pf4j 注入spring controller 的几种方法

核心还是基于RequestMappingHandlerMapping bean 进行controller 的创建

方法一

获取RequestMappingHandlerMapping bean 注册registerMapping
参考(参考伪代码)

 

getMappingForMethod = ReflectionUtils.findMethod(RequestMappingHandlerMapping.class, "getMappingForMethod", Method.class, Class.class);

 

Controller annotation = aClass.getAnnotation(Controller.class);

if(annotation != null) {

    Object bean = <getPluginApplicationContext()>.getBean(aClass); // use parent context( PluginManager)

    Method[] methods = aClass.getMethods();

    for (Method method : methods) {

        if (method.getAnnotation(RequestMapping.class) != null

                || method.getAnnotation(GetMapping.class) != null

                || method.getAnnotation(PostMapping.class) != null) {

            RequestMappingInfo requestMappingInfo = (RequestMappingInfo) getMappingForMethod.invoke(requestMappingHandlerMapping, method, aClass);

            requestMappingHandlerMapping.registerMapping(requestMappingInfo, bean, method);

        }

    }

}

方法二

自己实现AbstractHandlerMapping ，注册一个自己的WebMvcRegistrations bean 对于spring boot 可以直接实现WebMvcRegistrations
参考

 

@Bean

@ConditionalOnMissingBean(WebMvcRegistrations.class)

public WebMvcRegistrations mvcRegistrations() {

    return new WebMvcRegistrations() {

        @Override

        public RequestMappingHandlerMapping getRequestMappingHandlerMapping() {

            return new <custom>RequestMappingHandlerMapping();

        }

 

        @Override

        public RequestMappingHandlerAdapter getRequestMappingHandlerAdapter() {

            return null;

        }

 

        @Override

        public ExceptionHandlerExceptionResolver getExceptionHandlerExceptionResolver() {

            return null;

        }

    };

}

自定义RequestMappingHandlerMapping 实现一个基于注解注册controller 的方法，这样在处理阶段就比较方便了

public void registerControllers(SpringBootPlugin springBootPlugin) {

    getControllerBeans(springBootPlugin).forEach(bean -> registerController(springBootPlugin, bean));

}

 

private void registerController(SpringBootPlugin springBootPlugin, Object controller) {

    String beanName = controller.getClass().getName();

    // unregister RequestMapping if already registered

    unregisterController(springBootPlugin.getMainApplicationContext(), controller);

    springBootPlugin.registerBeanToMainContext(beanName, controller);

    detectHandlerMethods(controller);

}

注意bean 也是注册到main context 基于此方法的好处是能够更好的利用detectHandlerMethods
进行handler 的处理，与上边实际是类似的，但是更加符合spring 的处理机制

说明

对于resource 的处理，我们也可以自己实现一个PathResourceResolver，扩展WebMvcConfigurer
添加一个自己的resourcehandler

 

default void addResourceHandlers(ResourceHandlerRegistry registry) {

}

sbp 的一些实现是很值得借鉴参考的

参考资料

https://github.com/hank-cp/sbp
https://gitee.com/dianbuapp_admin/jeegot