1.pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.5.5</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.yl</groupId>
    <artifactId>interceptor</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>interceptor</name>
    <description>Demo project for Spring Boot</description>
    <properties>
        <java.version>1.8</java.version>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

</project>

2.自定义拦截器

package com.yl.interceptor.interceptor;

import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/** * 自定义拦截器 */
public class MyInterceptor implements HandlerInterceptor {

    /** * 发起请求前调用 * 该方法返回false的话，将不会往下执行 * @param request * @param response * @param handler * @return * @throws Exception */
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        System.out.println("preHandle......");
        return true;
    }

    /** * 该方法在调用controller方法后，DispatcherServlet渲染视图之前被执行 * * @param request * @param response * @param handler * @param modelAndView * @throws Exception */
    @Override
    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {
        System.out.println("postHandle.....");
    }

    /** * preHandle()返回true后，afterCompletion()才会执行 * @param request * @param response * @param handler * @param ex * @throws Exception */
    @Override
    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {
        System.out.println("afterCompletion.....");
    }
}

3.自定义配置类

package com.yl.interceptor.config;

import com.yl.interceptor.interceptor.MyInterceptor;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;

@Configuration
public class WebMvcConfig implements WebMvcConfigurer {
    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        //设置拦截路径，排除路径，优先级等。。。
        registry.addInterceptor(new MyInterceptor()).addPathPatterns("/**")
                .excludePathPatterns("/say").order(11);
    }
}

4.测试用到的controller

package com.yl.interceptor.controller;

import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;

@RestController
public class HelloController {
    @GetMapping("/hello")
    public String hello() {
        System.out.println("hello interceptor!!!!!!");
        return "hello interceptor";
    }

    @GetMapping("/say")
    public String say() {
        return "say....";
    }
}

5.结果

只有当发起hello请求时，才会走自定义拦截器里的方法，发起say请求时并没有走自定义拦截器的方法！