SpringBoot复习：（61）拦截器(HandlerInterceptor）的用法

一、自定义拦截器：

package cn.edu.tju.interceptor;import org.springframework.stereotype.Component;
import org.springframework.web.servlet.HandlerInterceptor;import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;public class MyInterceptor implements HandlerInterceptor {public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler)throws Exception {System.out.println("Servlet path is : " +request.getServletPath());return true;}
}

二、通过WebMvcConfigurer配置拦截器

package cn.edu.tju.config;import cn.edu.tju.component.MyDateConverter;
import cn.edu.tju.interceptor.MyInterceptor;
import org.springframework.context.annotation.Configuration;
import org.springframework.format.FormatterRegistry;
import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;@Configuration
public class MyWebMvcConfig implements WebMvcConfigurer {@Overridepublic void addInterceptors(InterceptorRegistry registry) {registry.addInterceptor(new MyInterceptor());}
}

异常时，postHandle不会执行。afterCompletion会执行

过滤器先于拦截器执行。

package cn.edu.tju.config;import org.springframework.stereotype.Component;import javax.servlet.*;
import java.io.IOException;@Component
public class MyFilter implements Filter {@Overridepublic void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {System.out.println("in my filter【before]......");chain.doFilter(request, response);System.out.println("in my filter【after】......");}public void destroy() {System.out.println("after response......");}
}

package cn.edu.tju;import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.web.servlet.ServletComponentScan;
import org.springframework.scheduling.annotation.EnableScheduling;@SpringBootApplication
@EnableScheduling
@ServletComponentScan
public class Start {public static void main(String[] args) {SpringApplication.run(Start.class, args);}
}