切面,注解，过滤器（结合使用以及避坑）

概述

使用切面|注解 在controller和filter 上面加权限注解，用来限制controller/filter转发的访问权限控制。

切面

@Aspect
@Component
public class LogAspect {

    @Around("execution(public * com..*Filter.*(..))")
    public Object doFilterAuthorization(ProceedingJoinPoint joinPoint) throws Throwable {
        MethodSignature signature = (MethodSignature)joinPoint.getSignature();
        MyTest annotation = signature.getMethod().getAnnotation(MyTest.class);
        String value = annotation.value();
        System.out.println(value);
        return joinPoint.proceed(joinPoint.getArgs());
    }

    @Around("execution(public * com..*Controller.*(..))")
    public Object doControllerAuthorization(ProceedingJoinPoint joinPoint) throws Throwable {
        MethodSignature signature = (MethodSignature)joinPoint.getSignature();
        MyTest annotation = signature.getMethod().getAnnotation(MyTest.class);
        String value = annotation.value();
        System.out.println(value);
        return joinPoint.proceed(joinPoint.getArgs());
    }

主类

@SpringBootApplication
@ServletComponentScan
public class Demo7Application {

    public static void main(String[] args) {
        SpringApplication.run(Demo7Application.class, args);
    }

}

注解

@Documented
@Retention(RetentionPolicy.RUNTIME)
@Target({ElementType.METHOD})
public @interface MyTest {

    String value();
}

一定要注意，如果注解灭有有上面哪些注解会在切面中获取不到对应注解对象。

Controller类

@RequestMapping("/test")
@RestController
public class TTController {

    @RequestMapping("/sad")
    @MyTest(value = "sad")
    public String getT() {
        return "sss";
    }

}

Filter

@WebFilter(urlPatterns = "/*")
public class CCFilter implements Filter {

    @Override
    @MyTest("sss")
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain)
        throws IOException, ServletException {
        System.out.println("sad");
        filterChain.doFilter(servletRequest, servletResponse);

    }
}

以上代码整体来说是没有问题的，但是为了项目好管理我们一般吧filter注入容器的方式改成@Bean的注入方式，以方便传参等等。

@Configuration
public class CasFilterBeanConfig {

    @Bean
    public FilterRegistrationBean<CCFilter> validateServiceTickteFilter() {
        FilterRegistrationBean<CCFilter> registration = new FilterRegistrationBean<>();
        registration.setFilter(new CCFilter());
        registration.addUrlPatterns("/*");

        return registration;
    }
}

然后引入了问题就是，切面已经切不到filter的doFilter方法了。。