[Java知识库]拦截器参考案例

package interceptor;

import lombok.extern.slf4j.Slf4j;
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;

/**
 * @description: 全局拦截器
 * @author: lyk
 * @create: 2021/6/23 14:21
 */
@Slf4j
@Component
public class GlobalInterceptor implements HandlerInterceptor {

    // 在业务处理器处理请求之前被调用
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        //定义开始时间
        long start = System.currentTimeMillis();
        //2.将其存到请求域当中
        request.setAttribute("start",start);
        //记录请求日志
        log.info(request.getRequestURI()+",请求到达");
        //3,返回true，才会找下一个拦截器，如果没有下一个拦截器，则去Controller
        return true;
    }

    // 在业务处理器处理请求完成之后，生成视图之前执行
    @Override
    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {
        //1,取出start
        long start = (long) request.getAttribute("start");
        //2,得到end
        long end =System.currentTimeMillis();
        //3,记录耗时
        long spendTime = end-start;
        if (spendTime>2000){
            log.warn("方法耗时严重，请及时处理，耗时："+spendTime);
        }else {
            log.info("方法耗时"+spendTime+"毫秒，正常");
        }
    }

    // 在DispatcherServlet完全处理完请求之后被调用，可用于清理资源
    @Override
    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {
        log.info("88888888888888");

    }


}

package interceptor;

import lombok.extern.slf4j.Slf4j;
import org.springframework.lang.Nullable;
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;
import javax.servlet.http.HttpSession;

/**
 * @description: 用户登陆拦截器
 * @author: lyk
 * @create: 2021/6/23 16:26
 */
@Slf4j
@Component
public class UserLoginInterceptor implements HandlerInterceptor {
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        String uri = request.getRequestURI();
       /* if(uri.contains("wechat")||uri.contains("api")||uri.contains("wxuser")){
            return true;
        }*/
        Object user = request.getSession().getAttribute("user");
        if(!uri.contains("login")){
            if(user==null){
//                response.sendRedirect("http://xx.xx.xxx.xxx:7001/test/TestDemoServlet?userName=zhangsan");
                response.sendRedirect("https://www.baidu.com/");
                return false;

            }
        }else{
            if(user!=null){
                response.sendRedirect("/main/index");
                return false;
            }
        }
        return true;



//        HttpSession session = request.getSession(true);
//        Object username=session.getAttribute("userguid");
//        if(null!=username) {//已登录
//            return true;
//        }else {//未登录
//            //直接重定向到登录页面
//            //response.sendRedirect(request.getContextPath()+"/wechatplatformuser/loginRBAC.html");
//            return false;
//        }
    }

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

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

}

package interceptor;

import lombok.extern.slf4j.Slf4j;
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.WebMvcConfigurer;

/**
 * @description: 拦截器配置添加
 * @author: lvyk
 * @create: 2021/6/23 14:37
 */
@Slf4j
@Configuration
public class WebMvcConfig implements WebMvcConfigurer {

    @Autowired
    private GlobalInterceptor globalInterceptor;

    @Autowired
    private UserLoginInterceptor userLoginInterceptor;

    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        //这里添加拦截器的顺序就是拦截器执行的顺序
        registry.addInterceptor(userLoginInterceptor)
                .addPathPatterns("/**")
                .addPathPatterns("/api/**")
                .excludePathPatterns("/swagger-resources/**", "/webjars/**", "/v2/**", "/swagger-ui.html/**");;
        registry.addInterceptor(globalInterceptor).addPathPatterns("/api/**");
        log.info("添加拦截器成功...");

    }
//    @Override
//    public void addInterceptors(InterceptorRegistry registry) {
//        // 添加拦截器，配置拦截地址
//        registry.addInterceptor(interceptor).addPathPatterns("/api/**");
//    }

}