java - 自定义 java gradle 插件中的反射

Question

我有一个包含多个模块的 gradle 项目，每个模块都构建到它自己的 .jar 文件中。我想在自定义 java gradle 插件中使用反射，以生成关于带注释的类/方法的报告。
/build.gradle

apply plugin: com.my.plugins.MyPlugin

/buildSrc/build.gradle

repositories {
    mavenCentral()
}

dependencies {
    compile 'org.reflections:reflections:0.9.11'
    compile 'javax.annotation:javax.annotation-api:1.3.2'
}

/buildSrc/src/main/java/com/my/plugins/MyPlugin.java

@NonNullApi
public class MyPlugin implements Plugin<Project> {
    @Override
    public void apply(Project project) {
        MyTask myTask = project.getTasks().create("mytask", MyTask.class);
        Task javaCompileTask = project.getTasks().getByName("compileJava");
        myTask.dependsOn(javaCompileTask);
    }
}

/buildSrc/src/main/java/com/my/plugins/MyTask.java

public class MyTask extends DefaultTask {

    @TaskAction
    public void perform() throws MalformedURLException, ClassNotFoundException {

        List<URL> listOfURL = new ArrayList<>();
        Set<File> runtimeFiles = getProject().getConfigurations().findByName("runtime").getFiles();
        for (File file : runtimeFiles) {
            // TODO: Exclude files from gradle cache folder
            if (file.getPath().contains("build\\libs")) {
                listOfURL.add(file.toURI().toURL());
            }
        }

        URL[] urls = listOfURL.toArray(new URL[0]);
        System.out.println("\nURLs:");
        for (URL u : urls) {
            System.out.println("  " + u.toString());
        }

        ClassLoader classLoader = new URLClassLoader(urls, null);
        classLoader.loadClass("com.my.services.sample.MyClass");
        System.out.println("\nClassLoader OK!\n");

        Configuration config = new ConfigurationBuilder()
            .setUrls(ClasspathHelper.forClassLoader(classLoader))
            .filterInputsBy(new FilterBuilder().include(FilterBuilder.prefix("com.my.services")))
            .addClassLoader(classLoader)
            .setScanners(new SubTypesScanner(),
                    new TypeAnnotationsScanner(),
                    new MethodAnnotationsScanner());

        Reflections reflections = new Reflections(config);

        System.out.println("\nPermitAll Classes\n");
        for (Class c : reflections.getTypesAnnotatedWith(PermitAll.class)) {
            System.out.println(c.getName());
        }

        System.out.println("\nPermitAll Methods\n");
        for (Method m : reflections.getMethodsAnnotatedWith(PermitAll.class)) {
            System.out.println(m.getName());
        }

    }
}

当我运行 毕业我的任务 ，我在 URL 列表中的 build\libs 下看到了所有 .jar 文件的列表。
尽管 classLoader 可以成功加载(例如)MyClass，但新的 Reflections() 行会生成许多“无法获取名称的类型”错误，例如:

could not get type for name com.my.services.sample.MyClass from any class loader

然后，PermitAll Classes 列表正确生成，但 PermitAll 方法列表失败并出现异常，例如:

Execution failed for task ':mytask'.

> org/dom4j/DocumentException

我已经使用以下内容作为指南，但无法取得任何进一步的进展:
https://discuss.gradle.org/t/gradle-plugin-with-reflections/22690
Reflections could not get class type

Answer 1

您应该使用以下内容来创建类加载器

URL[] urls = project.sourceSets.main.runtimeClasspath.files.collect {
    it.toURI().toURL()
} as URL[]
ClassLoader classloader = new URLClassLoader(urls, null)