【第四十章】Spring Boot 自定义拦截器

1.首先编写拦截器代码

package com.sarnath.interceptor;

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

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

import com.sarnath.constants.Constants;
import com.sarnath.controller.BaseController;
import com.sarnath.dto.output.UserOutput;

/**
 * 自定义拦截器
 * @Description
 * @author Sunny
 * @date 2018年1月15日
 */
@Service
public class CustomerInterceptor extends BaseController implements HandlerInterceptor {

    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        String url = request.getRequestURI().substring(1,request.getRequestURI().length()-1);

        /**登录和退出登录不做拦截*/
        if(noLoginUrl.contains(url)){
            return true;
        }
        //判断用户是否已登录
        UserOutput user = getLoginUser(request, response);
        if(user == null || user.getUserId() == null){
            response.sendRedirect("/index");
            return false;
        }
        //判断当前用户请求路径是否拥有对应权限
        boolean allowRequesst = false;
        if(user.getUserType() == Constants.USER_TYPE_ADMIN){
            if(adminUrl.contains(url)){
                allowRequesst = true;
            }
        }else if(user.getUserType() == Constants.USER_TYPE_TEACHER){
            if(teacherUrl.contains(url)){
                allowRequesst = true;
            }
        }else if(user.getUserType() == Constants.USER_TYPE_STUDENT){
            if(studentUrl.contains(url)){
                allowRequesst = true;
            }
        }
        if(allowRequesst){
            return allowRequesst;
        }

        //默认跳转到登录页面
        response.sendRedirect("/index");
        return false;
    }

    @Override
    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {

    }

    @Override
    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {

    }

}

2.将拦截器增加到Spring Boot配置中

package com.sarnath.config;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;

import com.sarnath.interceptor.CustomerInterceptor;

@Configuration
public class InterceptorConfig extends WebMvcConfigurerAdapter {
    @Autowired
    private CustomerInterceptor interceptor;
    /**
     * 添加拦截器到Spring Boot配置中
     */
    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        registry.addInterceptor(interceptor).addPathPatterns("/**");
    }
}

Ok，只需要这两部，设置好方法或路径的拦截业务逻辑即可