Question

我正在尝试通过界面使用Play / Guice依赖注入：

public interface IService {
    Result handleRequest();
}

public Service implements IService {
    @Override
    public Result handleRequest() {
        ...
        return result;
    }
}

public class Controller {
    private final IService service;

    @Inject
    public Controller(IService service) {
        this.service = service;
    }
}

我得到：

play.api.UnexpectedException: Unexpected exception[CreationException: Unable to create injector, see the following errors:

1.) No implementation for IService was bound.

如果我将控制器类更改为不使用接口，则可以正常工作：

public class Controller {
    private final Service service;

    @Inject
    public Controller(Service service) {
        this.service = service;
    }
}

我如何使其与接口配合使用，以便它找到具体的Service类？

Answer 1

您可以像这样使用guice注释@ImplementedBy：

import com.google.inject.ImplementedBy;

@ImplementedBy(Service.class)
public interface IService {
    Result handleRequest();
}

或者您可以使用如下模块：

import com.google.inject.AbstractModule;

public class ServiceModule extends AbstractModule {

    protected void configure() {
        bind(IService.class).to(Service.class);
    }
}

然后在application.conf play.modules.enabled += "modules.ServiceModule"

中注册它们

具有接口的播放和引导依赖注入

1 个答案: