java - 使用 Spring IOC (DI) 解决 "Robot legs"p‌r‌o‌b‌l‌e‌m

Question

使用 Guice，可以执行以下操作:

interface Leg {}

_

class LeftLeg implements Leg {
    public String toString() {
        return "LeftLeg";
    }
}

_

class RightLeg implements Leg {
    public String toString() {
        return "RightLeg";
    }
}

_

class Robot {
    final Leg leftLeg_;
    final Leg rightLeg_;

    @Inject
    Robot(@Named("left") Leg leftLeg, @Named("right") Leg rightLeg) {
        leftLeg_ = leftLeg;
        rightLeg_ = rightLeg;
    }

    public String toString() {
        return "leftLeg_=" + leftLeg_ + ", rightLeg_=" + rightLeg_;
    }
}

_

class RobotTest {
    @Test
    public void t1() throws Exception {
        Injector inj = Guice.createInjector(new AnGuiceModule());
        Robot r = inj.getInstance(Robot.class);
        assertEquals(r.toString(), "leftLeg_=LeftLeg, rightLeg_=RightLeg");
    }
}

_

class AnGuiceModule extends AbstractModule {
    protected void configure() {
        bind(Leg.class).annotatedWith(Names.named("left")).to(LeftLeg.class);
        bind(Leg.class).annotatedWith(Names.named("right")).to(RightLeg.class);
    }
}

如何在不使用 XML 配置的情况下使用 JSR-330(可选)注释和 JavaConfig 在 Spring 3.x(3.1.x 或 3.2)中实现相同的功能？

Answer 1

接口(interface)腿{}

_

 @Component
 class LeftLeg implements Leg {
  public String toString() {
    return "LeftLeg";
  }
 }

_

@Component
class RightLeg implements Leg {
  public String toString() {
    return "RightLeg";
 }
}

_

class Robot {
  @Autowired
  Leg leftLeg_;
  @Autowired
  Leg rightLeg_;



  public String toString() {
    return "leftLeg_=" + leftLeg_ + ", rightLeg_=" + rightLeg_;
 }
}

_

@RunWith(SpringJUnit4ClassRunner.class)
class RobotTest {
  @Autowired
  Robot r;
  @Test
  public void t1() throws Exception {
     System.out.println(r);
 }
}