使用 FactoryModuleBuilder 的 HK2 等效辅助注入

Question

感谢迁移到球衣 2，我需要从 guice 迁移到 HK2。对于我的一些依赖项，我有一个辅助注入方法，我无法在 HK2 中实现这些依赖项。看起来它应该通过Custom Injection Resolvers 解决，但我真的不知道如何解决。这些例子对我来说不够清楚..

这是它在 Guice 上的外观：

public interface MyFactory {
    public MyClass createMyClass(@Assisted String dynamicParameter);
    public HisClass createHisClass(@Assisted String dynamicParameter);
    ...
}

binder.install(new FactoryModuleBuilder().build(MyFactory.class));

public class MyClass {
   ...
   @Inject
   public MyClass(@Assisted String dynamicParameter, SomeService someOtherServiceInjectedAutomatically){
      ...
   }
}

如何在 HK2 上实现这个？

Answer 1

发布问题后，我想这样做：

public class MyFactoryImpl implements MyFactory{

   private final SomeService someService;

   @Inject
   public MyFactoryImpl(SomeService someService){
      this.someService = someService;
   }

   public MyClass createMyClass(String dynamicParameter){
      return new MyClass(dynamicParameter, someService);
   }

   ...
}

Answer 2

有一个Guice-Bridge :-D

<dependency>
    <groupId>org.glassfish.hk2</groupId>
    <artifactId>guice-bridge</artifactId>
    <version>${hk2.version}</version>
</dependency>

这是一个使用 Guice 3.0 和 HK2 2.3.0（与 Jersey 2.13 捆绑在一起）的示例。这只是一个独立的，但它应该在 Jersey 环境中同样工作。

Guice 类

public class GuiceGreeter {
    public String getGreeting(String name) {
        return "Hello, " + name;
    }
}

import com.google.inject.assistedinject.Assisted;
import javax.inject.Inject;

public class Message {
    private final String message;  
    @Inject
    public Message(GuiceGreeter greeter, @Assisted String name) {
        message = greeter.getGreeting(name);
    }
    public String getMessage() {
        return message;
    }
}

public interface GuiceMessageFactory {
    public Message getMessage(String name);
}

import com.google.inject.AbstractModule;
import com.google.inject.assistedinject.FactoryModuleBuilder;

public class GuiceMessageModule extends AbstractModule {
    @Override
    protected void configure() {
        install(new FactoryModuleBuilder().build(GuiceMessageFactory.class));
        bind(GuiceGreeter.class);
    }   
}

HK2服务，注入Guice工厂

import javax.inject.Inject;

public class HK2Service {
    private final GuiceMessageFactory messageFactory;

    @Inject
    public HK2Service(GuiceMessageFactory messageFactory) {
        this.messageFactory = messageFactory;
    }

    public void printMessage(String name) {
        System.out.println(messageFactory.getMessage(name).getMessage());
    }
}

主要

import com.google.inject.Guice;
import com.google.inject.Injector;
import org.glassfish.hk2.api.ServiceLocator;
import org.glassfish.hk2.api.ServiceLocatorFactory;
import org.glassfish.hk2.utilities.ServiceLocatorUtilities;
import org.jvnet.hk2.guice.bridge.api.GuiceBridge;
import org.jvnet.hk2.guice.bridge.api.GuiceIntoHK2Bridge;

public class Main {
    public static void main(String[] args) {
        // Create service locator. In Jersey context, you should be able to
        // inject the `ServiceLocator` into the `Application/ResourceConfig` 
        // subclass constructor, or as a field
        ServiceLocatorFactory factory = ServiceLocatorFactory.getInstance();
        ServiceLocator locator = factory.create("SimpleServiceLocator");

        // bridge the two frameworks to allow Guice injected services
        GuiceBridge.getGuiceBridge().initializeGuiceBridge(locator);
        Injector injector = Guice.createInjector(new GuiceMessageModule());
        GuiceIntoHK2Bridge guiceBridge = locator.getService(GuiceIntoHK2Bridge.class);
        guiceBridge.bridgeGuiceInjector(injector);

        // Add my HK2 Service
        ServiceLocatorUtilities.addClasses(locator, HK2Service.class);

        // Look up HK2 service. If this lookup works, `@Inject` in Jersey should.
        HK2Service service = locator.getService(HK2Service.class);
        service.printMessage("peeskillet");
    }
}

这会打印出"Hello, peeskillet"。请参阅下面的评论 main 在 Jersey 应用程序中获取 ServiceLocator 的方法。如果您对ServiceLocator 不熟悉，您使用AbstractBinder 添加的所有绑定也将被放入服务定位器上下文中，因此您不必像上面使用@ 那样显式添加类987654331@。