【异常(待解决)】org.apache.http.NoHttpResponseException: api.weixin.qq.com:443 failed to respond...

一、记录下异常堆栈信息

2019-06-01 10:26:58.246 [http-nio-9850-exec-3] ERROR weixin.popular.client.LocalHttpClient - execute error
org.apache.http.NoHttpResponseException: api.weixin.qq.com:443 failed to respondat org.apache.http.impl.conn.DefaultHttpResponseParser.parseHead(DefaultHttpResponseParser.java:141)at org.apache.http.impl.conn.DefaultHttpResponseParser.parseHead(DefaultHttpResponseParser.java:56)at org.apache.http.impl.io.AbstractMessageParser.parse(AbstractMessageParser.java:259)at org.apache.http.impl.DefaultBHttpClientConnection.receiveResponseHeader(DefaultBHttpClientConnection.java:163)at org.apache.http.impl.conn.CPoolProxy.receiveResponseHeader(CPoolProxy.java:165)at org.apache.http.protocol.HttpRequestExecutor.doReceiveResponse(HttpRequestExecutor.java:273)at org.apache.http.protocol.HttpRequestExecutor.execute(HttpRequestExecutor.java:125)at org.apache.http.impl.execchain.MainClientExec.execute(MainClientExec.java:272)at org.apache.http.impl.execchain.ProtocolExec.execute(ProtocolExec.java:185)at org.apache.http.impl.execchain.RetryExec.execute(RetryExec.java:89)at org.apache.http.impl.execchain.RedirectExec.execute(RedirectExec.java:111)at org.apache.http.impl.client.InternalHttpClient.doExecute(InternalHttpClient.java:185)at org.apache.http.impl.client.CloseableHttpClient.execute(CloseableHttpClient.java:72)at org.apache.http.impl.client.CloseableHttpClient.execute(CloseableHttpClient.java:221)at org.apache.http.impl.client.CloseableHttpClient.execute(CloseableHttpClient.java:165)at weixin.popular.client.LocalHttpClient.execute(LocalHttpClient.java:135)at weixin.popular.client.LocalHttpClient.executeJsonResult(LocalHttpClient.java:156)at weixin.popular.api.MessageAPI.messageCustomSend(MessageAPI.java:58)at weixin.popular.api.MessageAPI.messageCustomSend(MessageAPI.java:70)at com.xinchan.xcauto.merchants.common.service.local.WechatManager.sendWechantTextMessageToOa(WechatManager.java:85)at com.xinchan.xcauto.merchants.common.service.impl.FeignServiceImpl.sendOpenIdMessage(FeignServiceImpl.java:589)at com.xinchan.xcauto.merchants.common.service.impl.FeignServiceImpl.sendCouponMassage(FeignServiceImpl.java:177)at com.xinchan.xcauto.merchants.common.service.impl.FeignServiceImpl$$FastClassBySpringCGLIB$$e3661481.invoke(<generated>)at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:204)at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:684)at com.xinchan.xcauto.merchants.common.service.impl.FeignServiceImpl$$EnhancerBySpringCGLIB$$2747d965.sendCouponMassage(<generated>)at com.xinchan.xcauto.merchants.common.controller.FeignController.sendCouponMassage(FeignController.java:43)at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)at java.lang.reflect.Method.invoke(Method.java:498)at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:209)at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:136)at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:102)at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:877)at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:783)at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87)at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:991)at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:925)at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:974)at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:877)at javax.servlet.http.HttpServlet.service(HttpServlet.java:661)at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:851)at javax.servlet.http.HttpServlet.service(HttpServlet.java:742)at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231)at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)at org.springframework.boot.actuate.metrics.web.servlet.WebMvcMetricsFilter.filterAndRecordMetrics(WebMvcMetricsFilter.java:158)at org.springframework.boot.actuate.metrics.web.servlet.WebMvcMetricsFilter.filterAndRecordMetrics(WebMvcMetricsFilter.java:126)at org.springframework.boot.actuate.metrics.web.servlet.WebMvcMetricsFilter.doFilterInternal(WebMvcMetricsFilter.java:111)at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)at org.springframework.boot.actuate.web.trace.servlet.HttpTraceFilter.doFilterInternal(HttpTraceFilter.java:90)at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)at com.xinchan.xcauto.core.config.filter.HttpServletRequestReplacedFilter.doFilter(HttpServletRequestReplacedFilter.java:32)at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:99)at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)at org.springframework.web.filter.HttpPutFormContentFilter.doFilterInternal(HttpPutFormContentFilter.java:109)at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)at org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:93)at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)at org.springframework.session.web.http.SessionRepositoryFilter.doFilterInternal(SessionRepositoryFilter.java:147)at org.springframework.session.web.http.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:81)at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:200)at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:198)at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96)at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:496)at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140)at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:81)at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87)at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:342)at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:803)at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66)at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:790)at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1468)at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)at java.lang.Thread.run(Thread.java:748)
2019-06-01 10:26:58.247 [http-nio-9850-exec-3] ERROR c.x.xcauto.common.controller.BaseControllerAdvice - 检测到未捕捉异常:IP:172.21.0.1 invoke url:http://172.17.244.191:9850/common/sendCouponMassage/v1 Exception:public class java.lang.NullPointerException
java.lang.NullPointerException: nullat com.xinchan.xcauto.merchants.common.service.local.WechatManager.sendWechantTextMessageToOa(WechatManager.java:86)at com.xinchan.xcauto.merchants.common.service.impl.FeignServiceImpl.sendOpenIdMessage(FeignServiceImpl.java:589)at com.xinchan.xcauto.merchants.common.service.impl.FeignServiceImpl.sendCouponMassage(FeignServiceImpl.java:177)at com.xinchan.xcauto.merchants.common.service.impl.FeignServiceImpl$$FastClassBySpringCGLIB$$e3661481.invoke(<generated>)at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:204)at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:684)at com.xinchan.xcauto.merchants.common.service.impl.FeignServiceImpl$$EnhancerBySpringCGLIB$$2747d965.sendCouponMassage(<generated>)at com.xinchan.xcauto.merchants.common.controller.FeignController.sendCouponMassage(FeignController.java:43)at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)at java.lang.reflect.Method.invoke(Method.java:498)at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:209)at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:136)at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:102)at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:877)at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:783)at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87)at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:991)at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:925)at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:974)at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:877)at javax.servlet.http.HttpServlet.service(HttpServlet.java:661)at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:851)at javax.servlet.http.HttpServlet.service(HttpServlet.java:742)at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231)at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)at org.springframework.boot.actuate.metrics.web.servlet.WebMvcMetricsFilter.filterAndRecordMetrics(WebMvcMetricsFilter.java:158)at org.springframework.boot.actuate.metrics.web.servlet.WebMvcMetricsFilter.filterAndRecordMetrics(WebMvcMetricsFilter.java:126)at org.springframework.boot.actuate.metrics.web.servlet.WebMvcMetricsFilter.doFilterInternal(WebMvcMetricsFilter.java:111)at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)at org.springframework.boot.actuate.web.trace.servlet.HttpTraceFilter.doFilterInternal(HttpTraceFilter.java:90)at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)at com.xinchan.xcauto.core.config.filter.HttpServletRequestReplacedFilter.doFilter(HttpServletRequestReplacedFilter.java:32)at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:99)at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)at org.springframework.web.filter.HttpPutFormContentFilter.doFilterInternal(HttpPutFormContentFilter.java:109)at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)at org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:93)at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)at org.springframework.session.web.http.SessionRepositoryFilter.doFilterInternal(SessionRepositoryFilter.java:147)at org.springframework.session.web.http.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:81)at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:200)at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:198)at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96)at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:496)at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140)at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:81)at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87)at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:342)at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:803)at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66)at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:790)at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1468)at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)at java.lang.Thread.run(Thread.java:748)
View Code

 

二、原因分析

1.官网解释是

org.apache.commons.httpclient.NoHttpResponseException:In some circumstances, usually when under heavy load, the web server may be able to receive requests but unable to process them.
A lack of sufficient resources like worker threads is a good example.
This may cause the server to drop the connection to the client without giving any response.
HttpClient
throws NoHttpResponseException when it encounters such a condition.
In most cases it is safe to retry a method that failed with NoHttpResponseException.

在某些情况下,通常是在高负载下,web服务器可能能够接收请求,但无法处理它们。缺乏足够的资源(比如工作线程)就是一个很好的例子。这可能导致服务器在不给出任何响应的情况下断开到客户机的连接。HttpClient在遇到这种情况时抛出NoHttpResponseException。在大多数情况下,重试使用NoHttpResponseException失败的方法是安全的。

官网给出的解决办法就是:重试调用失败的方法

 

2.自我验证及复现该问题到底什么情况下会发生(待定)

转载于:https://www.cnblogs.com/756623607-zhang/p/10960782.html

本文来自互联网用户投稿,该文观点仅代表作者本人,不代表本站立场。本站仅提供信息存储空间服务,不拥有所有权,不承担相关法律责任。如若转载,请注明出处:http://www.mzph.cn/news/411242.shtml

如若内容造成侵权/违法违规/事实不符,请联系多彩编程网进行投诉反馈email:809451989@qq.com,一经查实,立即删除!

相关文章

工作389-移动端控制

<meta name"viewport" content"widthdevice-width, initial-scale1.0,maximum-scale1.0, user-scalable0">

企业内容管理-互联网应用

企业内容管理-互联网应用 当你第一次听到企业内容管理这个名字&#xff0c;很容易联想到ERP这种复杂无比的系统。实际上也确实如此&#xff0c;目前几大主要的ECM系统都是复杂无比&#xff0c;所以我想从互联网应用&#xff0c;一般网民可以使用的角度来谈谈企业内容管理。 从…

计算机做游戏到大学要学什么,大学学什么专业,毕业才能从事电竞行业?

原标题&#xff1a;大学学什么专业&#xff0c;毕业才能从事电竞行业&#xff1f;电竞可不只是打游戏这么简单。想必最近很多同学已经陆陆续续收到录取通知书了&#xff0c;大学的美好生活已经在等着你们啦&#xff01;今天化学姐想和大家聊聊就业已经游戏行业相关的事儿。电子…

layui中table监听单元格_最全总结 | 聊聊 Python 办公自动化之 PPT(中)

点击上方 “AirPython”&#xff0c;选择 “加为星标”第一时间关注 Python 技术干货&#xff01;1. 前言上一篇文章简单地介绍了 PPT 的文档结构&#xff0c;并使用 python-pptx 这个依赖库完成对 PPT 文档最基本的操作最全总结 | 聊聊 Python 办公自动化之 PPT(上)作为 PPT 系…

工作383:css使absolute相对于父容器进行定位而不是以body(为什么绝对定位(absolute)的父级元素必须是相对定位(relative))...

借知乎的回答如下解释&#xff1a; 首先&#xff0c;我想告诉你的是&#xff0c;如果父级元素是绝对定位&#xff08;absolute&#xff09;或者没有设置&#xff0c;里面的绝对定位&#xff08;absolute&#xff09;自动以body定位。这句话是错的。 正确的是&#xff1a;只要父…

如何高效的清理系统盘空间?

我们一般会把系统安装在C盘&#xff0c;但是使用一段时间后会发现C盘的空间越来越少。尤其我们做开发的&#xff0c;会在电脑中装上很多软件的。比如我的机器上C盘空间 15G&#xff0c;平时安装软件时只要可以选择我都会把它装到其他盘的&#xff0c;但是半年下来&#xff0c;C…

东北考生到南方学计算机,为啥东北考生都想去南方,而南方学生很少考东北,看看他们怎么说...

原标题&#xff1a;为啥东北考生都想去南方&#xff0c;而南方学生很少考东北&#xff0c;看看他们怎么说文/晓宁说教育高考对于众多考生来说&#xff0c;是人生中最重要的一场考试&#xff0c;如果能在高考中发挥出好成绩&#xff0c;就可以顺利的考上一所自己理想的大学。按照…

[html] 如何给table中的某一列设置固定宽度

[html] 如何给table中的某一列设置固定宽度 table{ table-layout:fixed} table tr td:nth-child(n){width:100px}个人简介 我是歌谣&#xff0c;欢迎和大家一起交流前后端知识。放弃很容易&#xff0c; 但坚持一定很酷。欢迎大家一起讨论 主目录 与歌谣一起通关前端面试题

用excel制作双层饼图_双层饼图,让你的工作更出彩

在Excel中饼图是很常见的图表类型&#xff0c;做起来也很简单&#xff0c;相信大家都会做。但双层饼图你会做吗&#xff1f;如下图所示&#xff0c;根据左侧的数据源&#xff0c;做出右侧的双层饼图。这么漂亮的双层饼图是怎么制做出来的呢&#xff1f;今天我就来给大家分享一下…

Comet OJ - 2019 六一欢乐赛

传送门 #A&#xff1a; 思路&#xff1a;等差数列求和,看成俩次12… n,多加的n减去&#xff0c;所以 ans n*(n1) - n。 AC代码&#xff1a; 1 #include<iostream>2 #include<algorithm>3 #include<string>4 using namespace std;5 int main()6 {7 int n…

三个子系统_「正点原子Linux连载」第五十八章Linux INPUT子系统实验(一)

1)实验平台&#xff1a;正点原子Linux开发板2)摘自《正点原子I.MX6U嵌入式Linux驱动开发指南》关注官方微信号公众号&#xff0c;获取更多资料&#xff1a;正点原子第五十八章Linux INPUT子系统实按键、鼠标、键盘、触摸屏等都属于输入(input)设备&#xff0c;Linux内核为此专门…

湖南大学计算机与通信学院研究生,湖南大学计算机与通信学院2010年硕士研究生招生学科...

计算机考研学院简介计算机与通信学院前身为原湖南大学计算机科学系。1978年组建计算机教研室并开办计算机本科专业&#xff0c;1981年5月正式成立计算科学系&#xff0c;2001年10月正式成立计算机与通信学院。学院现有计算机应用技术博士授权点&#xff1b;计算机科学与技术、信…

【排序函数讲解】sort-C++

c标准库里的排序函数&#xff0c;用于对给定区间所有元素进行排序。头 文件是#include 使用 Sort&#xff08;&#xff09;在具体实现中规避了经典快速排序可能出现的、会导 致实际复杂度退化到 o&#xff08;n&#xff09;的极端情况。它根据具体情况使用不 同排序方法&#…

[html] HTML5拖拽事件的顺序是什么?

[html] HTML5拖拽事件的顺序是什么&#xff1f; ondragstart &#xff1a;源对象开始被拖动 ondrag&#xff1a;源对象被拖动过程中 ondragend&#xff1a;源对象被拖动结束ondragenter&#xff1a;源对象拖动着进入目标对象 ondragover&#xff1a;源对象拖动着悬停在目标对方…

【翻译】eXpressAppFramework QuickStart 业务模型设计(十)——在代码中实现数据验证...

这一讲&#xff0c;你将学到如何给业务对象和他们的属性设置规则。最终用户在执行赋值操作后将验证这些规则。你可以实现必填规则使得Position.Title属性不能为空。此规则将在Position对象保存的时候被验证。你还能够看到打破规则的界面提示。在此之前&#xff0c;我建议你去读…

注册机patch起什么作用_电机滑环起什么作用?

电机滑环起什么作用?发电机滑环就是我们传统的集电环&#xff0c;用于电机的换向器上作为导出导入电流的滑动接触体&#xff0c;它的导电、导热以及润滑性能良好&#xff0c;并具有一定的机械强度和换向性火花的本能。几乎所有的电机都使用碳刷&#xff0c;它是电机的重要组成…

统考计算机应用基础多少分及格,网络教育统考难吗?统考多少分及格?

我们可以知道网络教育统考科目主要就是考计算机和英语两个科目&#xff0c;一定是全部通过才能顺利拿到网络教育本科毕业证的。那么网络教育统考难吗&#xff1f;网络教育统考多少分及格&#xff1f;一、网络教育统考难吗网络教育统考难度实际上是不高的。网络教育与自考的统考…

《Java并发编程的艺术》之synchronized的底层实现原理

在学习锁优化时&#xff0c;对象头(Mark Word) 是必不可缺的一环&#xff0c;因为synchronized 用的锁是存在对象头里的。32位的虚拟机上对象头占64位&#xff08;8字节&#xff09;&#xff0c;64位的虚拟机上对象头占128位(16字节&#xff09;[^objectHead]&#xff1b;而不同…

[html] 你有使用过del标签吗?说说它的用途

[html] 你有使用过del标签吗&#xff1f;说说它的用途 这个del标签的话它的作用是在内容文本中间加一道横线 我之前有做过一个电商重构的页面 在标价部分 原价跟现价那块用过 因为促销 原价已经不起作用 所以需要用del标签包裹个人简介 我是歌谣&#xff0c;欢迎和大家一起交…

SQL 2005: @@identity 的妙用

insert into a values(aaaaa) print identity; //打印刚生成的主键值.**update a set cAAAAAAAAAAAA where b15print identity;转载于:https://www.cnblogs.com/MySpace/archive/2009/11/10/1599797.html