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import com.google.inject.*;
import com.google.inject.privatemodules.PrivateModule;

import static java.lang.annotation.ElementType.*;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
import java.util.Date;

public class RobotLegsProblem2 {


    public static void main(String[] args) {
        Injector injector = Guice.createInjector(new AbstractModule() {
            @Override
            protected void configure() {
                // global stuff
                // same to all
                bind(Driveline.class).to(FrontWheelDrive.class);
                bind(Engine.class).to(DieselEngine.class);
            }
        }, new PrivateModule() {
            @Override
            protected void configurePrivateBindings() {
                // private Module is different story
                // Bind car annotated with blue and expose it
                bind(Car.class).annotatedWith(Blue.class).to(Car.class);
                expose(Car.class).annotatedWith(Blue.class);

                // What we bind in here only applies to the exposed stuff
                // i.e. the exposed car from this module will get this injected
                // where stuff in regular module (Engine,Driveline) is "inherited" - it is global
                bind(Transmission.class).to(AutomaticTransmission.class);
            }
        }, new PrivateModule() {
            @Override
            protected void configurePrivateBindings() {
                bind(Car.class).annotatedWith(Red.class).to(Car.class);
                expose(Car.class).annotatedWith(Red.class);

                bind(Transmission.class).to(ManualTransmission.class);
               /*
                 The point is that you cannot do this with regular module i.e.
                 bind(Car.class).annotatedWith(Blue.class).to(Car.class);
                 bind(Car.class).annotatedWith(Red.class).to(Car.class);
                 now notice the dilemma
                 class Car{
                 @Inject Transmission transmission;
                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
                 You cannot solve this by
                 @Inject @Blue @Red Transmission transmission;
                 or
                 bind(Transmission.class).to(AutomaticTransmission.class).ifParentAnnotatedWith(Blue.class)
                 bind(Transmission.class).to(ManualTransmission.class).ifParentAnnotatedWith(Red.class)
                 but with private modules you can get this functionality
                 */
            }
        });

        Car blueCar = injector.getInstance(Key.get(Car.class, Blue.class));
        System.out.println("Blue car transmission: " + blueCar.getTransmission());

        Car redCar = injector.getInstance(Key.get(Car.class, Red.class));
        System.out.println("Red car transmission: " + redCar.getTransmission());

    }


}

@Retention(RetentionPolicy.RUNTIME)
@Target({FIELD, PARAMETER, METHOD})
@BindingAnnotation
        @interface Blue {
}

@Retention(RetentionPolicy.RUNTIME)
@Target({FIELD, PARAMETER, METHOD})
@BindingAnnotation
        @interface Red {
}

class Car {

    private final Engine engine;
    private final Transmission transmission;
    private final Driveline driveline;

    @Inject
    public Car(Engine engine, Transmission transmission, Driveline driveline) {
        this.engine = engine;
        this.transmission = transmission;
        this.driveline = driveline;;
    }

    public Driveline getDriveline() {
        return driveline;
    }

    public Engine getEngine() {
        return engine;
    }

    public Transmission getTransmission() {
        return transmission;
    }
}


interface Transmission {
}

class AutomaticTransmission implements Transmission {
}

class ManualTransmission implements Transmission {
}

interface Engine {
}

class DieselEngine implements Engine {
}

class PetrolEngine implements Engine {
}

interface Driveline {
}

class FourWheelDrive implements Driveline {
}

class FrontWheelDrive implements Driveline {
}

class RearWheelDrive implements Driveline {
}