Springboot之如何使用interceptor拦截器

在这里我就不细说它的原理什么的了,具体原理看这个Filter和拦截器的区别

https://blog.csdn.net/kxj19980524/article/details/85316586

SpringBoot使用步骤

先创建一个interceptor实现HandlerInterceptor,或者继承HandlerInterceptorAdapter并且让ioc管理,一般使用实现的方式.

package com.buba.interceptor;

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

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

@Component
public class OneInterceptor implements HandlerInterceptor {

    //目标方法执行前执行,
    //return false,目标方法就不执行了
    //如果方法发生异常,后面的程序也不会执行了
    @Override
    public boolean preHandle(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o) throws Exception {
        System.out.println("目标方法执行前执行");
        return true;
    }
    //目标方法执行后执行
    //在视图解析器前执行
    //可以在这里更改返回到哪个视图,因为方法的参数带有modelandview
    @Override
    public void postHandle(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o, ModelAndView modelAndView) throws Exception {
        System.out.println("目标方法后,视图解析器前执行");
    }

    //目标方法后,试图解析器后,
    // 这里可得到执行controller时的异常信息
    // 这里可记录操作日志
    @Override
    public void afterCompletion(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o, Exception e) throws Exception {
        System.out.println("目标方法后,视图解析器后执行");
    }
} 

然后写一个配置类继承WebMvcConfigurerAdapter类，并重写addInterceptors()方法,把自己写的拦截器注入进去, 然后方法拦截器注册类中,就可以使用了

package com.buba.configuration;

        import org.springframework.beans.factory.annotation.Autowired;
        import org.springframework.boot.SpringBootConfiguration;
        import org.springframework.web.servlet.HandlerInterceptor;
        import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
        import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;

@SpringBootConfiguration
public class InterceptorConfiguration extends WebMvcConfigurerAdapter {
    @Autowired
    private HandlerInterceptor interceptor;

    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        registry.addInterceptor(interceptor).addPathPatterns("/**").excludePathPatterns("");
        //addPathPatterns("/**")  这是拦截那些路径
        //excludePathPatterns("")这是放行那些路径,可以加多个这方法,接着点就行
    }
}

SpringMVC使用步骤 

还是创建一个拦截器类跟上面一样

然后在springmvc的配置文件中加拦截器的配置

<!-- 配置拦截器-->
 <mvc:interceptors>
    <!-- 权限拦截器-->
     <mvc:interceptor>
         <mvc:mapping path="/**"/>
         <!--放行静态资源-->
         <mvc:exclude-mapping path="/css/**"/>
         <mvc:exclude-mapping path="/demo/**"/>
         <mvc:exclude-mapping path="/easyUI/**"/>
         <mvc:exclude-mapping path="/images/**"/>
         <mvc:exclude-mapping path="/js/**"/>
         <ref bean="loginInterceptor"/>   //这个是把自己定义的拦截器注入进来
     </mvc:interceptor>
 </mvc:interceptors>