(FooReader.class);
      return Client.create(config).resource(
          UriBuilder.fromUri("http://localhost:8080/foo").build());
    }
  }

  public static class Foo {}

  public static interface FooUnmarshaller {
    public Foo unmarshall(InputStream is);
  }

  public static class SimpleFooUnmarshaller implements FooUnmarshaller {
    @Override
    public Foo unmarshall(InputStream is) {
      return new Foo();
    }
  }

  public static class FooReader implements MessageBodyReader<Foo> {
    private final FooUnmarshaller marshaller;

    @Inject
    public FooReader(FooUnmarshaller marshaller) {
      this.marshaller = marshaller;
    }

    @Override
    public boolean isReadable(
        Class<?> type,
        Type genericType,
        Annotation[] annotations,
        MediaType mediaType) {
      return true;
    }

    @Override
    public Foo readFrom(
        Class<Foo> type,
        Type genericType,
        Annotation[] annotations,
        MediaType mediaType,
        MultivaluedMap<String, String> httpHeaders,
        InputStream entityStream) throws IOException, WebApplicationException {
      return marshaller.unmarshall(entityStream);
    }
  }
}

我在哪里得到控制台输出：

Oct 23, 2012 3:17:22 PM com.sun.jersey.spi.inject.Errors processErrorMessages
SEVERE: The following errors and warnings have been detected with resource and/or provider classes:
  SEVERE: Missing dependency for constructor public FooExample$FooReader(FooExample$FooUnmarshaller) at parameter index 0
Exception in thread "main" com.google.inject.ProvisionException: Guice provision errors:

1) Error in custom provider, com.sun.jersey.spi.inject.Errors$ErrorMessagesException
  at FooExample$FooModule.configuredClient(FooExample.java:40)
  while locating com.sun.jersey.api.client.WebResource

1 error
  at com.google.inject.internal.InjectorImpl$4.get(InjectorImpl.java:987)
  at com.google.inject.internal.InjectorImpl.getInstance(InjectorImpl.java:1013)
  at FooExample.main(FooExample.java:25)
Caused by: com.sun.jersey.spi.inject.Errors$ErrorMessagesException
  at com.sun.jersey.spi.inject.Errors.processErrorMessages(Errors.java:170)
  at com.sun.jersey.spi.inject.Errors.postProcess(Errors.java:136)
  at com.sun.jersey.spi.inject.Errors.processWithErrors(Errors.java:199)
  at com.sun.jersey.api.client.Client.<init>(Client.java:187)
  at com.sun.jersey.api.client.Client.<init>(Client.java:170)
  at com.sun.jersey.api.client.Client.create(Client.java:679)
  at FooExample$FooModule.configuredClient(FooExample.java:42)
  at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
  at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
  at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
  at java.lang.reflect.Method.invoke(Method.java:616)
  at com.google.inject.internal.ProviderMethod.get(ProviderMethod.java:104)
  at com.google.inject.internal.InternalFactoryToProviderAdapter.get(InternalFactoryToProviderAdapter.java:40)
  at com.google.inject.internal.InjectorImpl$4$1.call(InjectorImpl.java:978)
  at com.google.inject.internal.InjectorImpl.callInContext(InjectorImpl.java:1024)
  at com.google.inject.internal.InjectorImpl$4.get(InjectorImpl.java:974)
  ... 2 more

我感觉我需要使用GuiceComponentProviderFactory，但我似乎找不到任何关于它的文档，也找不到使用ClientConfig的IoCComponentProviderFactory。任何帮助都将不胜感激。谢谢!

Answer 1

所以我通过猜测和检查解决了我自己的问题。我不能确定这是不是想要做的事情，但这是有效的。

Client类有一个方法：public static Client create(ClientConfig cc, IoCComponentProviderFactory provider)，我向它传递了一个GuiceComponentProviderFactory，事情就解决了。上面代码的工作版本是：

import java.io.IOException;
import java.io.InputStream;
import java.lang.annotation.Annotation;
import java.lang.reflect.Type;

import javax.inject.Inject;
import javax.ws.rs.WebApplicationException;
import javax.ws.rs.core.MediaType;
import javax.ws.rs.core.MultivaluedMap;
import javax.ws.rs.core.UriBuilder;
import javax.ws.rs.ext.MessageBodyReader;

import com.google.inject.AbstractModule;
import com.google.inject.Guice;
import com.sun.jersey.api.client.Client;
import com.sun.jersey.api.client.WebResource;
import com.sun.jersey.api.client.config.DefaultClientConfig;
import com.sun.jersey.api.core.DefaultResourceConfig;
import com.sun.jersey.core.spi.component.ioc.IoCComponentProviderFactory;
import com.sun.jersey.guice.spi.container.GuiceComponentProviderFactory;

class FooExample {
  public static void main(String[] args) {
    WebResource service = configuredClient();

    service.path("bar")
        .accept(MediaType.APPLICATION_XML)
        .put(String.class, "test123");
  }

  private static WebResource configuredClient() {
    DefaultClientConfig config = new DefaultClientConfig();
    config.getClasses().add(FooReader.class);
    return Client.create(config, provider()).resource(
        UriBuilder.fromUri("http://localhost:8080/foo").build());
  }

  private static IoCComponentProviderFactory provider() {
    return new GuiceComponentProviderFactory(
        new DefaultResourceConfig(),
        Guice.createInjector(new FooExample().new FooModule()));
  }

  public class FooModule extends AbstractModule {
    @Override
    protected void configure() {
      bind(FooUnmarshaller.class).to(SimpleFooUnmarshaller.class);
    }
  }

  public static class Foo {}

  public static interface FooUnmarshaller {
    public Foo unmarshall(InputStream is);
  }

  public static class SimpleFooUnmarshaller implements FooUnmarshaller {
    @Override
    public Foo unmarshall(InputStream is) {
      return new Foo();
    }
  }

  public static class FooReader implements MessageBodyReader<Foo> {
    private final FooUnmarshaller marshaller;

    @Inject
    public FooReader(FooUnmarshaller marshaller) {
      this.marshaller = marshaller;
    }

    @Override
    public boolean isReadable(
        Class<?> type,
        Type genericType,
        Annotation[] annotations,
        MediaType mediaType) {
      return true;
    }

    @Override
    public Foo readFrom(
        Class<Foo> type,
        Type genericType,
        Annotation[] annotations,
        MediaType mediaType,
        MultivaluedMap<String, String> httpHeaders,
        InputStream entityStream) throws IOException, WebApplicationException {
      return marshaller.unmarshall(entityStream);
    }
  }
}

和输出

Oct 23, 2012 5:17:11 PM com.sun.jersey.guice.spi.container.GuiceComponentProviderFactory getComponentProvider
INFO: Binding FooExample$FooReader to GuiceInstantiatedComponentProvider
Exception in thread "main" com.sun.jersey.api.client.UniformInterfaceException: PUT http://localhost:8080/foo/bar returned a response status of 404 Not Found
  at com.sun.jersey.api.client.WebResource.handle(WebResource.java:686)
  at com.sun.jersey.api.client.WebResource.access$200(WebResource.java:74)
  at com.sun.jersey.api.client.WebResource$Builder.put(WebResource.java:537)
  at FooExample.main(FooExample.java:28)

这意味着guice绑定起作用了！=)