WMRouter采用APT来对注解进行处理并生成相应模版代码，下面看一下通过Path实现Fragment跳转的注解处理过程。首先对目标Fragment添加注解：
@RouterPage(path = ["/fragment/paging/test"]) class PagingTestFragment()生成的模版代码为：
//位置：com.sankuai.waimai.router.generated/ public class PageAnnotationInit_7e09d0c7c2c720bbbacddb0cedbfec26 implements IPageAnnotationInit { public void init(PageAnnotationHandler handler) { handler.register("/fragment/paging/test", new FragmentTransactionHandler("com.yy.oms.logistics.home.fragment.PagingTestFragment")); } } //位置：com.sankuai.waimai.router.generated.service/ public class ServiceInit_ac827e6cbb5a2489f812c8baa8e9ff42 { public static void init() { ServiceLoader.put(IPageAnnotationInit.class, "com.sankuai.waimai.router.generated.PageAnnotationInit_7e09d0c7c2c720bbbacddb0cedbfec26", com.sankuai.waimai.router.generated.PageAnnotationInit_7e09d0c7c2c720bbbacddb0cedbfec26.class, false); } }对于自动生成代码的处理往往是通过Gradle插件来完成的。
在业务中定义一个Plugin来注册一个Transform：
class XxxPlugin : Plugin<Project> { override fun apply(p0: Project) { val android = p0.extensions.getByType(AppExtension::class.java) p0.extensions.create( XxxPluginExtension.getExtensionName(), XxxPluginExtension::class.java ) android.registerTransform(XxxTransform(p0, null)) } }这里的XxxTransform类是用来处理通过SPI定义的类的，看一下其主要方法：
class XxxTransform(val project: Project, var extension: XxxPluginExtension?) : Transform() { //spi加载注册的类 val transforms = ServiceLoaderUtils.loadClassTransforms(project) override fun transform(invocation: TransformInvocation) { //编译前 val transformInvocation = XxxTransformInvocation(invocation, this) transforms.forEach { it.beforeTransform(transformInvocation.XxxContext, project) } //编译开始 if (transformInvocation.isIncremental) { transformIncremental(transformInvocation) } else { invocation.outputProvider.deleteAll() transformFull(transformInvocation) } //编译后 transformInvocation.onPostTransform() transforms.forEach { it.afterTransform(transformInvocation.XxxContext) } } //增量编译 private fun transformIncremental(invocation: XxxTransformInvocation) { invocation.inputs.parallelStream().forEach { TransformJarUtils.transformJarInputs(it.jarInputs, invocation) TransformClassUtils.transformClassFile(invocation, it.directoryInputs) } } //全量编译 private fun transformFull(invocation: XxxTransformInvocation) { invocation.inputs.parallelStream().forEach { TransformJarUtils.transformJarInputsFull(it.jarInputs, invocation) TransformClassUtils.transformClassFileFull(invocation, it.directoryInputs) } } }这里先调用loadClassTransforms()方法加载通过SPI注册的类，其定义在ServiceLoaderUtils静态类中：
//ServiceLoaderUtils.java fun loadClassTransforms(project: Project): ArrayList<IClassTransform> { val list = ArrayList<IClassTransform>() ServiceLoader.load(IClassTransform::class.java).iterator().forEach { it.getTransformExtension()?.let { project.extensions.create(it.getExtensionName(), it.javaClass) } list.add(it) } list.sortBy { -it.priority() } return list }这里调用ServiceLoader来将META-INFO/services/下配置文件中的类实例化。
这里定义的接口为IClassTransform.kt，定义一个实现类WMRouterTransform.kt，并用AutoService注解：
@AutoService(IClassTransform::class) class WMRouterTransform : IClassTransform {}AutoService是Google提供的用于生成SPI配置文件的，可以参考Google AutoService。编译后会在同一根目录的build/libs/module名.jar/META-INFO/services/目录下生成配置文件：com.xx.xx.IClassTransform，其文件内容为：
com.yy.oms.plugin.transforms.router.WMRouterTransform下面看一下WMRouterTransform是如何初始化Service的。
在业务中，会使用ASM对生成的代码进行收集并存储在内存中，然后可以对缓存的信息进行查找，该过程在WMRouterTransform类中完成：
//WMRouterTransform.kt private var targetClasses: MutableSet<String> = Collections.newSetFromMap(ConcurrentHashMap()) private const val GEN_PKG_SERVICE = "$GEN_PKG/service" //查找GEN_PKG_SERVICE路径下的文件并放在targetClasses中 override fun beforeTransform(context: TransformContext, project: Project) { val cost = measureTimeMillis { context.getClassNodeCache() .findClassNodeCache { it.name?.startsWith(GEN_PKG_SERVICE) ?: false } ?.forEach { targetClasses.add(it.name!!) } } } override fun afterTransform(context: TransformContext) { execute(context) super.afterTransform(context) } private fun execute(context: TransformContext) { if (targetClasses.isEmpty()) return val className: String = SERVICE_LOADER_INIT val cost = measureTimeMillis { try { // write val writer = ClassWriter(ClassWriter.COMPUTE_FRAMES or ClassWriter.COMPUTE_MAXS) val cv: ClassVisitor = object : ClassVisitor(Opcodes.ASM5, writer) {} cv.visit(50, Opcodes.ACC_PUBLIC, className, null, "java/lang/Object", null) val mv = cv.visitMethod(Opcodes.ACC_PUBLIC or Opcodes.ACC_STATIC, INIT_METHOD, "()V", null, null) mv.visitCode() //插入代码：调用service的init()方法 for (clazz in targetClasses) { mv.visitMethodInsn(Opcodes.INVOKESTATIC, clazz, "init", "()V", false) } mv.visitMaxs(0, 0) mv.visitInsn(Opcodes.RETURN) mv.visitEnd() cv.visitEnd() // output file val dest = File(context.getOutPutDirPath(), className + SdkConstants.DOT_CLASS).touch() writer.toByteArray().redirect(dest) getLogger().i("$TAG execute generated file $dest, length ${dest.length()}") } catch (e: Exception) { getLogger().i("$TAG execute error: $e") } } getLogger().i("$TAG execute cost ${cost}ms, generated class $className") }这里调用visitMethodInsn()方法实际调用的是ServiceInit_ac827e6cbb5a2489f812c8baa8e9ff42类的init()方法，在init()方法中会调用ServiceLoader的put()方法：
public static void put(Class interfaceClass, String key, Class implementClass, boolean singleton) { ServiceLoader loader = SERVICES.get(interfaceClass); if (loader == null) { loader = new ServiceLoader(interfaceClass); SERVICES.put(interfaceClass, loader); } loader.putImpl(key, implementClass, singleton); }这里的implementClass即是PageAnnotationInit_7e09d0c7c2c720bbbacddb0cedbfec26类的Class，进一步将implementClass为参数调用putImpl()方法：
private void putImpl(String key, Class implementClass, boolean singleton) { if (key != null && implementClass != null) { mMap.put(key, new ServiceImpl(key, implementClass, singleton)); } }将implementClass包装成一个ServiceImpl对象并存放在mMap 中。
Annotation初始化的调用链路为：
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.edge-pattern-dashed{stroke-dasharray:3}#mermaid-svg-Peauh0FL01XGU1q4 .edge-pattern-dotted{stroke-dasharray:2}#mermaid-svg-Peauh0FL01XGU1q4 .marker{fill:#333}#mermaid-svg-Peauh0FL01XGU1q4 .marker.cross{stroke:#333} :root { --mermaid-font-family: "trebuchet ms", verdana, arial;} #mermaid-svg-Peauh0FL01XGU1q4 { color: rgba(0, 0, 0, 0.75); font: ; } XxApplication Router DefaultRootUriHandler PageAnnotationHandler LazyInitHelper RouterComponents DefaultAnnotationLoader init() lazyInit() lazyInit() lazyInit() performInit() initAnnotationConfig() loadAnnotation() load() XxApplication Router DefaultRootUriHandler PageAnnotationHandler LazyInitHelper RouterComponents DefaultAnnotationLoader从调用链可以看到最终会调用DefaultAnnotationLoader的load()方法：
@Override public <T extends UriHandler> void load(T handler, Class<? extends AnnotationInit<T>> initClass) { List<? extends AnnotationInit<T>> services = Router.getAllServices(initClass); for (AnnotationInit<T> service : services) { service.init(handler); } }这里就会拿到Service初始化时记录在mMap中所有的ServiceImpl对象，然后执行其init()方法，这里就会执行PageAnnotationInit_7e09d0c7c2c720bbbacddb0cedbfec26类的init()方法，看一下“APT注解处理”一节的代码可知会调用PathHandler类的register()方法：
/** * 注册一个子节点 * * @param path path * @param target 支持ActivityClassName、ActivityClass、UriHandler * @param exported 是否允许外部跳转 * @param interceptors 要添加的interceptor */ public void register(String path, Object target, boolean exported, UriInterceptor... interceptors) { if (!TextUtils.isEmpty(path)) { path = RouterUtils.appendSlash(path); UriHandler parse = UriTargetTools.parse(target, exported, interceptors); UriHandler prev = mMap.put(path, parse); if (prev != null) { Debugger.fatal("[%s] 重复注册path='%s'的UriHandler: %s, %s", this, path, prev, parse); } } }这里的target是一个FragmentTransactionHandler对象，将该对象转化成类型为UriHandler的parse对象并保存在一个Map中。
显示一个Fragment必须先实例化该Fragment对象，通过一下代码实现：
FragmentBuildUriRequest(requireContext(), "/fragment/paging/test".pageUri) .getFragment() suspend fun AbsFragmentUriRequest.getFragment() = suspendCancellableCoroutine<Fragment?> { onComplete(object : OnCompleteListener { override fun onSuccess(request: UriRequest) { val fragment = request.getField(Fragment::class.java, FragmentBuildUriRequest.FRAGMENT) it.resume(fragment) } override fun onError(request: UriRequest, resultCode: Int) { it.resume(null) } }).start() }onComplete()方法添加了一个监听对象，最终会调用FragmentBuildUriRequest的父类UriRequest的start()方法，其调用链如图：
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text{fill:#9370db;stroke:none;font-size:10px;font-family:'trebuchet ms', verdana, arial;font-family:var(--mermaid-font-family)}#mermaid-svg-8XpwHNmsSZeN162P g.stateGroup text{fill:#9370db;fill:#333;stroke:none;font-size:10px}#mermaid-svg-8XpwHNmsSZeN162P g.statediagram-cluster .cluster-label text{fill:#333}#mermaid-svg-8XpwHNmsSZeN162P g.stateGroup .state-title{font-weight:bolder;fill:#000}#mermaid-svg-8XpwHNmsSZeN162P g.stateGroup rect{fill:#ECECFF;stroke:#9370db}#mermaid-svg-8XpwHNmsSZeN162P g.stateGroup line{stroke:#9370db;stroke-width:1}#mermaid-svg-8XpwHNmsSZeN162P .transition{stroke:#9370db;stroke-width:1;fill:none}#mermaid-svg-8XpwHNmsSZeN162P .stateGroup .composit{fill:white;border-bottom:1px}#mermaid-svg-8XpwHNmsSZeN162P .stateGroup .alt-composit{fill:#e0e0e0;border-bottom:1px}#mermaid-svg-8XpwHNmsSZeN162P .state-note{stroke:#aa3;fill:#fff5ad}#mermaid-svg-8XpwHNmsSZeN162P .state-note text{fill:black;stroke:none;font-size:10px}#mermaid-svg-8XpwHNmsSZeN162P .stateLabel 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.statediagram-cluster.statediagram-cluster-alt .inner{fill:#e0e0e0}#mermaid-svg-8XpwHNmsSZeN162P .statediagram-cluster .inner{rx:0;ry:0}#mermaid-svg-8XpwHNmsSZeN162P .statediagram-state rect.basic{rx:5px;ry:5px}#mermaid-svg-8XpwHNmsSZeN162P .statediagram-state rect.divider{stroke-dasharray:10,10;fill:#efefef}#mermaid-svg-8XpwHNmsSZeN162P .note-edge{stroke-dasharray:5}#mermaid-svg-8XpwHNmsSZeN162P .statediagram-note rect{fill:#fff5ad;stroke:#aa3;stroke-width:1px;rx:0;ry:0}:root{--mermaid-font-family: '"trebuchet ms", verdana, arial';--mermaid-font-family: "Comic Sans MS", "Comic Sans", cursive}#mermaid-svg-8XpwHNmsSZeN162P .error-icon{fill:#522}#mermaid-svg-8XpwHNmsSZeN162P .error-text{fill:#522;stroke:#522}#mermaid-svg-8XpwHNmsSZeN162P .edge-thickness-normal{stroke-width:2px}#mermaid-svg-8XpwHNmsSZeN162P .edge-thickness-thick{stroke-width:3.5px}#mermaid-svg-8XpwHNmsSZeN162P .edge-pattern-solid{stroke-dasharray:0}#mermaid-svg-8XpwHNmsSZeN162P .edge-pattern-dashed{stroke-dasharray:3}#mermaid-svg-8XpwHNmsSZeN162P .edge-pattern-dotted{stroke-dasharray:2}#mermaid-svg-8XpwHNmsSZeN162P .marker{fill:#333}#mermaid-svg-8XpwHNmsSZeN162P .marker.cross{stroke:#333} :root { --mermaid-font-family: "trebuchet ms", verdana, arial;} #mermaid-svg-8XpwHNmsSZeN162P { color: rgba(0, 0, 0, 0.75); font: ; } UriRequest Router RootUriHandler UriHandler PageAnnotationHandler FragmentTransactionHandler startUri() startUri() handle() handleInternal() handleInternal() UriRequest Router RootUriHandler UriHandler PageAnnotationHandler FragmentTransactionHandler在分析后面逻辑之前需要明白Handler链的结构：DefaultRootUriHandler下有三个次级Handler（如：PageAnnotationHandler、UriAnnotationHandler、RegexAnnotationHandler），各个次级Handler下又有子Handler（如：FragmentTransactionHandler）。看一下DefaultRootUriHandler注册次级Handle的代码：
public DefaultRootUriHandler(Context context, @Nullable String defaultScheme, @Nullable String defaultHost) { super(context); mPageAnnotationHandler = createPageAnnotationHandler(); mUriAnnotationHandler = createUriAnnotationHandler(defaultScheme, defaultHost); mRegexAnnotationHandler = createRegexAnnotationHandler(); // 处理RouterPage注解定义的内部页面跳转，如果注解没定义，直接结束分发 addChildHandler(mPageAnnotationHandler, 300); // 处理RouterUri注解定义的URI跳转，如果注解没定义，继续分发到后面的Handler addChildHandler(mUriAnnotationHandler, 200); // 处理RouterRegex注解定义的正则匹配 addChildHandler(mRegexAnnotationHandler, 100); // 添加其他用户自定义Handler... // 都没有处理，则尝试使用默认的StartUriHandler直接启动Uri addChildHandler(new StartUriHandler(), -100); // 全局OnCompleteListener，用于输出跳转失败提示信息 setGlobalOnCompleteListener(DefaultOnCompleteListener.INSTANCE); }因此上图的调用链中会先执行PageAnnotationHandler类的handleInternal()方法：
//PageAnnotationHandler.java @Override protected void handleInternal(@NonNull final UriRequest request, @NonNull final UriCallback callback) { UriHandler h = getChild(request); if (h != null) { h.handle(request, new UriCallback() { @Override public void onNext() { handleByDefault(request, callback); } @Override public void onComplete(int resultCode) { callback.onComplete(resultCode); } }); } else { handleByDefault(request, callback); } } //PathHandler.java private UriHandler getChild(@NonNull UriRequest request) { String path = request.getUri().getPath(); if (TextUtils.isEmpty(path)) { return null; } path = RouterUtils.appendSlash(path); if (TextUtils.isEmpty(mPathPrefix)) { return mMap.get(path); } if (path.startsWith(mPathPrefix)) { return mMap.get(path.substring(mPathPrefix.length())); } return null; }这里getChild()方法从mMap中取出的即是前面往其中添加的FragmentTransactionHandler对象，因此又会执行其handleInternal()方法：
@Override protected void handleInternal(@NonNull UriRequest request, @NonNull UriCallback callback) { StartFragmentAction action = request.getField(StartFragmentAction.class, StartFragmentAction.START_FRAGMENT_ACTION); if (action == null) { Debugger.fatal("FragmentTransactionHandler.handleInternal()应返回的带有StartFragmentAction"); callback.onComplete(UriResult.CODE_BAD_REQUEST); return; } if (!request.hasField(FRAGMENT_CLASS_NAME)) { //判断一下，便于被替换 request.putField(FRAGMENT_CLASS_NAME, mClassName); } // Extra Bundle extra = request.getField(Bundle.class, FIELD_INTENT_EXTRA); //*关键代码，反射构造目标Fragment对象* boolean success = action.startFragment(request, extra); // 完成 callback.onComplete(success ? UriResult.CODE_SUCCESS : UriResult.CODE_BAD_REQUEST); }先从request中获取一个StartFragmentAction对象，然后调用其startFragment()方法初始化目标Fragment并执行Fragment事务：
@Override public boolean startFragment(@NonNull UriRequest request, @NonNull Bundle bundle) throws ActivityNotFoundException, SecurityException { String fragmentClassName = request.getStringField(FragmentTransactionHandler.FRAGMENT_CLASS_NAME); if (TextUtils.isEmpty(fragmentClassName)) { Debugger.fatal("FragmentTransactionHandler.handleInternal()应返回的带有ClassName"); return false; } if (mContainerViewId == 0) { Debugger.fatal("FragmentTransactionHandler.handleInternal()mContainerViewId"); return false; } try { Fragment fragment = Fragment.instantiate(request.getContext(), fragmentClassName, bundle); if (fragment == null) { Debugger.e("FragmentTransactionUriRequest fragment init error"); return false; } Debugger.i("FragmentTransactionUriRequest fragment: ", fragment); FragmentTransaction transaction = mFragmentManager.beginTransaction(); switch (mStartType) { case TYPE_ADD: transaction.add(mContainerViewId, fragment, mTag); break; case TYPE_REPLACE: transaction.replace(mContainerViewId, fragment, mTag); break; default: Debugger.e("BuildStartFragmentAction:" + mStartType); } if (mAllowingStateLoss) { transaction.commitAllowingStateLoss(); } else { transaction.commit(); } return true; } catch (Exception e) { } } }这里的代码很熟悉了，我们看一个关键点：反射构造目标Fragment实例。
//Fragment.java public static Fragment instantiate(@NonNull Context context, @NonNull String fname, @Nullable Bundle args) { try { Class<? extends Fragment> clazz = FragmentFactory.loadFragmentClass( context.getClassLoader(), fname); //通过构造器构造目标Fragment Fragment f = clazz.getConstructor().newInstance(); if (args != null) { args.setClassLoader(f.getClass().getClassLoader()); f.setArguments(args); } return f; } catch (java.lang.InstantiationException e) {} } //Class.java public Constructor<T> getConstructor(Class<?>... parameterTypes) throws NoSuchMethodException, SecurityException { return getConstructor0(parameterTypes, Member.PUBLIC); }可以看到通过目标Fragment的无参构造器来初始化目标Fragment的，因此在文章开头提到对于含有参数的目标Fragment来说，WMRouter是不能成功构造出该Fragment实例并完成Fragment显示功能的。
先看一下使用姿势，先在一个Fragment中定义用@Autowired注解一个参数，该参数名也是argument中的key，如下：
@RouterPage(path = ["/fragment/test/router"]) class TestRouterFragment : Fragment() { @JvmField @Autowired var value1: Boolean? = false @JvmField @Autowired var value2: Byte? = 1 @JvmField @Autowired var value3: Short? = 1 }然后通过APT会生成一个TestRouterFragment$$WMRouter$$Autowired类，该类中只有一个inject()方法，该方法的作用是获取intent/argument中的数据：
public class TestRouterFragment$$WMRouter$$Autowired implements ISyringe { @Override public void inject(Object target) { TestRouterFragment substitute = (TestRouterFragment)target; substitute.value1 = substitute.getArguments().getBoolean("value1", substitute.value1); substitute.value2 = substitute.getArguments().getByte("value2", substitute.value2); substitute.value3 = substitute.getArguments().getShort("value3", substitute.value3); } }下面看一下如何通过APT来生成上面的类，源码在WMRouter库AutowiredProcessor类中：
@AutoService(Processor.class) @SupportedSourceVersion(SourceVersion.RELEASE_7) public class AutowiredProcessor extends BaseProcessor { @Override public boolean process(Set<? extends TypeElement> set, RoundEnvironment roundEnvironment) { if (set != null && !set.isEmpty()) { try { categories(roundEnvironment.getElementsAnnotatedWith(Autowired.class)); generateHelper(); } catch (Exception error) { } return true; } return false; } private void generateHelper() throws IOException, IllegalAccessException { TypeElement typeISyringe = elements.getTypeElement(ISYRINGE); TypeMirror activityTm = elements.getTypeElement(ACTIVITY_CLASS).asType(); TypeMirror fragmentTm = elements.getTypeElement(FRAGMENT_CLASS).asType(); TypeMirror fragmentTmV4 = elements.getTypeElement(FRAGMENT_V4_CLASS).asType(); // Build input param name. ParameterSpec objectParamSpec = ParameterSpec.builder(TypeName.OBJECT, "target").build(); if (parentAndChild != null && !parentAndChild.isEmpty()) { for (Map.Entry<TypeElement, List<Element>> entry : parentAndChild.entrySet()) { // Build method : 'inject' MethodSpec.Builder injectMethodBuilder = MethodSpec.methodBuilder(METHOD_INJECT) .addAnnotation(Override.class) .addModifiers(PUBLIC) .addParameter(objectParamSpec); TypeElement parent = entry.getKey(); List<Element> childs = entry.getValue(); String qualifiedName = parent.getQualifiedName().toString(); String packageName = qualifiedName.substring(0, qualifiedName.lastIndexOf(".")); //生成的类名，NAME_OF_AUTOWIRED = $$ + WMRouter + $$ + "Autowired"; String fileName = parent.getSimpleName() + NAME_OF_AUTOWIRED; // todo 改成static void TypeSpec.Builder helper = TypeSpec.classBuilder(fileName) .addJavadoc(WARNING_TIPS) .addJavadoc("\n") .addJavadoc(WARNING_TIPS2) .addSuperinterface(ClassName.get(typeISyringe)) .addModifiers(PUBLIC); injectMethodBuilder .addStatement("$T substitute = ($T)target", ClassName.get(parent), ClassName.get(parent)); // Generate method body, start inject. //有多少个注解就有多少个element for (Element element : childs) { Autowired fieldConfig = element.getAnnotation(Autowired.class); String fieldName = element.getSimpleName().toString(); String originalValue = "substitute." + fieldName; String statement = "substitute." + fieldName + " = " + buildCastCode(element, fieldConfig.typeKind()) + "substitute."; boolean isActivity = false; if (types.isSubtype(parent.asType(), activityTm)) { // Activity, then use getIntent() isActivity = true; statement += "getIntent()."; } else if (types.isSubtype(parent.asType(), fragmentTm) || types.isSubtype(parent.asType(), fragmentTmV4)) { // Fragment, then use getArguments() statement += "getArguments()."; } else { throw new IllegalAccessException("The field [" + fieldName + "] need autowired from intent, its parent must be activity or fragment!"); } statement = buildStatement(originalValue, statement, typeUtils.typeExchange(element, fieldConfig.typeKind()), isActivity); injectMethodBuilder.addStatement(statement, fieldConfig.name().isEmpty() ? fieldName : fieldConfig.name()); // Validator if (fieldConfig.required() && !element.asType().getKind() .isPrimitive()) { // Primitive wont be check. injectMethodBuilder .beginControlFlow("if (null == substitute." + fieldName + ")"); injectMethodBuilder.addStatement( "$T.e(\"" + TAG + "\", \"The field '" + fieldName + "' is null, in class '\" + $T.class.getName() + \"!\")", AndroidLog, ClassName.get(parent)); injectMethodBuilder.endControlFlow(); } } helper.addMethod(injectMethodBuilder.build()); // Generate autowire helper JavaFile.builder(packageName, helper.build()).build().writeTo(filer); } } } }这里又是使用AutoService来处理SPI类的，会在MATR-INF/services/下生成名为javax.annotation.processing.Processor的配置文件，文件内容有：com.sankuai.waimai.router.compiler.AutowiredProcessor。以上APT代码即会生成TestRouterFragment W M R o u t e r WMRouter WMRouterAutowired类，下面需要在Activity/Fragment的onCreate()方法中调用该类的inject()方法。这里可以使用和WMRouterTransform相类似的处理办法：
@AutoService(IClassTransform::class) class AutowiredTransform : IClassTransform { override fun transform(context: TransformContext, classNode: ClassNode): ClassNode { if (isTargetClassNode(classNode)) { val injector = "${classNode.name}$AUTO_WIRED_CLASS_SUFFIX" classNode.methods.find { it.name == "onCreate" && it.desc == "(Landroid/os/Bundle;)V" }?.let { // 下面的 ASM 代码对应的 java代码：(插件生成) // (new TestActivity$$WMRouter$$Autowired()).inject(this); val mv = MethodNode() mv.visitTypeInsn(Opcodes.NEW, injector) mv.visitInsn(Opcodes.DUP) mv.visitMethodInsn(Opcodes.INVOKESPECIAL, injector, "<init>", "()V", false) mv.visitVarInsn(Opcodes.ALOAD, 0) mv.visitMethodInsn(Opcodes.INVOKEVIRTUAL, injector, "inject", "(Ljava/lang/Object;)V", false) it.instructions.insert(mv.instructions) return classNode } getLogger().i("$TAG transform ${classNode.name} find OnCreate failed, create onCreate and inject $injector") // 下面的 ASM 代码对应的 java代码：（插件生成） // public void onCreate(Bundle bundle) { // (new TestActivity$$WMRouter$$Autowired()).inject(this); // super.onCreate(bundle); // } val mv: MethodVisitor = classNode.visitMethod(Opcodes.ACC_PUBLIC, "onCreate", "(Landroid/os/Bundle;)V", null, null) mv.visitCode() mv.visitTypeInsn(Opcodes.NEW, injector) mv.visitInsn(Opcodes.DUP) mv.visitMethodInsn(Opcodes.INVOKESPECIAL, injector, "<init>", "()V", false) mv.visitVarInsn(Opcodes.ALOAD, 0) mv.visitMethodInsn(Opcodes.INVOKEVIRTUAL, injector, "inject", "(Ljava/lang/Object;)V", false) mv.visitVarInsn(Opcodes.ALOAD, 0) mv.visitVarInsn(Opcodes.ALOAD, 1) mv.visitMethodInsn(Opcodes.INVOKESPECIAL, classNode.superName, "onCreate", "(Landroid/os/Bundle;)V", false) mv.visitInsn(Opcodes.RETURN) mv.visitMaxs(2, 2) mv.visitEnd() classNode.visitEnd() return classNode } return classNode } }