HK2等效辅助注射加FactoryModuleBuilder

Question

由于迁移到泽西2，我需要从guice迁移到HK2。对于我的一些依赖项，我有一种辅助注入方法，但我无法在HK2中实现它。看起来它应该通过自定义注入解析器来解决，但我不太明白是怎么解决的。这些例子对我来说不够清楚。

这是在Guice上的样子：

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){
      ...
   }
}

我如何在HK2上实现这一点？

Answer 1

在发布了这个问题之后，我想到这样做：

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

有一个盖斯桥 :-D

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

下面是一个使用Guice3.0和HK2 2.3.0的示例(它与Jersey2.13捆绑在一起)。这只是一个独立的，但它应该工作在泽西岛的环境一样。

Guice课程

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，它注入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());
    }
}

Main

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");
    }
}

这个打印出了"Hello, peeskillet"。请参见下面的main方法，以便在泽西岛应用程序中获得ServiceLocator。如果您对ServiceLocator不熟悉，那么使用AbstractBinder添加的所有绑定也将被放入服务定位器上下文中，因此您不必显式地添加类，因为我在前面介绍了HK2Service。