spring MVC获取所有的controller

前言

因为spring 和spring mvc 使用的管理容器不同，所以获取bean的方式也就不同
spring 的bean是交由ApplicationContext 管理
spring mvc的bean是交由WebApplicationContext 管理，
所以物品们需要先获取WebApplicationContext,话不多说上代码

第一步获取WebApplicationContext

通过WebApplicationContextUtils 工具类中的public static WebApplicationContext getWebApplicationContext(ServletContext sc) 方法获取WebApplicationContext,所以，想要获取，就必须传入ServletContext对象
获取ServletContext对象可以从FilterConfig,ServletRequest等中获取

@Override
public void init(FilterConfig filterConfig) throws ServletException {
    WebApplicationContext webApplicationContext = WebApplicationContextUtils.getWebApplicationContext(filterConfig.getServletContext());
}

public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception{
    WebApplicationContext webApplicationContext = WebApplicationContextUtils.getWebApplicationContext(request.getServletContext());
}

第二步获取带有controller 注解的bean

WebApplicationContext webApplicationContext = WebApplicationContextUtils.getWebApplicationContext(filterConfig.getServletContext());
//获取所有带controller的类
Map<String, Object> controllerBeans = webApplicationContext.getBeansWithAnnotation(Controller.class);
//遍历Map
Iterator<Map.Entry<String, Object>> iterator = controllerBeans.entrySet().iterator();
while (iterator.hasNext()) {
    Map.Entry<String, Object> next = iterator.next();
    //获取controller类
    Object value = next.getValue();
    
    Class<?> controllerClass = value.getClass();
    //判断是否有RequestMapping注解
    RequestMapping controllerAnno = controllerClass.getAnnotation(RequestMapping.class);

    //获取name和path
    String classMappingName=controllerClass.getSimpleName();
    String[] classMappingPaths = {};
    //保存controller类的mapping
    if (controllerAnno!=null) {
        //获取name和path
        classMappingName=controllerAnno.name();
        classMappingPaths = controllerAnno.path();
    }
    //获取所有的方法
    Method[] methods = controllerClass.getMethods();
    for (Method method : methods) {
        RequestMapping methodAnno = method.getAnnotation(RequestMapping.class);
        if (methodAnno!=null) {
            //获取name和path
            String methodMappingName=methodAnno.name();
            String[] methodMappingPaths = methodAnno.path();
        }
    }
}

注意

1. WebApplicationContext 只能获取ApplicationContext扫描的bean，spring mvc 扫描的bean不能获取，如果想获取spring mvc 扫描的bean，就必须保证ApplicationContext扫描了该bean，
2. 因为spring 和spring mvc使用的是两个不同的容器，所以spring扫描spring mvc 扫描的bean不存在重复注入的问题
3. 如果存在不能获取dao bean时，需要检查mybtis spring中MapperScannerConfigurer中dao层包路径是否正确

<bean class="org.mybatis.spring.mapper.MapperScannerConfigurer" p:basePackage="正确的dao层包路径"
          p:sqlSessionFactoryBeanName="sqlSessionFactory"/>