前端提交表单按钮如果不小心按了两次或者多次,那么表单数据就被重复插入数据库,尤其是网络延时的情况下,多次点击提交按钮是常有的事,那么后端怎么来避免这个问题呢,最好的办法就是通过注解+拦截器验证重复的表单
1、添加注解接口
@Inherited
@Target(ElementType.METHOD)
@Retention(RetentionPolicy.RUNTIME)
@Documented
public @interface RepeatSubmit
{
}
2、添加RepeatSubmitInterceptor防止重复提交拦截器,验证是否重复提交由子类实现具体的防重复提交的规则
/**
* 防止重复提交拦截器
*
* @author driver-IT
*/
@Component
public abstract class RepeatSubmitInterceptor extends HandlerInterceptorAdapter
{
@Override
public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception
{
if (handler instanceof HandlerMethod)
{
HandlerMethod handlerMethod = (HandlerMethod) handler;
Method method = handlerMethod.getMethod();
RepeatSubmit annotation = method.getAnnotation(RepeatSubmit.class);
if (annotation != null)
{
if (this.isRepeatSubmit(request))
{
AjaxResult ajaxResult = AjaxResult.error("不允许重复提交,请稍后再试");
ServletUtils.renderString(response, JSONObject.toJSONString(ajaxResult));
return false;
}
}
return true;
}
else
{
return super.preHandle(request, response, handler);
}
}
/**
* 验证是否重复提交由子类实现具体的防重复提交的规则
*
* @param httpServletRequest
* @return
* @throws Exception
*/
public abstract boolean isRepeatSubmit(HttpServletRequest request);
}
3、添加子类实现具体的防重复提交的规则
/**
* 判断请求url和数据是否和上一次相同,
* 如果和上次相同,则是重复提交表单。 有效时间为10秒内。
*
* @author driver-IT
*/
@Component
public class SameUrlDataInterceptor extends RepeatSubmitInterceptor
{
public final String REPEAT_PARAMS = "repeatParams";
public final String REPEAT_TIME = "repeatTime";
public final String CACHE_REPEAT_KEY = "repeatData";
@Autowired
private RedisCache redisCache;
/**
* 间隔时间,单位:秒 默认10秒
*
* 两次相同参数的请求,如果间隔时间大于该参数,系统不会认定为重复提交的数据
*/
private int intervalTime = 10;
public void setIntervalTime(int intervalTime)
{
this.intervalTime = intervalTime;
}
@SuppressWarnings("unchecked")
@Override
public boolean isRepeatSubmit(HttpServletRequest request)
{
RepeatedlyRequestWrapper repeatedlyRequest = (RepeatedlyRequestWrapper) request;
String nowParams = HttpHelper.getBodyString(repeatedlyRequest);
// body参数为空,获取Parameter的数据
if (StringUtils.isEmpty(nowParams))
{
nowParams = JSONObject.toJSONString(request.getParameterMap());
}
Map<String, Object> nowDataMap = new HashMap<String, Object>();
nowDataMap.put(REPEAT_PARAMS, nowParams);
nowDataMap.put(REPEAT_TIME, System.currentTimeMillis());
// 请求地址(作为存放cache的key值)
String url = request.getRequestURI();
Object sessionObj = redisCache.getCacheObject(CACHE_REPEAT_KEY);
if (sessionObj != null)
{
Map<String, Object> sessionMap = (Map<String, Object>) sessionObj;
if (sessionMap.containsKey(url))
{
Map<String, Object> preDataMap = (Map<String, Object>) sessionMap.get(url);
if (compareParams(nowDataMap, preDataMap) && compareTime(nowDataMap, preDataMap))
{
return true;
}
}
}
Map<String, Object> cacheMap = new HashMap<String, Object>();
cacheMap.put(url, nowDataMap);
redisCache.setCacheObject(CACHE_REPEAT_KEY, cacheMap, intervalTime, TimeUnit.SECONDS);
return false;
}
/**
* 判断参数是否相同
*/
private boolean compareParams(Map<String, Object> nowMap, Map<String, Object> preMap)
{
String nowParams = (String) nowMap.get(REPEAT_PARAMS);
String preParams = (String) preMap.get(REPEAT_PARAMS);
return nowParams.equals(preParams);
}
/**
* 判断两次间隔时间
*/
private boolean compareTime(Map<String, Object> nowMap, Map<String, Object> preMap)
{
long time1 = (Long) nowMap.get(REPEAT_TIME);
long time2 = (Long) preMap.get(REPEAT_TIME);
if ((time1 - time2) < (this.intervalTime * 1000))
{
return true;
}
return false;
}
4、找到你要防止重复提交的接口controller中添加这个注解,搞定收工,亲测有效
/**
* 新增设备
*/
@RepeatSubmit
@ApiOperation("新增设备")
@ApiImplicitParam(name = "device", value = "新增设备信息", dataType = "Device")
@PreAuthorize("@ss.hasPermi('dev:device:add')")
@PostMapping
public AjaxResult add(@RequestBody Device device)
{
if (device == null || device.getDeptId() == null) {
return AjaxResult.error("请选择部门");
}
LoginUser loginUser = tokenService.getLoginUser(ServletUtils.getRequest());
if (!deptService.hasChildOrSelfByDeptId(device.getDeptId(), loginUser.getUser().getDeptId())) {
return new AjaxResult(409, "不允许跨区域操作");
}
return toAjax(deviceService.insertDevice(device));
}