spring 自定义注解（HandlerInterceptor实现）
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使用示例
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自定义注解实现对controller层对标注了该注解的方法统计请求次数???????????
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CustomAnnotation
@Documented
@Retention(RetentionPolicy.RUNTIME)
public @interface CustomAnnotation {
}
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CustomHandlerInterceptor
@Component
public class CustomHandlerInterceptor implements HandlerInterceptor {
private Map<String,Integer> count = new HashMap<>();
@Override
public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
HandlerMethod handlerMethod = (HandlerMethod) handler;
Method method = handlerMethod.getMethod();
if (method.isAnnotationPresent(CustomAnnotation.class)){
String requestURI = request.getRequestURI();
if (requestURI!=null || !"".equals(requestURI)){
if (count.containsKey(requestURI)){
count.put(requestURI,count.get(requestURI)+1);
}else {
count.put(requestURI,1);
}
}
System.out.println(requestURI+"请求次数为："+count.get(requestURI));
}
return HandlerInterceptor.super.preHandle(request, response, handler);
}
}
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WebConfig
@Configuration
public class WebConfig implements WebMvcConfigurer {
@Resource
private CustomHandlerInterceptor customHandlerInterceptor;
@Override
public void addInterceptors(InterceptorRegistry registry) {
registry.addInterceptor(customHandlerInterceptor).addPathPatterns("/**");
}
}
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HelloController
@RestController
public class HelloController {
@CustomAnnotation
@RequestMapping("/hello")
public String hello(){
return "hello";
}
@RequestMapping("/hello2")
public String hello2(){
return "hello2";
}
}
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使用测试
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localhost:8080/hello：连续点击两次，控制台输出
2022-04-25 13:46:12.268 INFO 1935 --- [ main] w.s.c.ServletWebServerApplicationContext : Root WebApplicationContext: initialization completed in 858 ms
2022-04-25 13:46:12.561 INFO 1935 --- [ main] o.s.b.w.embedded.tomcat.TomcatWebServer : Tomcat started on port(s): 8080 (http) with context path ''
2022-04-25 13:46:12.570 INFO 1935 --- [ main] com.example.demo.DemoApplication : Started DemoApplication in 1.489 seconds (JVM running for 2.096)
2022-04-25 13:46:16.786 INFO 1935 --- [nio-8080-exec-1] o.a.c.c.C.[Tomcat].[localhost].[/] : Initializing Spring DispatcherServlet 'dispatcherServlet'
2022-04-25 13:46:16.786 INFO 1935 --- [nio-8080-exec-1] o.s.web.servlet.DispatcherServlet : Initializing Servlet 'dispatcherServlet'
2022-04-25 13:46:16.787 INFO 1935 --- [nio-8080-exec-1] o.s.web.servlet.DispatcherServlet : Completed initialization in 0 ms
/hello请求次数为：1
/hello请求次数为：2
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localhost:8080/hello2：控制台无输出
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