一、介绍
一个用于帮助 Android App 进行组件化改造的框架 —— 支持模块间的路由、通信、解耦。（官方介绍）
二、集成和使用
gradle中配置如下
android {
defaultConfig {
...
javaCompileOptions {
annotationProcessorOptions {
//在注解处理器中会获取这个AROUTER_MODULE_NAME参数
arguments = [AROUTER_MODULE_NAME: project.getName()]
}
}
}
}
dependencies {
// 替换成最新版本, 需要注意的是api
// 要与compiler匹配使用，均使用最新版可以保证兼容
implementation('com.alibaba:arouter-api:1.5.2')
annotationProcessor 'com.alibaba:arouter-compiler:1.5.2'
...
}
application中初始化sdk
public class App extends Application {
@Override
public void onCreate() {
super.onCreate();
if (BuildConfig.DEBUG) { // 这两行必须写在init之前，否则这些配置在init过程中将无效
ARouter.openLog(); // 打印日志
ARouter.openDebug(); // 开启调试模式(如果在InstantRun模式下运行，必须开启调试模式！线上版本需要关闭,否则有安全风险)
}
ARouter.init(this); // 尽可能早，推荐在Application中初始化
}
}
添加注解
// 在支持路由的页面上添加注解(必选)
// 这里的路径需要注意的是至少需要有两级，/xx/xx test为路由的分组，每个path都必须有一个分组
@Route(path = "/test/activity")
public class YourActivity extend Activity {
...
}
路由跳转
// 1. 应用内简单的跳转(通过URL跳转在'进阶用法'中)
ARouter.getInstance().build("/test/activity").navigation();
// 2. 跳转并携带参数
ARouter.getInstance().build("/test/1")
.withLong("key1", 666L)
.withString("key3", "888")
.withObject("key4", new Test("Jack", "Rose"))
.navigation();
以上是官方给出的集成方法和部分使用实例，下面的我们会根据上面的使用实例对框架源码进行分析。
三、框架初始化
可以看到示例代码是在Application中调用ARouter.init(this);进行初始化的，那么我们看下这句代码中的执行流程
ARouter.java
public static void init(Application application) {
//没有初始化过则进入判断进行初始化
if (!hasInit) {
logger = _ARouter.logger;
_ARouter.logger.info(Consts.TAG, "ARouter init start.");
//初始化
hasInit = _ARouter.init(application);
//完成初始化后进入判断执行afterInit()
if (hasInit) {
_ARouter.afterInit();
}
_ARouter.logger.info(Consts.TAG, "ARouter init over.");
}
}
_ARouter.java
protected static synchronized boolean init(Application application) {
mContext = application;
//调用LogisticsCenter的init方法，初始化的内容主要在这个方法中执行
LogisticsCenter.init(mContext, executor);
logger.info(Consts.TAG, "ARouter init success!");
hasInit = true;
mHandler = new Handler(Looper.getMainLooper());
return true;
}
LogisticsCenter.java
/**
* LogisticsCenter init, load all metas in memory. Demand initialization
*/
public synchronized static void init(Context context, ThreadPoolExecutor tpe) throws HandlerException {
mContext = context;
executor = tpe;
try {
long startInit = System.currentTimeMillis();
//如果我们使用了Arouter的gradle插件那么这个方法会使用ASM插桩自动补全代码
//load by plugin first
loadRouterMap();
if (registerByPlugin) {
//如果通过插件加载过了就打印日志
logger.info(TAG, "Load router map by arouter-auto-register plugin.");
} else {//如果没使用插件加载则执行下面的代码
Set<String> routerMap;
//每次可调试时或者版本号新增后，它都会重建路由映射
// It will rebuild router map every times when debuggable.
if (ARouter.debuggable() || PackageUtils.isNewVersion(context)) {
logger.info(TAG, "Run with debug mode or new install, rebuild router map.");
// These class was generated by arouter-compiler.
//加载根据注解生成的类，并保存到routerMap中
routerMap = ClassUtils.getFileNameByPackageName(mContext, ROUTE_ROOT_PAKCAGE);
// 如果map不是空的则更新SharedPreferences中的值
if (!routerMap.isEmpty()) {
context.getSharedPreferences(AROUTER_SP_CACHE_KEY, Context.MODE_PRIVATE).edit().putStringSet(AROUTER_SP_KEY_MAP, routerMap).apply();
}
//更新完成后则更新应用版本号
PackageUtils.updateVersion(context); // Save new version name when router map update finishes.
} else {
logger.info(TAG, "Load router map from cache.");
//不是调试模式或版本号新增则直接从SharedPreferences中加载
routerMap = new HashSet<>(context.getSharedPreferences(AROUTER_SP_CACHE_KEY, Context.MODE_PRIVATE).getStringSet(AROUTER_SP_KEY_MAP, new HashSet<String>()));
}
logger.info(TAG, "Find router map finished, map size = " + routerMap.size() + ", cost " + (System.currentTimeMillis() - startInit) + " ms.");
startInit = System.currentTimeMillis();
//遍历map获取className，根据类型调用IRouteRoot、IInterceptorGroup、IProviderGroup的loadInto方法填充Warehouse中的map集合
for (String className : routerMap) {
if (className.startsWith(ROUTE_ROOT_PAKCAGE + DOT + SDK_NAME + SEPARATOR + SUFFIX_ROOT)) {
// This one of root elements, load root.
((IRouteRoot) (Class.forName(className).getConstructor().newInstance())).loadInto(Warehouse.groupsIndex);
} else if (className.startsWith(ROUTE_ROOT_PAKCAGE + DOT + SDK_NAME + SEPARATOR + SUFFIX_INTERCEPTORS)) {
// Load interceptorMeta
((IInterceptorGroup) (Class.forName(className).getConstructor().newInstance())).loadInto(Warehouse.interceptorsIndex);
} else if (className.startsWith(ROUTE_ROOT_PAKCAGE + DOT + SDK_NAME + SEPARATOR + SUFFIX_PROVIDERS)) {
// Load providerIndex
((IProviderGroup) (Class.forName(className).getConstructor().newInstance())).loadInto(Warehouse.providersIndex);
}
}
}
logger.info(TAG, "Load root element finished, cost " + (System.currentTimeMillis() - startInit) + " ms.");
if (Warehouse.groupsIndex.size() == 0) {
logger.error(TAG, "No mapping files were found, check your configuration please!");
}
if (ARouter.debuggable()) {
logger.debug(TAG, String.format(Locale.getDefault(), "LogisticsCenter has already been loaded, GroupIndex[%d], InterceptorIndex[%d], ProviderIndex[%d]", Warehouse.groupsIndex.size(), Warehouse.interceptorsIndex.size(), Warehouse.providersIndex.size()));
}
} catch (Exception e) {
throw new HandlerException(TAG + "ARouter init logistics center exception! [" + e.getMessage() + "]");
}
}
下面接着看下ClassUtils.getFileNameByPackageName(mContext, ROUTE_ROOT_PAKCAGE);这个代码中是怎么加载所有相关类的。首先我们看到传入的包名是这个public static final String ROUTE_ROOT_PAKCAGE = "com.alibaba.android.arouter.routes";那么我也可以导工程中去看下是否在这个包下有文件生成。可以看到下面截图中对应包下确实已经自动生成了对应的类。
截取图片_20230626112114.png
先看下通过APT注解处理器生成的类的代码
ARouter$$Root$$app.java
这个类将app模块中所有注解中的group字段作为key，各个group类作为value存储起来。类名中最后的$$后的app既是模块名称，每个模块都会默认生成一个以模块名生成的存储所有路由组信息的类
/**
* DO NOT EDIT THIS FILE!!! IT WAS GENERATED BY AROUTER. */
public class ARouter$$Root$$app implements IRouteRoot {
@Override
public void loadInto(Map<String, Class<? extends IRouteGroup>> routes) {
routes.put("app_test", ARouter$$Group$$app_test.class);
routes.put("app_test1", ARouter$$Group$$app_test1.class);
}
}
ARouter$$Group$$app_test.java
这个类包含当前group中包含的path和注解此path的类的类信息和注解信息。
/**
* DO NOT EDIT THIS FILE!!! IT WAS GENERATED BY AROUTER. */
public class ARouter$$Group$$app_test implements IRouteGroup {
@Override
public void loadInto(Map<String, RouteMeta> atlas) {
atlas.put("/app_test/main", RouteMeta.build(RouteType.ACTIVITY, MainActivity.class, "/app_test/main", "app_test", null, -1, -2147483648));
atlas.put("/app_test/main2", RouteMeta.build(RouteType.ACTIVITY, MainActivity2.class, "/app_test/main2", "app_test", null, -1, -2147483648));
}
}
如果有不同的group则会生成不同group的path加载类
/**
* DO NOT EDIT THIS FILE!!! IT WAS GENERATED BY AROUTER. */
public class ARouter$$Group$$app_test1 implements IRouteGroup {
@Override
public void loadInto(Map<String, RouteMeta> atlas) {
atlas.put("/app_test1/main", RouteMeta.build(RouteType.ACTIVITY, MainActivity3.class, "/app_test1/main", "app_test1", null, -1, -2147483648));
}
}
下面接着看ClassUtils.getFileNameByPackageName方法的实现
public static Set<String> getFileNameByPackageName(Context context, final String packageName) throws PackageManager.NameNotFoundException, IOException, InterruptedException {
final Set<String> classNames = new HashSet<>();
//获取所有dex文件路径
List<String> paths = getSourcePaths(context);
final CountDownLatch parserCtl = new CountDownLatch(paths.size());
//遍历paths
for (final String path : paths) {
//线程池中执行
DefaultPoolExecutor.getInstance().execute(new Runnable() {
@Override
public void run() {
//使用DexFile加载dex文件
DexFile dexfile = null;
try {
if (path.endsWith(EXTRACTED_SUFFIX)) {
//NOT use new DexFile(path), because it will throw "permission error in /data/dalvik-cache"
dexfile = DexFile.loadDex(path, path + ".tmp", 0);
} else {
dexfile = new DexFile(path);
}
Enumeration<String> dexEntries = dexfile.entries();
while (dexEntries.hasMoreElements()) {
String className = dexEntries.nextElement();
//过滤以packageName开头的类并保存到classNames中
if (className.startsWith(packageName)) {
classNames.add(className);
}
}
} catch (Throwable ignore) {
Log.e("ARouter", "Scan map file in dex files made error.", ignore);
} finally {
if (null != dexfile) {
try {
dexfile.close();
} catch (Throwable ignore) {
}
}
parserCtl.countDown();
}
}
});
}
parserCtl.await();
Log.d(Consts.TAG, "Filter " + classNames.size() + " classes by packageName <" + packageName + ">");
return classNames;
}
上面的流程整理如下：
@Route注解的类（Fragment或Activity）会在编译时生成实现IRouteRoot的类记录本模块中的路由的group的类ARouter$$Root$$模块名,其中的loadInto方法会把所有的ARouter$$Group$$路由组名保存到map中。当应用启动后会在Application中调用init方法，这时就会拿到所有Dex文件
中所有以"com.alibaba.android.arouter.routes"开头的类名集合，然后循环遍历集合利用反射创建类的实例并调用loadInto方法,最后就把所有模块中的记录同组路由信息的类保存到了map集合中了。
四、路由跳转
初始化的工作已完成，那么通过路由跳转具体的Activity是怎么是实现的呢？以下面代码为例：
ARouter.getInstance().build("/test/activity").navigation();
ARouter.java
该方法返回一个Postcar对象
public Postcard build(String path) {
return _ARouter.getInstance().build(path);
}
_ARouter.java
先获取PathReplaceService，如果不为null则处理传进来的path。调用build方法生成一个Postcard
protected Postcard build(String path) {
if (TextUtils.isEmpty(path)) {
throw new HandlerException(Consts.TAG + "Parameter is invalid!");
} else {
//如果我们没有实现PathReplaceServices接口的类则一定为null。
PathReplaceService pService = ARouter.getInstance().navigation(PathReplaceService.class);
if (null != pService) {
path = pService.forString(path);
}
//extractGroup返回path中的group
return build(path, extractGroup(path), true);
}
}
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 {
//这里afterReplace传进来的值为true不进入下面的判断
if (!afterReplace) {
PathReplaceService pService = ARouter.getInstance().navigation(PathReplaceService.class);
if (null != pService) {
path = pService.forString(path);
}
}
//返回对象
return new Postcard(path, group);
}
}
Postcard.java
这里调用构造函数最后将path和group进行了赋值，mBundle赋值为new Bundle();
public Postcard(String path, String group) {
this(path, group, null, null);
}
public Postcard(String path, String group, Uri uri, Bundle bundle) {
setPath(path);
setGroup(group);
setUri(uri);
this.mBundle = (null == bundle ? new Bundle() : bundle);
}
build方法执行完后接着看navigation方法：
Postcard.java
public Object navigation() {
return navigation(null);
}
/**
* Navigation to the route with path in postcard.
*
* @param context Activity and so on.
*/
public Object navigation(Context context) {
return navigation(context, null);
}
/**
* Navigation to the route with path in postcard.
*
* @param context Activity and so on.
*/
public Object navigation(Context context, NavigationCallback callback) {
return ARouter.getInstance().navigation(context, this, -1, callback);
}
调用到最后又调到了Arouter的navigation方法
ARouter.java
public Object navigation(Context mContext, Postcard postcard, int requestCode, NavigationCallback callback) {
return _ARouter.getInstance().navigation(mContext, postcard, requestCode, callback);
}
_ARouter.java
protected Object navigation(final Context context, final Postcard postcard, final int requestCode, final NavigationCallback callback) {
//自定义的预处理服务
PretreatmentService pretreatmentService = ARouter.getInstance().navigation(PretreatmentService.class);
if (null != pretreatmentService && !pretreatmentService.onPretreatment(context, postcard)) {
// Pretreatment failed, navigation canceled.
return null;
}
// Set context to postcard.
postcard.setContext(null == context ? mContext : context);
try {
//通过这个方法完善postcard的信息
LogisticsCenter.completion(postcard);
} catch (NoRouteFoundException ex) {
logger.warning(Consts.TAG, ex.getMessage());
if (debuggable()) {
// Show friendly tips for user.
runInMainThread(new Runnable() {
@Override
public void run() {
Toast.makeText(mContext, "There's no route matched!\n" +
" Path = [" + postcard.getPath() + "]\n" +
" Group = [" + postcard.getGroup() + "]", Toast.LENGTH_LONG).show();
}
});
}
if (null != callback) {
callback.onLost(postcard);
} 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;
}
//callback不为null则回调onFound
if (null != callback) {
callback.onFound(postcard);
}
//执行拦截器
if (!postcard.isGreenChannel()) { // It must be run in async thread, maybe interceptor cost too mush time made ANR.
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;
}
看下completion的方法实现
public synchronized static void completion(Postcard postcard) {
if (null == postcard) {
throw new NoRouteFoundException(TAG + "No postcard!");
}
//static Map<String, RouteMeta> routes = new HashMap<>();
//第一次加载Warehouse.routes是空的所以进入下面的判断
RouteMeta routeMeta = Warehouse.routes.get(postcard.getPath());
if (null == routeMeta) {
// Maybe its does't exist, or didn't load.
//static Map<String, Class<? extends IRouteGroup>> groupsIndex = new HashMap<>();
//初始化时每个模块都会将group信息加载到groupIndex中
//判断是否有这个路由组，如果不包含则抛出异常
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()));
}
//包含这个路由组，则加载当前路由组的所有数据到内存中
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() + "]");
}
//重新加载，routeMeta 不为null 走else判断
completion(postcard); // Reload
}
} else {
//对postcard信息进行赋值完善
postcard.setDestination(routeMeta.getDestination());
postcard.setType(routeMeta.getType());
postcard.setPriority(routeMeta.getPriority());
postcard.setExtra(routeMeta.getExtra());
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);
if (null == instance) { // There's no instance of this provider
IProvider provider;
try {
provider = providerMeta.getConstructor().newInstance();
provider.init(mContext);
Warehouse.providers.put(providerMeta, provider);
instance = provider;
} catch (Exception e) {
logger.error(TAG, "Init provider failed!", e);
throw new HandlerException("Init provider failed!");
}
}
postcard.setProvider(instance);
postcard.greenChannel(); // Provider should skip all of interceptors
break;
case FRAGMENT:
postcard.greenChannel(); // Fragment needn't interceptors
default:
break;
}
}
}
加载当前路由组的路由信息
public synchronized static void addRouteGroupDynamic(String groupName, IRouteGroup group) throws NoSuchMethodException, IllegalAccessException, InvocationTargetException, InstantiationException {
if (Warehouse.groupsIndex.containsKey(groupName)){
// If this group is included, but it has not been loaded
// load this group first, because dynamic route has high priority.
//如果groupIndex中包含当前要跳转的路由组，则获取到对应class并创建实例，调用loadInto方法加载当前组所有的路由信息到routes中。
Warehouse.groupsIndex.get(groupName).getConstructor().newInstance().loadInto(Warehouse.routes);
//加载过的路由组从groupsIndex移除，避免重复加载
Warehouse.groupsIndex.remove(groupName);
}
// cover old group.
if (null != group) {
group.loadInto(Warehouse.routes);
}
}
拦截器中onContinue继续调用_navigation方法
private Object _navigation(final Postcard postcard, final int requestCode, final NavigationCallback callback) {
final Context currentContext = postcard.getContext();
//判断类型
switch (postcard.getType()) {
case ACTIVITY:
// Build intent
//创建Intent
final Intent intent = new Intent(currentContext, postcard.getDestination());
//设置传递数据
intent.putExtras(postcard.getExtras());
// Set flags.
//设置启动的flag
int flags = postcard.getFlags();
if (0 != flags) {
intent.setFlags(flags);
}
// Non activity, need FLAG_ACTIVITY_NEW_TASK
//如果不是从Activity启动则新创建一个栈
if (!(currentContext instanceof Activity)) {
intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
}
// Set Actions
//设置action
String action = postcard.getAction();
if (!TextUtils.isEmpty(action)) {
intent.setAction(action);
}
// Navigation in main looper.
runInMainThread(new Runnable() {
@Override
public void run() {
//启动Activity
startActivity(requestCode, currentContext, intent, postcard, callback);
}
});
break;
case PROVIDER:
return postcard.getProvider();
//BroadCast、ContentProvider、Fragment都是反射创建实例
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;
}
梳理下上面的流程：
- 调用build方法构建Postcard对象
- 调用navigation方法通过获取组路由信息加载本组全部路由信息并完善Postcard对象
- 执行所有的拦截器
- 创建Intent调用StartActivity进行跳转
从上面的流程也可以看出来，路由信息并不是在初始化时就全部加载到内存中的，只有当我们用到某一组路由中的一个path时才会加载整组的路由信息，这样就做到了按需加载减少内存的占用。
五、服务和拦截器
实现IProvider接口的实现类称作服务，实现IIntercepter接口的实现类称作拦截器。下面我们看下Provider和Intercepter的实现。
还是看LogisticsCenter中的init方法中for循环中的处理。
LogisticsCenter.java
/**
* LogisticsCenter init, load all metas in memory. Demand initialization
*/
public synchronized static void init(Context context, ThreadPoolExecutor tpe) throws HandlerException {
mContext = context;
executor = tpe;
try {
long startInit = System.currentTimeMillis();
//如果我们使用了Arouter的gradle插件那么这个方法会使用ASM插桩自动补全代码
//load by plugin first
loadRouterMap();
if (registerByPlugin) {
//如果通过插件加载过了就打印日志
logger.info(TAG, "Load router map by arouter-auto-register plugin.");
} else {//如果没使用插件加载则执行下面的代码
Set<String> routerMap;
//每次可调试时或者版本号新增后，它都会重建路由映射
// It will rebuild router map every times when debuggable.
if (ARouter.debuggable() || PackageUtils.isNewVersion(context)) {
logger.info(TAG, "Run with debug mode or new install, rebuild router map.");
// These class was generated by arouter-compiler.
//加载根据注解生成的类，并保存到routerMap中
routerMap = ClassUtils.getFileNameByPackageName(mContext, ROUTE_ROOT_PAKCAGE);
// 如果map不是空的则更新SharedPreferences中的值
if (!routerMap.isEmpty()) {
context.getSharedPreferences(AROUTER_SP_CACHE_KEY, Context.MODE_PRIVATE).edit().putStringSet(AROUTER_SP_KEY_MAP, routerMap).apply();
}
//更新完成后则更新应用版本号
PackageUtils.updateVersion(context); // Save new version name when router map update finishes.
} else {
logger.info(TAG, "Load router map from cache.");
//不是调试模式或版本号新增则直接从SharedPreferences中加载
routerMap = new HashSet<>(context.getSharedPreferences(AROUTER_SP_CACHE_KEY, Context.MODE_PRIVATE).getStringSet(AROUTER_SP_KEY_MAP, new HashSet<String>()));
}
logger.info(TAG, "Find router map finished, map size = " + routerMap.size() + ", cost " + (System.currentTimeMillis() - startInit) + " ms.");
startInit = System.currentTimeMillis();
//遍历map获取className，根据类型调用IRouteRoot、IInterceptorGroup、IProviderGroup的loadInto方法填充Warehouse中的map集合
for (String className : routerMap) {
if (className.startsWith(ROUTE_ROOT_PAKCAGE + DOT + SDK_NAME + SEPARATOR + SUFFIX_ROOT)) {
// This one of root elements, load root.
// 加载模块中的路由组信息
((IRouteRoot) (Class.forName(className).getConstructor().newInstance())).loadInto(Warehouse.groupsIndex);
} else if (className.startsWith(ROUTE_ROOT_PAKCAGE + DOT + SDK_NAME + SEPARATOR + SUFFIX_INTERCEPTORS)) {
// Load interceptorMeta
//加载拦截器
((IInterceptorGroup) (Class.forName(className).getConstructor().newInstance())).loadInto(Warehouse.interceptorsIndex);
} else if (className.startsWith(ROUTE_ROOT_PAKCAGE + DOT + SDK_NAME + SEPARATOR + SUFFIX_PROVIDERS)) {
// Load providerIndex
//加载provider
((IProviderGroup) (Class.forName(className).getConstructor().newInstance())).loadInto(Warehouse.providersIndex);
}
}
}
logger.info(TAG, "Load root element finished, cost " + (System.currentTimeMillis() - startInit) + " ms.");
if (Warehouse.groupsIndex.size() == 0) {
logger.error(TAG, "No mapping files were found, check your configuration please!");
}
if (ARouter.debuggable()) {
logger.debug(TAG, String.format(Locale.getDefault(), "LogisticsCenter has already been loaded, GroupIndex[%d], InterceptorIndex[%d], ProviderIndex[%d]", Warehouse.groupsIndex.size(), Warehouse.interceptorsIndex.size(), Warehouse.providersIndex.size()));
}
} catch (Exception e) {
throw new HandlerException(TAG + "ARouter init logistics center exception! [" + e.getMessage() + "]");
}
}
自定义的Service
@Route(path = "/service/test")
public class TestServiceImp implements TestService{
@Override
public void test() {
}
@Override
public void init(Context context) {
}
}
provider会在编译时额外生成下面这个类
public class ARouter$$Providers$$app implements IProviderGroup {
@Override
public void loadInto(Map<String, RouteMeta> providers) {
//加载service信息到内存中
providers.put("com.example.arutortest.TestService", RouteMeta.build(RouteType.PROVIDER, TestServiceImp.class, "/service/test", "service", null, -1, -2147483648));
}
}
ARouter$$Root$$app中也会添加service路由组的信息，这个和之前的路由一样。
public class ARouter$$Root$$app implements IRouteRoot {
@Override
public void loadInto(Map<String, Class<? extends IRouteGroup>> routes) {
routes.put("app_test", ARouter$$Group$$app_test.class);
routes.put("app_test1", ARouter$$Group$$app_test1.class);
routes.put("service", ARouter$$Group$$service.class);
}
}
public class ARouter$$Group$$service implements IRouteGroup {
@Override
public void loadInto(Map<String, RouteMeta> atlas) {
atlas.put("/service/test", RouteMeta.build(RouteType.PROVIDER, TestServiceImp.class, "/service/test", "service", null, -1, -2147483648));
}
}
completion完善postcard的方法实现中对provider的处理
public synchronized static void completion(Postcard postcard) {
if (null == postcard) {
throw new NoRouteFoundException(TAG + "No postcard!");
}
//static Map<String, RouteMeta> routes = new HashMap<>();
//第一次加载Warehouse.routes是空的所以进入下面的判断
RouteMeta routeMeta = Warehouse.routes.get(postcard.getPath());
if (null == routeMeta) {
// Maybe its does't exist, or didn't load.
//static Map<String, Class<? extends IRouteGroup>> groupsIndex = new HashMap<>();
//初始化时每个模块都会将group信息加载到groupIndex中
//判断是否有这个路由组，如果不包含则抛出异常
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()));
}
//包含这个路由组，则加载当前路由组的所有数据到内存中
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() + "]");
}
//重新加载，routeMeta 不为null 走else判断
completion(postcard); // Reload
}
} else {
//对postcard信息进行赋值完善
postcard.setDestination(routeMeta.getDestination());
postcard.setType(routeMeta.getType());
postcard.setPriority(routeMeta.getPriority());
postcard.setExtra(routeMeta.getExtra());
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());
}
//对provider的处理
switch (routeMeta.getType()) {
case PROVIDER: // if the route is provider, should find its instance
// Its provider, so it must implement IProvider
//获取class对象
Class<? extends IProvider> providerMeta = (Class<? extends IProvider>) routeMeta.getDestination();
//providers中取出IProvider实例
IProvider instance = Warehouse.providers.get(providerMeta);
if (null == instance) { // There's no instance of this provider
//如果是空的则创建实例并保存到Warehouse.providers中
IProvider provider;
try {
provider = providerMeta.getConstructor().newInstance();
provider.init(mContext);
Warehouse.providers.put(providerMeta, provider);
instance = provider;
} catch (Exception e) {
logger.error(TAG, "Init provider failed!", e);
throw new HandlerException("Init provider failed!");
}
}
//postcard中保存Provider实例
postcard.setProvider(instance);
//设置绿色通道
postcard.greenChannel(); // Provider should skip all of interceptors
break;
case FRAGMENT:
postcard.greenChannel(); // Fragment needn't interceptors
default:
break;
}
}
}
_navigation方法中当类型为PROVIDER时直接返回之前创建的实例return postcard.getProvider()
private Object _navigation(final Postcard postcard, final int requestCode, final NavigationCallback callback) {
final Context currentContext = postcard.getContext();
//判断类型
switch (postcard.getType()) {
case ACTIVITY:
// Build intent
//创建Intent
final Intent intent = new Intent(currentContext, postcard.getDestination());
//设置传递数据
intent.putExtras(postcard.getExtras());
// Set flags.
//设置启动的flag
int flags = postcard.getFlags();
if (0 != flags) {
intent.setFlags(flags);
}
// Non activity, need FLAG_ACTIVITY_NEW_TASK
//如果不是从Activity启动则新创建一个栈
if (!(currentContext instanceof Activity)) {
intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
}
// Set Actions
//设置action
String action = postcard.getAction();
if (!TextUtils.isEmpty(action)) {
intent.setAction(action);
}
// Navigation in main looper.
runInMainThread(new Runnable() {
@Override
public void run() {
//启动Activity
startActivity(requestCode, currentContext, intent, postcard, callback);
}
});
break;
//直接返回实例
case PROVIDER:
return postcard.getProvider();
//BroadCast、ContentProvider、Fragment都是反射创建实例
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;
}
和RouteType.ACTIVITY不同，RouteType.PROVIDER会在完善postcard信息时创建实例保存到postcard和Warehouse.providers中。_navigation方法返回provider实例即可。
_ARouter.java中当postcard信息完善完成后则会执行拦截器
protected Object navigation(final Context context, final Postcard postcard, final int requestCode, final NavigationCallback callback) {
//自定义的预处理服务
PretreatmentService pretreatmentService = ARouter.getInstance().navigation(PretreatmentService.class);
if (null != pretreatmentService && !pretreatmentService.onPretreatment(context, postcard)) {
// Pretreatment failed, navigation canceled.
return null;
}
// Set context to postcard.
postcard.setContext(null == context ? mContext : context);
try {
//通过这个方法完善postcard的信息
LogisticsCenter.completion(postcard);
} catch (NoRouteFoundException ex) {
logger.warning(Consts.TAG, ex.getMessage());
if (debuggable()) {
// Show friendly tips for user.
runInMainThread(new Runnable() {
@Override
public void run() {
Toast.makeText(mContext, "There's no route matched!\n" +
" Path = [" + postcard.getPath() + "]\n" +
" Group = [" + postcard.getGroup() + "]", Toast.LENGTH_LONG).show();
}
});
}
if (null != callback) {
callback.onLost(postcard);
} 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;
}
//callback不为null则回调onFound
if (null != callback) {
callback.onFound(postcard);
}
//如果不是绿色通道则执行拦截器
if (!postcard.isGreenChannel()) { // It must be run in async thread, maybe interceptor cost too mush time made ANR.
//interceptorService是在init方法后的afterInit中创建的
interceptorService.doInterceptions(postcard, new InterceptorCallback() {
/**
* Continue process
*
* @param postcard route meta
*/
@Override
public void onContinue(Postcard postcard) {
//继续执行路由
_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) {
//路由中断
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;
}
处理Interceptor的service类
@Route(path = "/arouter/service/interceptor")
public class InterceptorServiceImpl implements InterceptorService {
private static boolean interceptorHasInit;
private static final Object interceptorInitLock = new Object();
@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);
}
}
/**
* Excute interceptor
*
* @param index current interceptor index
* @param counter interceptor counter
* @param postcard routeMeta
*/
private static void _execute(final int index, final CancelableCountDownLatch counter, final Postcard postcard) {
if (index < Warehouse.interceptors.size()) {
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();
_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());
// }
}
});
}
}
@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();
}
}
}
});
}
private static void checkInterceptorsInitStatus() {
synchronized (interceptorInitLock) {
while (!interceptorHasInit) {
try {
interceptorInitLock.wait(10 * 1000);
} catch (InterruptedException e) {
throw new HandlerException(TAG + "Interceptor init cost too much time error! reason = [" + e.getMessage() + "]");
}
}
}
}
}
先看下init方法
@Override
public void init(final Context context) {
LogisticsCenter.executor.execute(new Runnable() {
@Override
public void run() {
if (MapUtils.isNotEmpty(Warehouse.interceptorsIndex)) {
//遍历Warehouse.interceptorsIndex
for (Map.Entry<Integer, Class<? extends IInterceptor>> entry : Warehouse.interceptorsIndex.entrySet()) {
//获取class对象
Class<? extends IInterceptor> interceptorClass = entry.getValue();
try {
//获取实例
IInterceptor iInterceptor = interceptorClass.getConstructor().newInstance();
//调用拦截器init方法
iInterceptor.init(context);
//保存拦截器
Warehouse.interceptors.add(iInterceptor);
} catch (Exception ex) {
throw new HandlerException(TAG + "ARouter init interceptor error! name = [" + interceptorClass.getName() + "], reason = [" + ex.getMessage() + "]");
}
}
//拦截器初始化标记设置为true
interceptorHasInit = true;
logger.info(TAG, "ARouter interceptors init over.");
synchronized (interceptorInitLock) {
interceptorInitLock.notifyAll();
}
}
}
});
}
执行拦截器逻辑
@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() {
//保证所有的拦截器都执行
CancelableCountDownLatch interceptorCounter = new CancelableCountDownLatch(Warehouse.interceptors.size());
try {
_execute(0, interceptorCounter, postcard);
//设置超时时间
interceptorCounter.await(postcard.getTimeout(), TimeUnit.SECONDS);
//拦截器未执行完
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 {
//所有的拦截器执行完成
callback.onContinue(postcard);
}
} catch (Exception e) {
callback.onInterrupt(e);
}
}
});
} else {
callback.onContinue(postcard);
}
}
递归调用拦截器执行process方法，直达执行完所有的拦截器。若有拦截器进行了拦截则不执行路由跳转
/**
* Excute interceptor
*
* @param index current interceptor index
* @param counter interceptor counter
* @param postcard routeMeta
*/
private static void _execute(final int index, final CancelableCountDownLatch counter, final Postcard postcard) {
if (index < Warehouse.interceptors.size()) {
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();
_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());
// }
}
});
}
}
拦截器在框架初始化完成后创建了InterceptorServiceImpl并在init方法中加载所有的拦截器。在每次页面跳转时执行所有的拦截器逻辑。
