Andoid 总线设计 (三)

具体的代码设计：

标记注解 用于执行方法上面
@Retention(RetentionPolicy.RUNTIME)
@Target(ElementType.METHOD)
public @interface Subscriber {
SubscriberType type();
}

标记执行类型 同步或者异步
public enum SubscriberType {
ASYN, SYNC;
}

SubscribeMethod 保存目标函数的一个类：
里面有：
//执行对象
private Object object;
// 方法
private Method method;
// 参数 (只支持一个参数的方法)
private Class<> parameters;
//执行类型
private SubscriberType subscriberType;

省 get set

DistributeHandler 是一个分发接口

AsynDistributeHandler 异步分发实现。
SyncDistributeHandler 同步分发实现。

public interface DistributeHandler {
void handEvent(Object parameter);
}

---

public class AsynDistributeHandler implements DistributeHandler {
public AsynDistributeHandler(SubscribeMethod subscribeMethod) {
this.subscribeMethod = subscribeMethod;
}

private SubscribeMethod subscribeMethod = null;@Overridepublic void handEvent(final Object parameter) {    new Thread(new Runnable() {        @Override        public void run() {            ReflectionHelper.invokeSubscribeMethod(subscribeMethod, parameter);        }    }).start();}

}

---

public class SyncDistributeHandler implements DistributeHandler {

private SubscribeMethod subscribeMethod = null;public SyncDistributeHandler(SubscribeMethod subscribeMethod) {    this.subscribeMethod = subscribeMethod;}@Overridepublic void handEvent(Object parameter) {    ReflectionHelper.invokeSubscribeMethod(subscribeMethod, parameter);}

}

分发处理 管理类
DistributeManeger 管理事件的分发

public class DistributeManeger {
private DistributeHandler distributeHandler;

/** * 分发事件 * * @param parameter */public void post(Object parameter) {    List<SubscribeMethod> subscribeMethods = ReflectionHelper.getTypeSubscribeMethods(parameter, EventBus.getInstance().getSubscribeMethodList());    for (SubscribeMethod subscribeMethod : subscribeMethods) {        if (subscribeMethod.getSubscriberType().equals(SubscriberType.ASYN)) {            distributeHandler = new AsynDistributeHandler(subscribeMethod);            distributeHandler.handEvent(parameter);        } else if (subscribeMethod.getSubscriberType().equals(SubscriberType.SYNC)) {            distributeHandler = new SyncDistributeHandler(subscribeMethod);            distributeHandler.handEvent(parameter);        }    }}/** * 注销 * * @param obj */public void unregister(Object obj) {    List<SubscribeMethod> subscribeMethods = ReflectionHelper.getTypeObjSubscribeMethod(obj, EventBus.getInstance().getSubscribeMethodList());    for (SubscribeMethod subscribeMethod : subscribeMethods) {        EventBus.getInstance().getSubscribeMethodList().remove(subscribeMethod);    }}

}

反射处理类 ReflectionHelper :

public class ReflectionHelper {
private static final String TAG = ReflectionHelper.class.getSimpleName();

/** * 获取 含有 @Subscriber 的方法 * * @param obj * @param subscribeMethodList */public static void getSubscribeMethods(Object obj, List<SubscribeMethod> subscribeMethodList) {    Class clazz = obj.getClass();    Method[] methods = clazz.getDeclaredMethods();    for (Method method : methods) {        if (method.isAnnotationPresent(Subscriber.class) && method.getParameterTypes().length == 1) {            Subscriber subscriber = method.getAnnotation(Subscriber.class);            Class parameters = method.getParameterTypes()[0];            SubscribeMethod subscribeMethod = new SubscribeMethod();            subscribeMethod.setObject(obj);            subscribeMethod.setMethod(method);            subscribeMethod.setParameters(parameters);            subscribeMethod.setSubscriberType(subscriber.type());            subscribeMethodList.add(subscribeMethod);        }    }}/** * * 根据 Post 函数里面的参数 获取 有这些参数的方法 * @param parameter * @param subscribeMethodList * @return */public static List<SubscribeMethod> getTypeSubscribeMethods(Object parameter, List<SubscribeMethod> subscribeMethodList) {    Class<?> clazz = parameter.getClass();    List<SubscribeMethod> typeSubscribeMethodList = new ArrayList<>();    for (SubscribeMethod subMethod : subscribeMethodList) {        if (clazz.equals(subMethod.getParameters())) {            typeSubscribeMethodList.add(subMethod);        }    }    return typeSubscribeMethodList;}/** * 执行 * * @param subscribeMethod * @param parameter */public static void invokeSubscribeMethod(SubscribeMethod subscribeMethod, Object parameter) {    Method method = subscribeMethod.getMethod();    Object object = subscribeMethod.getObject();    try {        method.setAccessible(true);        method.invoke(object, parameter);    } catch (IllegalAccessException e) {        e.printStackTrace();    } catch (InvocationTargetException e) {        e.printStackTrace();    }}/** * 根据 obj 获取 列表 * * @param obj * @param subscribeMethodList * @return */public static List<SubscribeMethod> getTypeObjSubscribeMethod(Object obj, List<SubscribeMethod> subscribeMethodList) {    List<SubscribeMethod> typeSubscribeMethodList = new ArrayList<>();    for (SubscribeMethod subMethod : subscribeMethodList) {        if (obj.equals(subMethod.getObject())) {            typeSubscribeMethodList.add(subMethod);        }    }    return typeSubscribeMethodList;}

}

EventBus 事件处理类：

public class EventBus {
private static EventBus instance;

private List<SubscribeMethod> subscribeMethodList = new ArrayList<>();private DistributeManeger distributeManeger = new DistributeManeger();/** * @return */public static EventBus getInstance() {    if (null == instance)        newInstance();    return instance;}/** * 初始化实例 */private static synchronized void newInstance() {    if (null == instance) {        instance = new EventBus();    }}/** * 注册某对象 * 1 . 获取含有注解的方法 参数 * * @param obj */public void register(Object obj) {    ReflectionHelper.getSubscribeMethods(obj, subscribeMethodList);}/** * 发送事件 * * @param obj */public void post(Object obj) {    distributeManeger.post(obj);}/** * 反注册某对象 * * @param obj */public void unregister(Object obj) {    distributeManeger.unregister(obj);}/** * * @return */public List<SubscribeMethod> getSubscribeMethodList() {    return subscribeMethodList;}

}

好到此 代码写完了 接下来就是 测试及使用 最后总结一下。