简介
拦截器我想大家都并不陌生，最常用的登录拦截、权限校验、防重复提交、记录日志等等,总之可以去做很多的事情。
自定义拦截器HandlerInterceptorAdapter
我们以记录日志为例，介绍拦截器
1. preHandle：在业务处理器处理请求之前被调用，调用controller之前调用。预处理，可以进行编码、安全控制、权限校验等处理；
2. postHandle：在业务处理器处理请求执行完成后，生成视图之前执行。后处理（调用了Service并返回ModelAndView，但未进行页面渲染），有机会修改ModelAndView ；
3. afterCompletion：在DispatcherServlet完全处理完请求后被调用，可用于清理资源等。import java.util.HashMap; import java.util.Map; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import org.springframework.stereotype.Component; import org.springframework.web.method.HandlerMethod; import org.springframework.web.servlet.ModelAndView; import org.springframework.web.servlet.handler.HandlerInterceptorAdapter; import com.alibaba.fastjson.JSON; import com.example.demo.util.RespUtil; @Component public class ReqInterceptor extends HandlerInterceptorAdapter { /** * 在方法被调用前执行。在该方法中可以做类似校验的功能。如果返回true， * 则继续运行下去。如果返回false，则中断执行。 */ @Override public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception { log.info("进入调单方法controller层之前"); String insuranceId = httpServletRequest.getParameter("insuranceId"); try { FanHuaBack fanHuaBackOld = insureListService.getinsure(insuranceId); String oldData = JSON.toJSONString(fanHuaBackOld); httpServletRequest.setAttribute("dataBefore", oldData); super.preHandle(httpServletRequest,httpServletResponse,o); } catch (Exception e) { log.error("车险投保信息查询异常", e.getMessage()); } finally { return true; } } /** * 在方法执行后调用。 */ @Override public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView)
throws Exception { log.info("进入调单方法controller层之后-----------日志记录开始"); InsuranceOperatLog insuranceOperatLog = new InsuranceOperatLog();//日志类 int status = 0; try { //从request请求中获取信息 String requestURI = httpServletRequest.getRequestURI(); String insuranceId = httpServletRequest.getParameter("insuranceId"); String empNo = httpServletRequest.getParameter("empNo"); String empName = httpServletRequest.getParameter("empName"); int opeStatus = (int) httpServletRequest.getAttribute("status"); FanHuaBack fanHuaBackNew = insureListService.getinsure(insuranceId); String newData = JSON.toJSONString(fanHuaBackNew); String oldData = (String) httpServletRequest.getAttribute("dataBefore"); Map<String, String> map = new HashMap<>(); map.put("empNum", empNo); map.put("empName", empName); map.put("insuranceId", insuranceId); String reqObj = JSON.toJSONString(map); insuranceOperatLog.setInsuranceId(insuranceId); insuranceOperatLog.setCreateTime(DateUtil.format(new Date(), DateUtil.Formatter.yyyyMMddHHmmss)); insuranceOperatLog.setDataBefore(oldData); insuranceOperatLog.setDataAfter(newData); insuranceOperatLog.setReq_json(reqObj); insuranceOperatLog.setReq_url(requestURI); insuranceOperatLog.setOperatorType("调单"); insuranceOperatLog.setStatus(opeStatus == 1 ? "成功" : "失败"); SysUser sysUser = (SysUser) SecurityUtils.getSubject().getPrincipal(); if (sysUser != null) { insuranceOperatLog.setOperatorName(sysUser.getLoginName()); insuranceOperatLog.setOperatorNo(sysUser.getUserNo()); } insuranceOperatRepository.save(insuranceOperatLog); super.postHandle(httpServletRequest,httpServletResponse,o,modelAndView); } catch (Exception ex) { log.error("调单操作异常日志保存异常{}", ex.getMessage()); } log.info("调单操作日志记录结束{}"); } /** * 在整个请求处理完毕后进行回调，也就是说视图渲染完毕或者调用方已经拿到响应。 */ @Override public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex)
throws Exception { System.out.println("在整个请求处理完毕后进行回调"); super.afterCompletion(request, response, handler, ex); } }