public interface ProcessingEnvironment {
    Map getOptions();

    Messager getMessager();

    Filer getFiler();

    Elements getElementUtils();

    Types getTypeUtils();

    SourceVersion getSourceVersion();

    Locale getLocale();
}
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    private Elements elementUtils;
    private Types types;
    
    @Override
    public synchronized void init(ProcessingEnvironment processingEnv) {
        super.init(processingEnv);
        types = processingEnv.getTypeUtils();
        elementUtils = processingEnv.getElementUtils();
    }
    
    public boolean isSubType(Element element, String className) {
        return element != null && isSubType(element.asType(), className);
    }
    
    public TypeMirror typeMirror(String className) {
        return typeElement(className).asType();
    }
    
    public TypeElement typeElement(String className) {
        return elementUtils.getTypeElement(className);
    }
    
    public boolean isSubType(TypeMirror type, String className) {
        return type != null && types.isSubtype(type, typeMirror(className));
    }
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 @Override
    public boolean process(Set annotations, RoundEnvironment roundEnv) {
        if (CollectionUtils.isNotEmpty(annotations)) {
            initRouter(moduleName, roundEnv);
            return true;
        }
        return false;
    }

    private void initRouter(String name, RoundEnvironment roundEnv) {
        Set elements = roundEnv.getElementsAnnotatedWith(BindRouter.class);
        if (elements.isEmpty()) {
            return;
        }
        //生成一个init 的final 静态方法
        MethodSpec.Builder initMethod = MethodSpec.methodBuilder("init")
                .addModifiers(Modifier.PUBLIC, Modifier.FINAL, Modifier.STATIC);
        TypeMirror type_Activity = elementUtils.getTypeElement(Const.ACTIVITY).asType();
        TypeMirror fragmentTm = elementUtils.getTypeElement(Const.FRAGMENT).asType();
        TypeMirror callBackTm = elementUtils.getTypeElement(Const.RUNNABLE).asType();
        //一、收集信息
        int count = 0;
        //遍历Element元素
        for (Element element : elements) {
            //检查element类型
            //field type
            BindRouter router = element.getAnnotation(BindRouter.class);
            ClassName className;
            if (element.getKind() == ElementKind.CLASS) {
                className = ClassName.get((TypeElement) element);
            } else if (element.getKind() == ElementKind.METHOD) {
                className = ClassName.get((TypeElement) element.getEnclosingElement());
            } else {
                throw new IllegalArgumentException("unknow type");
            }
            // 一个页面可以注册多个路由
            String[] id = router.urls();
            for (String format : id) {
                int weight = router.weight();
                TypeMirror type = element.asType();
                //判断是不是一个方法
                if (types.isSubtype(type, callBackTm)) {
                    String callbackName = "callBack" + count;
                    initMethod.addStatement(className + " " + callbackName + "=new " + className + "()");
                    CodeBlock interceptorBlock = buildInterceptors(getInterceptors(router));
                    initMethod.addStatement("com.kronos.router.Router.map($S,$L$L)", format, callbackName, interceptorBlock);
                    count++;
                    continue;
                }
                if (weight > 0) {
                    String bundleName = "bundle" + count;
                    initMethod.addStatement("android.os.Bundle " + bundleName + "=new android.os.Bundle();");
                    String optionsName = "options" + count;
                    initMethod.addStatement("com.kronos.router.model.RouterOptions " + optionsName + "=new com.kronos.router.model.RouterOptions("
                            + bundleName + ")");
                    initMethod.addStatement(optionsName + ".setWeight(" + weight + ")");
                    CodeBlock interceptorBlock = buildInterceptors(getInterceptors(router));
                    initMethod.addStatement("com.kronos.router.Router.map($S,$T.class," + optionsName + "$L)",
                            format, className, interceptorBlock);
                } else {
                    CodeBlock interceptorBlock = buildInterceptors(getInterceptors(router));
                    initMethod.addStatement("com.kronos.router.Router.map($S,$T.class,$L)", format, className, interceptorBlock);
                }
            }
            count++;
        }
        //将方法插入到一个特定包名的类名下
        String moduleName = "RouterInit_" + name;
        TypeSpec routerMapping = TypeSpec.classBuilder(moduleName)
                .addModifiers(Modifier.PUBLIC, Modifier.FINAL)
                .addMethod(initMethod.build())
                .build();
        try {
            //生成java文件
            JavaFile.builder("com.kronos.router.init", routerMapping)
                    .build()
                    .writeTo(filer);
        } catch (IOException ignored) {

        }
    }
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apply plugin: 'java-library'
apply plugin: 'kotlin'
apply plugin: 'kotlin-kapt'

dependencies {
    implementation 'com.google.auto.service:auto-service:1.0-rc5'
    implementation 'com.squareup:javapoet:1.10.0'
    implementation 'com.github.leifzhang:RouterAnnotation:0.5.0'
    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"
    kapt "com.google.auto.service:auto-service:1.0-rc5"
}
sourceCompatibility = 1.8
targetCompatibility = 1.8