拦截器在Spring Boot中如何使用

第一步，定义拦截器：

package com.zl.interceptor;

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

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

public class myInterceptor implements HandlerInterceptor {
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        System.out.println("preHandle");
        return true;
    }

    @Override
    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {
        System.out.println("preHandle");
    }

    @Override
    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {
        System.out.println("preHandle");
    }
}

控制台打印三个输出语句，作为测试。

第二步：配置拦截器

package com.zl.interceptor;

import org.springframework.context.annotation.Bean;
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) {
        registry.addInterceptor(myInterceptor()).addPathPatterns("/**");
    }
    @Bean
    myInterceptor myInterceptor(){
        return new myInterceptor();
    }
}

将定义的拦截器注入到这个配置方法中，并拦截所有路径。

第三步：写个接口测试

package com.zl.interceptor;

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

@RestController
public class helloController {
    @GetMapping("/hello")
    public String hello(){
        return "hello";
    }
}

测试结果

 定义的拦截器三个方法都执行了。