复习
经过前面的文章，我们知道注解处理后重新生成的文件，我们再来复习下
- 被Route注解的会生成类似下面这样的类
如果是IProvider类型的，会生成类似下面的类
- 如果是 IInterceptor 类型的，会生成类似下面的类，其实 IInterceptor 也是 IProvider类的子类
- 可以用Class 来进行路由，是因为生成了类似下面这样的类，path就是类的全限定名。
- 收集每个组的类。
ARouter.init
路由初始化
ARouter.init(getApplication());
public static void init(Application application) {
if (!hasInit) {
logger = _ARouter.logger;
_ARouter.logger.info(Consts.TAG, "ARouter init start.");
hasInit = _ARouter.init(application); // 初始化 _ARouter
if (hasInit) {
_ARouter.afterInit();// 初始化后，获取 InterceptorService，，对拦截做统一处理
}
_ARouter.logger.info(Consts.TAG, "ARouter init over.");
}
}
protected static synchronized boolean init(Application application) {
mContext = application;
LogisticsCenter.init(mContext, executor);
logger.info(Consts.TAG, "ARouter init success!");
hasInit = true;
mHandler = new Handler(Looper.getMainLooper());
return true;
}
LogisticsCenter.init
private static void loadRouterMap() {
registerByPlugin = false;
// auto generate register code by gradle plugin: arouter-auto-register
// looks like below:
// registerRouteRoot(new ARouter..Root..modulejava());
// registerRouteRoot(new ARouter..Root..modulekotlin());
}
源码中是上面这样的，之前为了收集路由信息，程序启动后会扫描dex文件，不过这样会影响启动速度，不过后来经过 arouter-register 插件的插桩的处理，会扫描 jar 包中满足条件的类，收集后就会变成下面这样
private static void loadRouterMap()
{
registerByPlugin = false;
register("com.alibaba.android.arouter.routes.ARouter$$Root$$modulejava");
register("com.alibaba.android.arouter.routes.ARouter$$Root$$arouterapi");
register("com.alibaba.android.arouter.routes.ARouter$$Interceptors$$modulejava");
register("com.alibaba.android.arouter.routes.ARouter$$Providers$$modulejava");
register("com.alibaba.android.arouter.routes.ARouter$$Providers$$arouterapi");
}
在看下面之前线来看看 Warehouse 类，里面存了所有的路由信息。
class Warehouse {
// Cache route and metas
static Map<String, Class<? extends IRouteGroup>> groupsIndex = new HashMap<>();
static Map<String, RouteMeta> routes = new HashMap<>();
// Cache provider
static Map<Class, IProvider> providers = new HashMap<>();
static Map<String, RouteMeta> providersIndex = new HashMap<>();
// Cache interceptor
static Map<Integer, Class<? extends IInterceptor>> interceptorsIndex = new UniqueKeyTreeMap<>("More than one interceptors use same priority [%s]");
static List<IInterceptor> interceptors = new ArrayList<>();
static void clear() {
routes.clear();
groupsIndex.clear();
providers.clear();
providersIndex.clear();
interceptors.clear();
interceptorsIndex.clear();
}
}
很简单，就是注册我们指定的类。
private static void register(String className) {
if (!TextUtils.isEmpty(className)) {
try {
Class<?> clazz = Class.forName(className);
Object obj = clazz.getConstructor().newInstance(); //实例化一个对象
if (obj instanceof IRouteRoot) {
registerRouteRoot((IRouteRoot) obj);
} else if (obj instanceof IProviderGroup) {
registerProvider((IProviderGroup) obj);
} else if (obj instanceof IInterceptorGroup) {
registerInterceptor((IInterceptorGroup) obj);
} else {
logger.info(TAG, "register failed, class name: " + className
+ " should implements one of IRouteRoot/IProviderGroup/IInterceptorGroup.");
}
} catch (Exception e) {
logger.error(TAG,"register class error:" + className, e);
}
}
}
private static void registerRouteRoot(IRouteRoot routeRoot) {
markRegisteredByPlugin(); // 会改变 registerByPlugin 为true，这样后面就不会扫描dex了。
if (routeRoot != null) {
routeRoot.loadInto(Warehouse.groupsIndex); // 对照上面的图看就很容易懂了。
}
}
private static void registerProvider(IProviderGroup providerGroup) {
markRegisteredByPlugin();
if (providerGroup != null) {
providerGroup.loadInto(Warehouse.providersIndex);
}
}
private static void registerInterceptor(IInterceptorGroup interceptorGroup) {
markRegisteredByPlugin();
if (interceptorGroup != null) {
interceptorGroup.loadInto(Warehouse.interceptorsIndex);
}
}
经过 loadRouterMap()方法的执行，已经收集了所有的路由信息，下面就是根据path路由到其他类的操作了。
navigation
public <T> T navigation(Class<? extends T> service) {
return _ARouter.getInstance().navigation(service);
}
我们先对 navigation 源码分析，因为后面build里面还会调用 navigation ，在demo中，有个HelloService，有一个直接的子类 HelloServiceImpl，想要得到 HelloServiceImpl ，可以 用 navigation(HelloService.class)得到，也可以用path得到。
public interface HelloService extends IProvider {
void sayHello(String name);
}
@Route(path = "/yourservicegroupname/hello")
public class HelloServiceImpl implements HelloService {
Context mContext;
@Override
public void sayHello(String name) {
Toast.makeText(mContext, "Hello " + name, Toast.LENGTH_SHORT).show();
}
@Override
public void init(Context context) {
mContext = context;
Log.e("testService", HelloService.class.getName() + " has init.");
}
}
protected <T> T navigation(Class<? extends T> service) {
try {
Postcard postcard = LogisticsCenter.buildProvider(service.getName());
// Compatible 1.0.5 compiler sdk.
// Earlier versions did not use the fully qualified name to get the service
if (null == postcard) {
// No service, or this service in old version.
postcard = LogisticsCenter.buildProvider(service.getSimpleName());
}
if (null == postcard) {
return null;
}
// Set application to postcard.
postcard.setContext(mContext);
LogisticsCenter.completion(postcard);
return (T) postcard.getProvider();
} catch (NoRouteFoundException ex) {
logger.warning(Consts.TAG, ex.getMessage());
return null;
}
}
从Warehouse.providersIndex 的HashMap中根据全限定名得到 RouteMeta
public static Postcard buildProvider(String serviceName) {
RouteMeta meta = Warehouse.providersIndex.get(serviceName);
if (null == meta) {
return null;
} else {
return new Postcard(meta.getPath(), meta.getGroup());
}
}
刚刚new 出来的 Postcard 只含有 path 和Group，还需要对其他信息进行补充。先从 routes 缓存中根据path获取 RouteMeta，如果缓存中没有，可以动态添加。
如果缓存中有了，就把数据填充到 Postcard
public synchronized static void completion(Postcard postcard) {
if (null == postcard) {
throw new NoRouteFoundException(TAG + "No postcard!");
}
// 先从缓存类找
RouteMeta routeMeta = Warehouse.routes.get(postcard.getPath());
if (null == routeMeta) {
// Maybe its does't exist, or didn't load.
// 缓存里没有
// 可以动态添加，但是先要把group添加进来
if (!Warehouse.groupsIndex.containsKey(postcard.getGroup())) {
throw new NoRouteFoundException(TAG + "There is no route match the path [" + postcard.getPath() + "], in group [" + postcard.getGroup() + "]");
} else {
// Load route and cache it into memory, then delete from metas.
try {
if (ARouter.debuggable()) {
logger.debug(TAG, String.format(Locale.getDefault(), "The group [%s] starts loading, trigger by [%s]", postcard.getGroup(), postcard.getPath()));
}
// 动态添加
addRouteGroupDynamic(postcard.getGroup(), null);
if (ARouter.debuggable()) {
logger.debug(TAG, String.format(Locale.getDefault(), "The group [%s] has already been loaded, trigger by [%s]", postcard.getGroup(), postcard.getPath()));
}
} catch (Exception e) {
throw new HandlerException(TAG + "Fatal exception when loading group meta. [" + e.getMessage() + "]");
}
completion(postcard); // Reload
}
} else {
// 从缓存取数据
postcard.setDestination(routeMeta.getDestination()); // 路由目标类
postcard.setType(routeMeta.getType()); // 路由的类型 RouteType ，可以是 ACTIVITY、SERVICE、PROVIDER 、CONTENT_PROVIDER、FRAGMENT等
postcard.setPriority(routeMeta.getPriority()); // 权限值
postcard.setExtra(routeMeta.getExtra()); // 额外的信息
Uri rawUri = postcard.getUri();
if (null != rawUri) { // Try to set params into bundle.
Map<String, String> resultMap = TextUtils.splitQueryParameters(rawUri);
Map<String, Integer> paramsType = routeMeta.getParamsType();
if (MapUtils.isNotEmpty(paramsType)) {
// Set value by its type, just for params which annotation by @Param
for (Map.Entry<String, Integer> params : paramsType.entrySet()) {
setValue(postcard,
params.getValue(),
params.getKey(),
resultMap.get(params.getKey()));
}
// Save params name which need auto inject.
postcard.getExtras().putStringArray(ARouter.AUTO_INJECT, paramsType.keySet().toArray(new String[]{}));
}
// Save raw uri
postcard.withString(ARouter.RAW_URI, rawUri.toString());
}
switch (routeMeta.getType()) {
case PROVIDER: // if the route is provider, should find its instance
// Its provider, so it must implement IProvider
Class<? extends IProvider> providerMeta = (Class<? extends IProvider>) routeMeta.getDestination();
IProvider instance = Warehouse.providers.get(providerMeta); // 从缓存中取
if (null == instance) { // There's no instance of this provider
// 没有缓存
IProvider provider;
try {
provider = providerMeta.getConstructor().newInstance();
provider.init(mContext);
Warehouse.providers.put(providerMeta, provider); // 放到缓存中
instance = provider;
} catch (Exception e) {
logger.error(TAG, "Init provider failed!", e);
throw new HandlerException("Init provider failed!");
}
}
postcard.setProvider(instance); // 拿到了实例对象
postcard.greenChannel(); // 绿色通道， Provider不受拦截器的影响
break;
case FRAGMENT:
postcard.greenChannel(); // Fragment 类型也走绿色通道，不受拦截器的影响
default:
break;
}
}
}
build
public Postcard build(String path) {
return _ARouter.getInstance().build(path);
}
我们用build进行源码分析，首先
protected Postcard build(String path) {
if (TextUtils.isEmpty(path)) {
throw new HandlerException(Consts.TAG + "Parameter is invalid!");
} else {
PathReplaceService pService = ARouter.getInstance().navigation(PathReplaceService.class);
if (null != pService) {
path = pService.forString(path);
}
// 如果有PathReplaceService ，这里的path已经经过PathReplaceService， afterReplace就是为true，后面就不要到 PathReplaceService了
return build(path, extractGroup(path), true);
}
}
如果实现 PathReplaceService ，可以对path进行拦截与修改。
public interface PathReplaceService extends IProvider {
/**
* For normal path.
*
* @param path raw path
*/
String forString(String path);
/**
* For uri type.
*
* @param uri raw uri
*/
Uri forUri(Uri uri);
}
protected Postcard build(String path, String group, Boolean afterReplace) {
if (TextUtils.isEmpty(path) || TextUtils.isEmpty(group)) {
throw new HandlerException(Consts.TAG + "Parameter is invalid!");
} else {
if (!afterReplace) {
PathReplaceService pService = ARouter.getInstance().navigation(PathReplaceService.class);
if (null != pService) {
path = pService.forString(path);
}
}
return new Postcard(path, group);
}
}
protected Object navigation(final Context context, final Postcard postcard, final int requestCode, final NavigationCallback callback) {
// 在 navigation之前 我们还有一次机会修改Postcard，是否需要被路由
PretreatmentService pretreatmentService = ARouter.getInstance().navigation(PretreatmentService.class);
if (null != pretreatmentService && !pretreatmentService.onPretreatment(context, postcard)) {
// 条件不满足，不再 navigation
// Pretreatment failed, navigation canceled.
return null;
}
// Set context to postcard.
postcard.setContext(null == context ? mContext : context);
try {
LogisticsCenter.completion(postcard); // 把数据填充到 Postcard
} catch (NoRouteFoundException ex) {
...........
if (null != callback) {
callback.onLost(postcard);//给出回调
} else {
// No callback for this invoke, then we use the global degrade service.
DegradeService degradeService = ARouter.getInstance().navigation(DegradeService.class);
if (null != degradeService) {
degradeService.onLost(context, postcard);
}
}
return null;
}
if (null != callback) {
callback.onFound(postcard); //给出回调，已经找到 postcard
}
// Arouter init后，会获取 InterceptorService
if (!postcard.isGreenChannel()) { // It must be run in async thread, maybe interceptor cost too mush time made ANR.
//fragment、provide都是绿色通道
interceptorService.doInterceptions(postcard, new InterceptorCallback() {
/**
* Continue process
*
* @param postcard route meta
*/
@Override
public void onContinue(Postcard postcard) {
_navigation(postcard, requestCode, callback);
}
/**
* Interrupt process, pipeline will be destory when this method called.
*
* @param exception Reson of interrupt.
*/
@Override
public void onInterrupt(Throwable exception) {
if (null != callback) {
callback.onInterrupt(postcard);
}
logger.info(Consts.TAG, "Navigation failed, termination by interceptor : " + exception.getMessage());
}
});
} else {
return _navigation(postcard, requestCode, callback);
}
return null;
}
private Object _navigation(final Postcard postcard, final int requestCode, final NavigationCallback callback) {
final Context currentContext = postcard.getContext();
switch (postcard.getType()) {
case ACTIVITY:
// 和我们平时用Intetn打开Activity一样
// Build intent
final Intent intent = new Intent(currentContext, postcard.getDestination());
intent.putExtras(postcard.getExtras()); // 额外的参数
// Set flags.
int flags = postcard.getFlags();
if (0 != flags) {
intent.setFlags(flags);
}
// Non activity, need FLAG_ACTIVITY_NEW_TASK
if (!(currentContext instanceof Activity)) {
intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
}
// Set Actions
String action = postcard.getAction();
if (!TextUtils.isEmpty(action)) {
intent.setAction(action);
}
// Navigation in main looper.
runInMainThread(new Runnable() {
@Override
public void run() {
startActivity(requestCode, currentContext, intent, postcard, callback);
}
});
break;
case PROVIDER:
return postcard.getProvider();// 如果是provide，之间返回
case BOARDCAST:
case CONTENT_PROVIDER:
case FRAGMENT:
Class<?> fragmentMeta = postcard.getDestination();
try {
Object instance = fragmentMeta.getConstructor().newInstance();
if (instance instanceof Fragment) {
((Fragment) instance).setArguments(postcard.getExtras());
} else if (instance instanceof android.support.v4.app.Fragment) {
((android.support.v4.app.Fragment) instance).setArguments(postcard.getExtras());
}
return instance;
} catch (Exception ex) {
logger.error(Consts.TAG, "Fetch fragment instance error, " + TextUtils.formatStackTrace(ex.getStackTrace()));
}
case METHOD:
case SERVICE:
default:
return null;
}
return null;
}
InterceptorService
@Route(path = "/arouter/service/interceptor")
public class InterceptorServiceImpl implements InterceptorService
先到子线程中初始化，按照顺序执行我们定义的拦截器，因为拦截方法中可能有耗时操作，引起ANR，所以放在子线程中执行拦截操作。
@Override
public void init(final Context context) {
LogisticsCenter.executor.execute(new Runnable() {
@Override
public void run() {
if (MapUtils.isNotEmpty(Warehouse.interceptorsIndex)) {
for (Map.Entry<Integer, Class<? extends IInterceptor>> entry : Warehouse.interceptorsIndex.entrySet()) {
Class<? extends IInterceptor> interceptorClass = entry.getValue();
try {
IInterceptor iInterceptor = interceptorClass.getConstructor().newInstance();
iInterceptor.init(context);
Warehouse.interceptors.add(iInterceptor);
} catch (Exception ex) {
throw new HandlerException(TAG + "ARouter init interceptor error! name = [" + interceptorClass.getName() + "], reason = [" + ex.getMessage() + "]");
}
}
interceptorHasInit = true;
logger.info(TAG, "ARouter interceptors init over.");
synchronized (interceptorInitLock) {
interceptorInitLock.notifyAll();
}
}
}
});
}
@Override
public void doInterceptions(final Postcard postcard, final InterceptorCallback callback) {
if (MapUtils.isNotEmpty(Warehouse.interceptorsIndex)) {
checkInterceptorsInitStatus();
if (!interceptorHasInit) {
callback.onInterrupt(new HandlerException("Interceptors initialization takes too much time."));
return;
}
LogisticsCenter.executor.execute(new Runnable() {
@Override
public void run() {
//
CancelableCountDownLatch interceptorCounter = new CancelableCountDownLatch(Warehouse.interceptors.size());
try {
_execute(0, interceptorCounter, postcard);
interceptorCounter.await(postcard.getTimeout(), TimeUnit.SECONDS);
if (interceptorCounter.getCount() > 0) { // Cancel the navigation this time, if it hasn't return anythings.
callback.onInterrupt(new HandlerException("The interceptor processing timed out."));
} else if (null != postcard.getTag()) { // Maybe some exception in the tag.
callback.onInterrupt((Throwable) postcard.getTag());
} else {
callback.onContinue(postcard);
}
} catch (Exception e) {
callback.onInterrupt(e);
}
}
});
} else {
callback.onContinue(postcard);
}
}
private static void _execute(final int index, final CancelableCountDownLatch counter, final Postcard postcard) {
if (index < Warehouse.interceptors.size()) {
// 我们自定义的拦截器
IInterceptor iInterceptor = Warehouse.interceptors.get(index);
iInterceptor.process(postcard, new InterceptorCallback() {
@Override
public void onContinue(Postcard postcard) {
// Last interceptor excute over with no exception.
counter.countDown();
// 处理完成，交给下一个拦截器
_execute(index + 1, counter, postcard); // When counter is down, it will be execute continue ,but index bigger than interceptors size, then U know.
}
@Override
public void onInterrupt(Throwable exception) {
// Last interceptor execute over with fatal exception.
postcard.setTag(null == exception ? new HandlerException("No message.") : exception); // save the exception message for backup.
counter.cancel();
// Be attention, maybe the thread in callback has been changed,
// then the catch block(L207) will be invalid.
// The worst is the thread changed to main thread, then the app will be crash, if you throw this exception!
// if (!Looper.getMainLooper().equals(Looper.myLooper())) { // You shouldn't throw the exception if the thread is main thread.
// throw new HandlerException(exception.getMessage());
// }
}
});
}
}
inject
依赖注入，经过 Autowired 注解的 类，会自动生成类似下面这样的类，先获取Test3Activity这个类名，利用这个类名追加 ` ARouter$$Autowired,会得到
Test3ActivityARouter$$Autowired 这个类，实例化这个对象，调用这个对象中的inject方法，参数就是 Test3Activity 对象。
调用inject会
public void inject(Object thiz) {
_ARouter.inject(thiz);
}
static void inject(Object thiz) {
AutowiredService autowiredService = ((AutowiredService) ARouter.getInstance().build("/arouter/service/autowired").navigation());
if (null != autowiredService) {
autowiredService.autowire(thiz);
}
}
@Route(path = "/arouter/service/autowired")
public class AutowiredServiceImpl implements AutowiredService {
private LruCache<String, ISyringe> classCache;
private List<String> blackList;
@Override
public void init(Context context) {
classCache = new LruCache<>(50);
blackList = new ArrayList<>();
}
@Override
public void autowire(Object instance) {
doInject(instance, null);
}
/**
* Recursive injection
*
* @param instance who call me.
* @param parent parent of me.
*/
private void doInject(Object instance, Class<?> parent) {
Class<?> clazz = null == parent ? instance.getClass() : parent;
ISyringe syringe = getSyringe(clazz);
if (null != syringe) {
syringe.inject(instance);
}
Class<?> superClazz = clazz.getSuperclass();
// has parent and its not the class of framework.
if (null != superClazz && !superClazz.getName().startsWith("android")) {
doInject(instance, superClazz);
}
}
private ISyringe getSyringe(Class<?> clazz) {
String className = clazz.getName();
try {
if (!blackList.contains(className)) {
ISyringe syringeHelper = classCache.get(className);
if (null == syringeHelper) { // No cache.
syringeHelper = (ISyringe) Class.forName(clazz.getName() + SUFFIX_AUTOWIRED).getConstructor().newInstance();
}
classCache.put(className, syringeHelper);
return syringeHelper;
}
} catch (Exception e) {
blackList.add(className); // This instance need not autowired.
}
return null;
}
}
