当前位置: 首页 > news >正文

OJ在线评测系统 后端基础部分开发 完善CRUD相关接口

完善相关接口

判斷编程语言是否合法

先从用户的请求拿到Language

package com.dduo.dduoj.service.impl;import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.dduo.dduoj.common.ErrorCode;
import com.dduo.dduoj.exception.BusinessException;
import com.dduo.dduoj.model.dto.questionsubmit.JudgeInfo;
import com.dduo.dduoj.model.dto.questionsubmit.QuestionSubmitAddRequest;
import com.dduo.dduoj.model.enums.QuestionSubmitLanguageEnum;
import com.dduo.dduoj.model.enums.QuestionSubmitStatusEnum;
import com.dduo.dduoj.service.mapper.QuestionSubmitMapper;
import com.dduo.dduoj.service.mapper.entity.Question;
import com.dduo.dduoj.service.mapper.entity.QuestionSubmit;
import com.dduo.dduoj.service.mapper.entity.User;
import com.dduo.dduoj.service.QuestionService;
import com.dduo.dduoj.service.QuestionSubmitService;
import javax.annotation.Resource;
import org.springframework.aop.framework.AopContext;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;/*** 提交题目服务实现**/
@Service
public class QuestionSubmitServiceImpl extends ServiceImpl<QuestionSubmitMapper, QuestionSubmit>implements QuestionSubmitService {@Resourceprivate QuestionService questionService;/*** 提交题目** @param questionSubmitAddRequest* @param loginUser* @return*/@Overridepublic long doQuestionSubmit(QuestionSubmitAddRequest questionSubmitAddRequest, User loginUser) {// 编程语言是否合法String language = questionSubmitAddRequest.getLanguage();QuestionSubmitLanguageEnum enumByValue = QuestionSubmitLanguageEnum.getEnumByValue(language);if (enumByValue==null){throw new BusinessException(ErrorCode.PARAMS_ERROR,"编程语言错误");}long questionId = questionSubmitAddRequest.getQuestionId();// 判断实体是否存在,根据类别获取实体Question question = questionService.getById(questionId);if (question == null) {throw new BusinessException(ErrorCode.NOT_FOUND_ERROR);}// 是否提交题目long userId = loginUser.getId();// 每个用户串行提交题目// 锁必须要包裹住事务方法QuestionSubmit questionSubmit = new QuestionSubmit();questionSubmit.setUserId(userId);questionSubmit.setQuestionId(questionId);questionSubmit.setCode(questionSubmitAddRequest.getCode());questionSubmit.setLanguage(language);//设置初始状态questionSubmit.setStatus(QuestionSubmitStatusEnum.WATING.getValue());questionSubmit.setJudgeInfo("{}");boolean save = this.save(questionSubmit);if(!save){throw new BusinessException(ErrorCode.SYSTEM_ERROR,"数据插入失败");}return questionSubmit.getId();}}

写好了 idea启动

代码运行成功

我们

使用接口文档提交题目试一试

数据库中数据录入成功

为了防止用户根据id爬取题目

建议把id的生成规则改成ASSIGN_ID

非连续递增

而不是从1开始递增

数值传到数据库中进行一个转换

/*** 创建** @param questionAddRequest* @param request* @return*/
@PostMapping("/add")
public BaseResponse<Long> addQuestion(@RequestBody QuestionAddRequest questionAddRequest, HttpServletRequest request) {if (questionAddRequest == null) {throw new BusinessException(ErrorCode.PARAMS_ERROR);}Question question = new Question();BeanUtils.copyProperties(questionAddRequest, question);List<String> tags = questionAddRequest.getTags();if (tags != null) {question.setTags(GSON.toJson(tags));}List<JudgeCase> judgeCase = questionAddRequest.getJudgeCase();if (judgeCase != null) {question.setJudgeCase(GSON.toJson(judgeCase));}List<JudgeConfig> judgeConfig = questionAddRequest.getJudgeConfig();if (judgeConfig != null) {question.setJudgeConfig(GSON.toJson(judgeConfig));}questionService.validQuestion(question, true);User loginUser = userService.getLoginUser(request);question.setUserId(loginUser.getId());question.setFavourNum(0);question.setThumbNum(0);boolean result = questionService.save(question);ThrowUtils.throwIf(!result, ErrorCode.OPERATION_ERROR);long newQuestionId = question.getId();return ResultUtils.success(newQuestionId);
}

@PostMapping("/update")
@AuthCheck(mustRole = UserConstant.ADMIN_ROLE)
public BaseResponse<Boolean> updateQuestion(@RequestBody QuestionUpdateRequest questionUpdateRequest) {if (questionUpdateRequest == null || questionUpdateRequest.getId() <= 0) {throw new BusinessException(ErrorCode.PARAMS_ERROR);}Question question = new Question();BeanUtils.copyProperties(questionUpdateRequest, question);List<String> tags = questionUpdateRequest.getTags();if (tags != null) {question.setTags(GSON.toJson(tags));}List<JudgeCase> judgeCase = questionUpdateRequest.getJudgeCase();if (judgeCase != null) {question.setJudgeCase(GSON.toJson(judgeCase));}List<JudgeConfig> judgeConfig = questionUpdateRequest.getJudgeConfig();if (judgeConfig != null) {question.setJudgeConfig(GSON.toJson(judgeConfig));}// 参数校验questionService.validQuestion(question, false);long id = questionUpdateRequest.getId();// 判断是否存在Question oldQuestion = questionService.getById(id);ThrowUtils.throwIf(oldQuestion == null, ErrorCode.NOT_FOUND_ERROR);boolean result = questionService.updateById(question);return ResultUtils.success(result);
}

@PostMapping("/edit")
public BaseResponse<Boolean> editQuestion(@RequestBody QuestionEditRequest questionEditRequest, HttpServletRequest request) {if (questionEditRequest == null || questionEditRequest.getId() <= 0) {throw new BusinessException(ErrorCode.PARAMS_ERROR);}Question question = new Question();BeanUtils.copyProperties(questionEditRequest, question);List<String> tags = questionEditRequest.getTags();if (tags != null) {question.setTags(GSON.toJson(tags));}List<JudgeCase> judgeCase = questionEditRequest.getJudgeCase();if (judgeCase != null) {question.setJudgeCase(GSON.toJson(judgeCase));}List<JudgeConfig> judgeConfig = questionEditRequest.getJudgeConfig();if (judgeConfig != null) {question.setJudgeConfig(GSON.toJson(judgeConfig));}// 参数校验questionService.validQuestion(question, false);User loginUser = userService.getLoginUser(request);long id = questionEditRequest.getId();// 判断是否存在Question oldQuestion = questionService.getById(id);ThrowUtils.throwIf(oldQuestion == null, ErrorCode.NOT_FOUND_ERROR);// 仅本人或管理员可编辑if (!oldQuestion.getUserId().equals(loginUser.getId()) && !userService.isAdmin(loginUser)) {throw new BusinessException(ErrorCode.NO_AUTH_ERROR);}boolean result = questionService.updateById(question);return ResultUtils.success(result);
}

枯燥的测试

完善

查询提交信息

接口功能 能够根据用户id 题目id 编程语言 去查询提交记录

注意事项 仅本人和管理员能看见自己提交代码的答案 提交代码

实现方案 先查询

package com.dduo.dduoj.model.dto.questionsubmit;import com.baomidou.mybatisplus.annotation.TableField;
import lombok.Data;import java.io.Serializable;//查询请求
@Data
public class QuestionSubmitQueryRequest implements Serializable {/*** 编程语言*/private String language;    /*** 提交状态*/private Integer status;/*** 题目id*/private Long questionId;/*** 用户id*/private Long userId;@TableField(exist = false)private static final long serialVersionUID = 1L;
}

QuestionSubmitVO

/*** 包装类转对象** @param questionSubmitVO* @return*/
public static QuestionSubmit voToObj(QuestionSubmitVO questionSubmitVO) {if (questionSubmitVO == null) {return null;}QuestionSubmit questionSubmit = new QuestionSubmit();BeanUtils.copyProperties(questionSubmitVO, questionSubmit);JudgeInfo judgeInfoObj = questionSubmitVO.getJudgeInfo();if (judgeInfoObj != null) {questionSubmit.setJudgeInfo(JSONUtil.toJsonStr(judgeInfoObj));}return questionSubmit;
}/*** 对象转包装类** @param questionSubmit* @return*/
public static QuestionSubmitVO objToVo(QuestionSubmit questionSubmit) {if (questionSubmit == null) {return null;}QuestionSubmitVO questionSubmitVO = new QuestionSubmitVO();BeanUtils.copyProperties(questionSubmit, questionSubmitVO);String judgeInfoStr = questionSubmit.getJudgeInfo();questionSubmitVO.setJudgeInfo(JSONUtil.toBean(judgeInfoStr, JudgeInfo.class));return questionSubmitVO;
}

先查询再根据权限去脱敏

/*** 分页获取题目提交(除了管理员外 普通用户是能看见非答案 提交代码等非公开信息)** @param questionSubmitQueryRequest* @return*/
@PostMapping("/list/page")
@AuthCheck(mustRole = UserConstant.ADMIN_ROLE)
public BaseResponse<Page<QuestionSubmitVO>> listQuestionSubmitByPage(@RequestBody QuestionSubmitQueryRequest questionSubmitQueryRequest,HttpServletRequest request) {long current = questionSubmitQueryRequest.getCurrent();long size = questionSubmitQueryRequest.getPageSize();//从数据库中获取信息Page<QuestionSubmit> questionSubmitPage = questionSubmitService.page(new Page<>(current, size),questionSubmitService.getQueryWrapper(questionSubmitQueryRequest));//返回脱敏方法return ResultUtils.success(questionSubmitService.getQuestionSubmitVOPage(questionSubmitPage,request));
}

脱敏处理

/*
* 单条数据
* */
@Override
public QuestionSubmitVO getQuestionSubmitVO(QuestionSubmit questionSubmit, User loginUser) {QuestionSubmitVO questionSubmitVO = QuestionSubmitVO.objToVo(questionSubmit);// 脱敏:仅本人和管理员能看见自己(提交 userId 和登录用户 id 不同)提交的代码long userId = loginUser.getId();// 处理脱敏if (userId != questionSubmit.getUserId() && !userService.isAdmin(loginUser)) {questionSubmitVO.setCode(null);}return questionSubmitVO;
}/** 多条数据* */
@Override
public Page<QuestionSubmitVO> getQuestionSubmitVOPage(Page<QuestionSubmit> questionSubmitPage, User loginUser) {List<QuestionSubmit> questionSubmitList = questionSubmitPage.getRecords();Page<QuestionSubmitVO> questionSubmitVOPage = new Page<>(questionSubmitPage.getCurrent(), questionSubmitPage.getSize(), questionSubmitPage.getTotal());if (CollectionUtils.isEmpty(questionSubmitList)) {return questionSubmitVOPage;}List<QuestionSubmitVO> questionSubmitVOList = questionSubmitList.stream().map(questionSubmit -> getQuestionSubmitVO(questionSubmit, loginUser)).collect(Collectors.toList());questionSubmitVOPage.setRecords(questionSubmitVOList);return questionSubmitVOPage;
}

QuestionSubmitServiceImpl

package com.dduo.dduoj.service.impl;import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.dduo.dduoj.common.ErrorCode;
import com.dduo.dduoj.constant.CommonConstant;
import com.dduo.dduoj.exception.BusinessException;
import com.dduo.dduoj.judge.JudgeService;
import com.dduo.dduoj.model.dto.questionsubmit.QuestionSubmitAddRequest;
import com.dduo.dduoj.model.dto.questionsubmit.QuestionSubmitQueryRequest;
import com.dduo.dduoj.model.entity.Question;
import com.dduo.dduoj.model.entity.QuestionSubmit;
import com.dduo.dduoj.model.entity.User;
import com.dduo.dduoj.model.enums.QuestionSubmitLanguageEnum;
import com.dduo.dduoj.model.enums.QuestionSubmitStatusEnum;
import com.dduo.dduoj.mapper.QuestionSubmitMapper;
import com.dduo.dduoj.model.vo.QuestionSubmitVO;
import com.dduo.dduoj.service.QuestionService;
import com.dduo.dduoj.service.QuestionSubmitService;
import javax.annotation.Resource;import com.dduo.dduoj.service.UserService;
import com.dduo.dduoj.utils.SqlUtils;
import org.apache.commons.collections4.CollectionUtils;
import org.apache.commons.lang3.ObjectUtils;
import org.apache.commons.lang3.StringUtils;
import org.springframework.context.annotation.Lazy;
import org.springframework.stereotype.Service;import java.util.List;
import java.util.concurrent.CompletableFuture;
import java.util.stream.Collectors;/*** 提交题目服务实现**/
@Service
public class QuestionSubmitServiceImpl extends ServiceImpl<QuestionSubmitMapper, QuestionSubmit>implements QuestionSubmitService {@Resourceprivate QuestionService questionService;@Resourceprivate UserService userService;@Resource@Lazyprivate JudgeService judgeService;/*** 提交题目** @param questionSubmitAddRequest* @param loginUser* @return*/@Overridepublic long doQuestionSubmit(QuestionSubmitAddRequest questionSubmitAddRequest, User loginUser) {// 校验编程语言是否合法String language = questionSubmitAddRequest.getLanguage();QuestionSubmitLanguageEnum languageEnum = QuestionSubmitLanguageEnum.getEnumByValue(language);if (languageEnum == null) {throw new BusinessException(ErrorCode.PARAMS_ERROR, "编程语言错误");}long questionId = questionSubmitAddRequest.getQuestionId();// 判断实体是否存在,根据类别获取实体Question question = questionService.getById(questionId);if (question == null) {throw new BusinessException(ErrorCode.NOT_FOUND_ERROR);}// 是否已提交题目long userId = loginUser.getId();// 每个用户串行提交题目QuestionSubmit questionSubmit = new QuestionSubmit();questionSubmit.setUserId(userId);questionSubmit.setQuestionId(questionId);questionSubmit.setCode(questionSubmitAddRequest.getCode());questionSubmit.setLanguage(language);// 设置初始状态questionSubmit.setStatus(QuestionSubmitStatusEnum.WAITING.getValue());questionSubmit.setJudgeInfo("{}");boolean save = this.save(questionSubmit);if (!save){throw new BusinessException(ErrorCode.SYSTEM_ERROR, "数据插入失败");}Long questionSubmitId = questionSubmit.getId();// 执行判题服务CompletableFuture.runAsync(() -> {judgeService.doJudge(questionSubmitId);});return questionSubmitId;}/*** 获取查询包装类(用户根据哪些字段查询,根据前端传来的请求对象,得到 mybatis 框架支持的查询 QueryWrapper 类)** @param questionSubmitQueryRequest* @return*/@Overridepublic QueryWrapper<QuestionSubmit> getQueryWrapper(QuestionSubmitQueryRequest questionSubmitQueryRequest) {QueryWrapper<QuestionSubmit> queryWrapper = new QueryWrapper<>();if (questionSubmitQueryRequest == null) {return queryWrapper;}String language = questionSubmitQueryRequest.getLanguage();Integer status = questionSubmitQueryRequest.getStatus();Long questionId = questionSubmitQueryRequest.getQuestionId();Long userId = questionSubmitQueryRequest.getUserId();String sortField = questionSubmitQueryRequest.getSortField();String sortOrder = questionSubmitQueryRequest.getSortOrder();// 拼接查询条件queryWrapper.eq(StringUtils.isNotBlank(language), "language", language);queryWrapper.eq(ObjectUtils.isNotEmpty(userId), "userId", userId);queryWrapper.eq(ObjectUtils.isNotEmpty(questionId), "questionId", questionId);queryWrapper.eq(QuestionSubmitStatusEnum.getEnumByValue(status) != null, "status", status);queryWrapper.eq("isDelete", false);queryWrapper.orderBy(SqlUtils.validSortField(sortField), sortOrder.equals(CommonConstant.SORT_ORDER_ASC),sortField);return queryWrapper;}/** 单条数据* */@Overridepublic QuestionSubmitVO getQuestionSubmitVO(QuestionSubmit questionSubmit, User loginUser) {QuestionSubmitVO questionSubmitVO = QuestionSubmitVO.objToVo(questionSubmit);// 脱敏:仅本人和管理员能看见自己(提交 userId 和登录用户 id 不同)提交的代码long userId = loginUser.getId();// 处理脱敏if (userId != questionSubmit.getUserId() && !userService.isAdmin(loginUser)) {questionSubmitVO.setCode(null);}return questionSubmitVO;}/** 多条数据* */@Overridepublic Page<QuestionSubmitVO> getQuestionSubmitVOPage(Page<QuestionSubmit> questionSubmitPage, User loginUser) {List<QuestionSubmit> questionSubmitList = questionSubmitPage.getRecords();Page<QuestionSubmitVO> questionSubmitVOPage = new Page<>(questionSubmitPage.getCurrent(), questionSubmitPage.getSize(), questionSubmitPage.getTotal());if (CollectionUtils.isEmpty(questionSubmitList)) {return questionSubmitVOPage;}List<QuestionSubmitVO> questionSubmitVOList = questionSubmitList.stream().map(questionSubmit -> getQuestionSubmitVO(questionSubmit, loginUser)).collect(Collectors.toList());questionSubmitVOPage.setRecords(questionSubmitVOList);return questionSubmitVOPage;}}

controller层代码

/*** 提交题目** @param questionSubmitAddRequest* @param request* @return 提交记录的 id*/
@PostMapping("/")
public BaseResponse<Long> doQuestionSubmit(@RequestBody QuestionSubmitAddRequest questionSubmitAddRequest,HttpServletRequest request) {if (questionSubmitAddRequest == null || questionSubmitAddRequest.getQuestionId() <= 0) {throw new BusinessException(ErrorCode.PARAMS_ERROR);}// 登录才能点赞final User loginUser = userService.getLoginUser(request);long questionSubmitId = questionSubmitService.doQuestionSubmit(questionSubmitAddRequest, loginUser);return ResultUtils.success(questionSubmitId);
}

listQuestionSubmitByPage

/*** 分页获取题目提交(除了管理员外 普通用户是能看见非答案 提交代码等非公开信息)** @param questionSubmitQueryRequest* @return*/
@PostMapping("/list/page")
@AuthCheck(mustRole = UserConstant.ADMIN_ROLE)
public BaseResponse<Page<QuestionSubmitVO>> listQuestionSubmitByPage(@RequestBody QuestionSubmitQueryRequest questionSubmitQueryRequest, HttpServletRequest request) {long current = questionSubmitQueryRequest.getCurrent();long size = questionSubmitQueryRequest.getPageSize();//从数据库中获取信息Page<QuestionSubmit> questionSubmitPage = questionSubmitService.page(new Page<>(current, size),questionSubmitService.getQueryWrapper(questionSubmitQueryRequest));final User loginUser = userService.getLoginUser(request);//返回脱敏方法return ResultUtils.success(questionSubmitService.getQuestionSubmitVOPage(questionSubmitPage, loginUser));
}

相关文章:

OJ在线评测系统 后端基础部分开发 完善CRUD相关接口

完善相关接口 判斷编程语言是否合法 先从用户的请求拿到Language package com.dduo.dduoj.service.impl;import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper; import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl; import com.dduo.dduoj…...

计算机网络--TCP、UDP抓包分析实验

计算机网络实验 目录 实验目的 实验环境 实验原理 1、UDP协议 2、TCP协议 实验具体步骤 实验目的 1、掌握使用wireshark工具对UDP协议进行抓包分析的方法&#xff0c;掌握UDP协议的报文格式&#xff0c;掌握UDP协议校验和的计算方法&#xff0c;理解UDP协议的优缺点&am…...

FreeRTOS的中断管理

前言 FreeRTOS的任务有优先级&#xff0c;MCU的硬件中断有中断优先级&#xff0c;这是两个不同的概念&#xff0c;FreeRTOS的任务管理要用到硬件中断&#xff0c;使用FreeRTOS时候也可以使用硬件中断&#xff0c;但是硬件中断ISR的设计要注意一些设计原则&#xff0c;在本节中我…...

JS加密=JS混淆?(JS加密、JS混淆,是一回事吗?)

JS加密、JS混淆&#xff0c;是一回事吗&#xff1f; 是的&#xff01;在国内&#xff0c;JS加密&#xff0c;其实就是指JS混淆。 1、当人们提起JS加密时&#xff0c;通常是指对JS代码进行混淆加密处理&#xff0c;而不是指JS加密算法&#xff08;如xor加密算法、md5加密算法、…...

hive-拉链表

目录 拉链表概述缓慢变化维拉链表定义 拉链表的实现常规拉链表历史数据每日新增数据历史数据与新增数据的合并 分区拉链表 拉链表概述 缓慢变化维 通常我们用一张维度表来维护维度信息&#xff0c;比如用户手机号码信息。然而随着时间的变化&#xff0c;某些用户信息会发生改…...

高并发内存池(六):补充内容

目录 有关大于256KB内存的申请和释放处理方法 处理大于256KB的内存申请 补充内容1 补充内容2 补充内容3 处理大于256KB的内存释放 新增内容1 新增内容2 测试函数 使用定长内存池替代new 释放对象时不传对象大小 补充内容1 补充内容2 补充内容3 补充内容4 测试…...

高性能存储 SIG 月度动态:优化 fuse 提升 AI 存储接入能力,erofs 工具发布新版本

本次月报综合了 SIG 在 7、8 两个月的工作进展&#xff0c;包含多项新特性、优化、Bugfix 等。 SIG 整体进展 fuse 支持 failover&#xff0c;并优化 background 读写公平性&#xff0c;提升 AI 存储接入场景的能力。 erofs page cache 共享特性已发到上游社区&#xff0c;re…...

2024 年最新 Protobuf 结构化数据序列化和反序列化详细教程

Protobuf 序列化概述 Protobuf&#xff08;Protocol Buffers&#xff09;是由Google开发的一种语言中立、平台中立、可扩展的序列化结构数据的方法。它用于在不同系统之间高效地交换数据。Protobuf使用定义文件&#xff08;.proto&#xff09;来描述数据结构&#xff0c;并通过…...

【小程序】微信小程序课程 -4 项目实战

目录 1、 效果图 2、创建项目 2.1 创建小程序端 2.1.1 先创建纯净项目 2.1.2 删除components 2.1.4 删除app.json红色部分 2.1.5 删除index.json红色部分 2.1.6 删除index.wxss全部内容 2.1.7 删除index.wxml全部内容 2.1.8 app.json创建4个页面 2.1.9 app.json添加…...

【期刊】论文索引库-SCI\SSCI\IE\南大核心\北大核心\CSCD等

外文期刊检索 SCI SCI即《科学引文索引》(Science Citation Index),是由美国科学信息研究所(Institute for Scientific Information)创建于1961年,收录文献的作者、题目、源期刊、摘要、关键词,不仅可以从文献引证的角度评估文章的学术价值,还可以迅速方便地组建研究课…...

开源链动 2+1 模式 S2B2C 商城小程序:社交电商团队为王的新引擎

摘要&#xff1a;本文深入探讨在社交电商领域中&#xff0c;团队的重要性以及如何借助开源链动 21 模式 S2B2C 商城小程序&#xff0c;打造具有强大竞争力的团队&#xff0c;实现个人价值与影响力的放大&#xff0c;创造被动收入&#xff0c;迈向财富自由之路&#xff0c;同时为…...

使用Fiddler Classic抓包工具批量下载音频资料

1. 通过F12开发者工具&#xff0c;下载音频文件 浏览器打开音频列表->F12快捷键->网络->媒体&#xff0c;播放一个音频文件&#xff0c;右边媒体下生成一个音频文件&#xff0c;右击“在新标签页中打开”&#xff0c;可以下载这个音频文件。 2.通过Fiddler Classic抓…...

QT开发:基于Qt实现的交通信号灯模拟器:实现一个带有倒计时功能的图形界面应用

介绍 本文将介绍如何使用Qt框架实现一个简单的交通信号灯控制程序。本程序包括一个图形界面&#xff0c;显示红、黄、绿三色信号灯&#xff0c;并通过定时器控制信号灯的切换。同时&#xff0c;我们还将实现一个带有按钮的界面&#xff0c;用于展示信号灯的状态。 1. 安装Qt开…...

【编程基础知识】网络I/O模型详解:从阻塞到异步

引言 网络I/O模型是网络编程的核心&#xff0c;它们决定了应用程序如何进行读写操作以与网络进行数据交换。了解不同的网络I/O模型对于设计高效、可扩展的网络应用程序至关重要。 一、阻塞I/O&#xff08;Blocking I/O&#xff09; 1. 定义 阻塞调用&#xff1a;当应用程序…...

yolo自动化项目实例解析(六)自建UI(主窗口、预览窗口)

前面我们大致把各个代码块梳理出来了&#xff0c;但是还是不知道从那块开始&#xff0c;我们这里主要先通过ui页面的元素去推理整个执行过程&#xff0c;我们首先需要知道ui功能里面有那些组件 qt设计师基础控件 Qt Designer 是一个图形界面设计工具&#xff0c;用于创建 Qt 应…...

Unity优质教程分类汇总 【持续更新中】

以下收录的均为作者自己看过的觉得比较好的教程 基础 Unity入门&#xff1a; https://www.bilibili.com/video/BV1HX4y1V71E?p13 生命周期 https://docs.unity.cn/cn/2022.3/uploads/Main/monobehaviour_flowchart.svg https://zhuanlan.zhihu.com/p/551294000 编程技巧…...

真正掌握left join on 和 where 的差别

总结 用 where 是先连接然后再筛选用 on 是先筛选再连接数据库在通过连接两张或多张表来返回记录时&#xff0c;都会生成一张中间的临时表&#xff0c;然后再将这张临时表返回给用户。在使用left jion时&#xff0c;on和where条件的区别如下&#xff1a; on条件是在生成临时表…...

神经网络在多分类问题中的应用

作者简介:热爱数据分析,学习Python、Stata、SPSS等统计语言的小高同学~个人主页:小高要坚强的博客当前专栏:Python之机器学习本文内容:神经网络在多分类问题中的应用作者“三要”格言:要坚强、要努力、要学习 目录 1. 引言 2.数据构造 3.划分数据集 4.神经网络实现多…...

nginx的安装和使用

源码安装 1.环境准备&#xff1a;卸载其他方式安装的web应用&#xff0c;防止端口冲突 2.下载nginx源码包 wget https://nginx.org/download/nginx-1.20.2.tar.gz 3.源码编译安装 yum install -y gcc pcre-devel zlib-devel #安装依赖包 useradd -M -s /sbin/nologin ngi…...

js采用覆盖键、覆盖鼠标滑动事件实现禁止网页通过 ctrl + +/- 和 ctrl + 滚轮 对页面进行缩放

一、兼容电脑端的禁止通过 ctrl /- 和 ctrl 滚轮 对页面进行缩放 const keyCodeMap {// 91: true, // command61: true,107: true, // 数字键盘 109: true, // 数字键盘 -173: true, // 火狐 - 号187: true, // 189: true, // -};二、覆盖ctrl||command ‘’/‘-’ // 覆…...

【kafka】Golang实现分布式Masscan任务调度系统

要求&#xff1a; 输出两个程序&#xff0c;一个命令行程序&#xff08;命令行参数用flag&#xff09;和一个服务端程序。 命令行程序支持通过命令行参数配置下发IP或IP段、端口、扫描带宽&#xff0c;然后将消息推送到kafka里面。 服务端程序&#xff1a; 从kafka消费者接收…...

3.3.1_1 检错编码(奇偶校验码)

从这节课开始&#xff0c;我们会探讨数据链路层的差错控制功能&#xff0c;差错控制功能的主要目标是要发现并且解决一个帧内部的位错误&#xff0c;我们需要使用特殊的编码技术去发现帧内部的位错误&#xff0c;当我们发现位错误之后&#xff0c;通常来说有两种解决方案。第一…...

【ROS】Nav2源码之nav2_behavior_tree-行为树节点列表

1、行为树节点分类 在 Nav2(Navigation2)的行为树框架中,行为树节点插件按照功能分为 Action(动作节点)、Condition(条件节点)、Control(控制节点) 和 Decorator(装饰节点) 四类。 1.1 动作节点 Action 执行具体的机器人操作或任务,直接与硬件、传感器或外部系统…...

Robots.txt 文件

什么是robots.txt&#xff1f; robots.txt 是一个位于网站根目录下的文本文件&#xff08;如&#xff1a;https://example.com/robots.txt&#xff09;&#xff0c;它用于指导网络爬虫&#xff08;如搜索引擎的蜘蛛程序&#xff09;如何抓取该网站的内容。这个文件遵循 Robots…...

【Java_EE】Spring MVC

目录 Spring Web MVC ​编辑注解 RestController RequestMapping RequestParam RequestParam RequestBody PathVariable RequestPart 参数传递 注意事项 ​编辑参数重命名 RequestParam ​编辑​编辑传递集合 RequestParam 传递JSON数据 ​编辑RequestBody ​…...

Rapidio门铃消息FIFO溢出机制

关于RapidIO门铃消息FIFO的溢出机制及其与中断抖动的关系&#xff0c;以下是深入解析&#xff1a; 门铃FIFO溢出的本质 在RapidIO系统中&#xff0c;门铃消息FIFO是硬件控制器内部的缓冲区&#xff0c;用于临时存储接收到的门铃消息&#xff08;Doorbell Message&#xff09;。…...

在Ubuntu24上采用Wine打开SourceInsight

1. 安装wine sudo apt install wine 2. 安装32位库支持,SourceInsight是32位程序 sudo dpkg --add-architecture i386 sudo apt update sudo apt install wine32:i386 3. 验证安装 wine --version 4. 安装必要的字体和库(解决显示问题) sudo apt install fonts-wqy…...

嵌入式学习笔记DAY33(网络编程——TCP)

一、网络架构 C/S &#xff08;client/server 客户端/服务器&#xff09;&#xff1a;由客户端和服务器端两个部分组成。客户端通常是用户使用的应用程序&#xff0c;负责提供用户界面和交互逻辑 &#xff0c;接收用户输入&#xff0c;向服务器发送请求&#xff0c;并展示服务…...

【笔记】WSL 中 Rust 安装与测试完整记录

#工作记录 WSL 中 Rust 安装与测试完整记录 1. 运行环境 系统&#xff1a;Ubuntu 24.04 LTS (WSL2)架构&#xff1a;x86_64 (GNU/Linux)Rust 版本&#xff1a;rustc 1.87.0 (2025-05-09)Cargo 版本&#xff1a;cargo 1.87.0 (2025-05-06) 2. 安装 Rust 2.1 使用 Rust 官方安…...

Linux nano命令的基本使用

参考资料 GNU nanoを使いこなすnano基础 目录 一. 简介二. 文件打开2.1 普通方式打开文件2.2 只读方式打开文件 三. 文件查看3.1 打开文件时&#xff0c;显示行号3.2 翻页查看 四. 文件编辑4.1 Ctrl K 复制 和 Ctrl U 粘贴4.2 Alt/Esc U 撤回 五. 文件保存与退出5.1 Ctrl …...