public interface Human {

    public void goHome();

}

Human：人类，下班了该回家啦

public interface Car {

    void start();

    void stop();

    void turnLeft();

    void turnRight();

}

Car：汽车，可以启动、停止、左转、右转

public class AudiCar implements Car{

    public void start() {

        System.out.println(this.getClass().getSimpleName() + ": start !!!");

    }

    public void stop() {

        System.out.println(this.getClass().getSimpleName() + ": stop !!!");

    }

    public void turnLeft() {

        System.out.println(this.getClass().getSimpleName() + ": turnLeft !!!");

    }

    public void turnRight() {

        System.out.println(this.getClass().getSimpleName() + ": turnRight !!!");

    }

}

AudiCar：奥迪汽车，实现Car

public class BuickCar implements Car{

    public void start() {

        System.out.println(this.getClass().getSimpleName() + ": start !!!");

    }

    public void stop() {

        System.out.println(this.getClass().getSimpleName() + ": stop !!!");

    }

    public void turnLeft() {

        System.out.println(this.getClass().getSimpleName() + ": turnLeft !!!");

    }

    public void turnRight() {

        System.out.println(this.getClass().getSimpleName() + ": turnRight !!!");

    }

}

BuickCar：别克汽车，实现Car

public abstract class HumenWithCar implements Human{

    protected final Car car;

    public HumenWithCar(Car car) {

        this.car = car;

    }

    public abstract void goHome();

}

HumenWithCar有车一族，实现Human，拥有Car属性

public class Zhang3Human extends HumenWithCar{

    public Zhang3Human(Car car) {

        super(car);

    }

    public void goHome() {

        car.start();

        car.turnLeft();

        car.stop();

    }

}

Zhang3Human：张三，有车一族

public class Li4Human extends HumenWithCar{

    public Li4Human(Car car) {

        super(car);

    }

    public void goHome() {

        car.start();

        car.turnRight();

        car.stop();

    }

}

Li4Human：李四，有车一族

public class IocContrainner {

    /**

     * 用来存储beans，String为bean的id，Object为bean本身

     */

    private final Map<String, Object> beans = new HashMap<String, Object>();

    /**

     * 根据beanId获取一个bean

     * @param beanId beanId

     * @return 返回bean

     */

    public Object getBean(String beanId) {

        return beans.get(beanId);

    }

    /**

     * 委托IoC容器创建一个bean

     * @param clazz 要创建的bean的class

     * @param beanId beanId

     * @param paramBeanIds 要创建的bean的class的构造方法所依赖的bean

     */

    public void registerBean(Class<?> clazz, String beanId, String... paramBeanIds)  {

        Object[] paramValues = new Object[paramBeanIds.length];

        for (int i = 0; i < paramBeanIds.length; i++) {

            Object paramValue = getBean(paramBeanIds[i]);

            if (paramValue == null) {

                throw new RuntimeException("Can't find bean of id: " + paramBeanIds[i]);

            }

            paramValues[i] = paramValue;

        }

        Object bean = null;

        // 获取并循环所有的构造方法

        Constructor<?>[] constructors = clazz.getConstructors();

        for (Constructor<?> constructor : constructors) {

            try {

                bean = constructor.newInstance(paramValues);

            } catch (InstantiationException e) {

            } catch (IllegalAccessException e) {

            } catch (InvocationTargetException e) {

            }

        }

        if (bean == null) {

            throw new RuntimeException("找不到合适的构造方法：" + paramBeanIds);

        }

        beans.put(beanId, bean);

    }

}

public class IocContrainnerTest {

    private final IocContrainner iocContrainner = new IocContrainner();

    @Before

    public void before() {

        iocContrainner.registerBean(AudiCar.class, "audi");

        iocContrainner.registerBean(PorscheCar.class, "porsche");

        iocContrainner.registerBean(BuickCar.class, "buick");

        iocContrainner.registerBean(Zhang3Human.class, "zhang3", "audi");

        iocContrainner.registerBean(Li4Human.class, "li4", "porsche");

    }

    @Test

    public void test() {

        Human zhang3 = (Human) iocContrainner.getBean("zhang3");

        zhang3.goHome();

        Human li4 = (Human) iocContrainner.getBean("li4");

        li4.goHome();

    }

}