Writing a Simple Publisher and Subscriber

用c++实现一个publisher/subscriber publisher #include "ros/ros.h" #include "std_msgs/String.h" #include <sstream> /** * This tutorial demonstrates simple sending of messages over the ROS system. */ int main(int argc, char **argv) { /**…

ROS学习手记 - 8 编写ROS的Publisher and Subscriber

上一节我们完成了 message & srv 文件的创建和加入编译,这次我们要玩简单的Publisher 和 Subscriber 要玩 Publisher 和 Subscriber, 需要具备的条件有哪些呢?先总结一下: 创建并生成自己的Package,本次是 beginner_tutorials 创建并生成ROS message & srv 详细版的手记要看我上传到百度文库的文件了:http://wenku.baidu.com/view/f872755a26fff705cc170ade…

Writing a simple Lexer in PHP/C++/Java

catalog . Comparison of parser generators . Writing a simple lexer in PHP . phc . JLexPHP: A PHP Lexer(xx.lex.php) Created By Java By x.lex File Input . JFlex . JLex: A Lexical Analyzer Generator for Java . PhpParser 0. Comparison of parser generator…

Publisher和Subscriber节点

一.Publisher节点 /*"ros/ros.h"里面包含了ROS系统内最常用的一些头文件,包含此文件,便可以使用ROS的核心功能.*/#include "ros/ros.h" /*"std_msgs/String"是由std_msgs包自动生成的头文件,定义了String信息类型,包含此文件,我们就可以使用String类型*/ #include "std_msgs/String.h" #include <sstre…

Writing a Simple Service and Client (C++)

此前说的publisher/subscriber都是广播式的,subscriber被动地接收消息,二者没有request/response这种交互. Service Node Client Node Service Node #include "ros/ros.h" #include "beginner_tutorials/AddTwoInts.h" //由.srv文件生成的头文件 //service函数.提供add功能,入参为srv文件里定义好的request/r…

C#的publisher与subscriber，事件发布者与订阅者

说明:示例借鉴自这里,但原版很不友好,于是修改了下,一目了然. 直接上代码: using System; using System.Collections.Generic; using System.IO; using System.Linq; using System.Text; using System.Threading.Tasks; namespace _21_event_事件 { /* * 事件(Event) 基本上说是一个用户操作,如按键.点击.鼠标移动等等,或者是一些出现,如系统生…

Writing a Simple YARN Application 从hadoop生态抽出yarn ，单独使用yarn

Apache Hadoop 2.9.1 – Hadoop: Writing YARN Applications https://hadoop.apache.org/docs/current/hadoop-yarn/hadoop-yarn-site/WritingYarnApplications.html…

ROS验证publisher和subscriber

在前面的两篇博客中我们用C++在ROS中创建了一个发布者和接收者,并使用catkin_make构建了新的节点,下面就需要验证一下,我们写的是否正确. 首先运行roscore roscore 在使用catkin之前,确保把workspace的setup.bash文件source一下,这个文件必须是你执行catkin_make之后生成的文件. # In your catkin workspace $ cd ~/catkin_ws $ source ./devel/setup.bash 打开一个新的终…

ROS教程

Learning ROS 学习ROS Depending on your learning style and preferences, you can take two approaches to learning ROS: 根据你的学习风格和喜好,你可以采取两种方法来学习ROS: Start the Tutorials - Dive in right away and start working with ROS. 一种是直接开始上手操作ROS (教程:http://wiki.ros.or…

Publisher/Subscriber(发布/订阅者)消息模式开发流程

该模式的作用是发布者和订阅者可以相互发送消息发布者和订阅者都充当生产者和消费者发布者 package publisher.to.subscriber; import java.awt.font.TextMeasurer; import javax.jms.Connection;import javax.jms.Destination; import javax.jms.JMSException;import javax.jms.MapMessage;import javax.jms.Me…

How to write simple HTTP proxy with Boost.Asio

How to write simple HTTP proxy with Boost.Asio How to write simple HTTP proxy with Boost.Asio Russian · English Меню: Main Functional programming Clojure Emacs Information Security C++ Open Source Projects Articles In this article I describe process…

Apache POI – Reading and Writing Excel file in Java

来源于:https://www.mkyong.com/java/apache-poi-reading-and-writing-excel-file-in-java/ In this article, we will discuss about how to read and write an excel file using Apache POI 1. Basic definitions for Apache POI library This section briefly describe a…

A Simple Makefile Tutorial

A Simple Makefile Tutorial A Simple Makefile Tutorial: http://www.cs.colby.edu/maxwell/courses/tutorials/maketutor/ Makefiles are a simple way to organize code compilation. This tutorial does not even scratch the surface of what is possible using mak…

writing a usb driver（在国外的网站上复制下来的）

Writing a Simple USB Driver From Issue #120April 2004 Apr 01, 2004 By Greg Kroah-Hartman in Software Give your Linux box a multicolored light you can see from across the room, and learn how to write a simple driver for the next piece of hardware…

Spock - Document -04- Interaction Based Testing

Interaction Based Testing Peter Niederwieser, The Spock Framework TeamVersion 1.1 Interaction-based testing is a design and testing technique that emerged in the Extreme Programming (XP) community in the early 2000’s. Focusing on the behavior of obje…

ROS actionlib学习（三）

下面这个例子将展示用actionlib来计算随机变量的均值和标准差.首先在action文件中定义goal.result和feedback的数据类型,其中goal为样本容量,result为均值和标准差,feedback为样本编号.当前样本数据.均值和标准差. #goal definition int32 samples --- #result definition float32 mean float32 std_dev --- #feedback int32 sample float32 dat…

nginx-rtmp-module--------------WIKI

https://github.com/arut/nginx-rtmp-module/wiki/Directives#idle_streams =============================================================== ================================================================= Core rtmp server listen application timeout ping…

[转]Design Pattern Interview Questions - Part 2

Interpeter , Iterator , Mediator , Memento and Observer design patterns. (I) what is Interpreter pattern? (B) Can you explain iterator pattern? (A) Can you explain mediator pattern? (I) Can you explain memento pattern? (B) Can you explain observer pa…

Architecture Pattern: Publish-subscribe Pattern

1. Brief 一直对Observer Pattern和Pub/Sub Pattern有所混淆,下面打算通过这两篇Blog来梳理这两种模式.若有纰漏请大家指正. 2. Role Publisher:消息发布者,组装原始消息实体并触发消息传递的主体. Subscriber:消息订阅者,接收消息实体并作出响应的主体. Message Broker or Event Bus:消息发布者与消息订阅者间的媒介,内含消息过滤和消息路由的功能,并可通过内置的消息队列(message queue)现实优…

How to build a GUI in ROS with Qt / C++

p { margin-bottom: 0.1in; direction: ltr; line-height: 120%; text-align: left; widows: 2; orphans: 2 } a:link { color: #0000ff } Overview A graphical user interface or GUI enables people especially end users to interactive with ROS through graphical…

Jmeter_初步认识随笔

1. 简介 Apache JMeter是100%纯java桌面应用程序,被设计用来测试客户端/服务器结构的软件(例如web应用程序).它可以用来测试包括基于静态和动态资源程序的性能,例如静态文件,Java Servlets,Java 对象,数据库,FTP 服务器等等.JMeter可以用来在一个服务器.网络或者对象上模拟重负载来测试它的强度或者分析在不同的负载类型下的全面性能. 另外,JMeter能够通过让你们用断言创建测试脚本来验证我们的应用程序是否返回了我们期望的结果,从而帮助我们回归测试我们…

DLNA介绍(包含UPnP，2011/6/20 更新)

这部分的内容大多来源于网络及官方文档,依照自己的翻译理解整理所成.东西比較多,从头慢慢看还是能够懂个大概的. 文件夹: 一.DNLA的建立二.DLNA的成员三.DLNA标准的制定四.DLNA的设备五.DLNA的架构六.云时代的数字家庭(待填坑) 扩展阅读I: UPnP的工作过程------------DLNA基础协议框架扩展阅读II UPnP AV(Audio/Video) Architecture---------------DLNA媒体应用框架) 一.DNLA的建立 DLNA 成…

Apache JMeter--网站自动测试与性能测评

Apache JMeter--网站自动测试与性能测评 2013-02-28 15:48:05 标签:Jmeter From:http://bdql.iteye.com/blog/291987 出于学习热情,翻译总结Emily H. Halili的<Apache JMeter>一书的部分内容. JMeter的简介可以肯定的是,JMeter至少符合以下几条自动测试标准: 零购置成本--直接从http://jakarta.apache.org/site/downloads/downloads_jm…

Reactive Programming

Reactive的表现 Reactive 规范是 JVM Reactive 扩展规范 Reactive Streams JVM,而 Reactive 实现框架则是最典型的实现: Reactive Streams /Java 9 一个非常底层的约定,提供了Publisher和Subscriber接口. Java 9 提供了Flow API 的支持 Spring Framework 5.0 / ReactorSpring 5,以 Reactive 为基础的Reactor框架 ,逐步构建一套完整的 R…

What can Reactive Streams offer EE4J?

https://developer.lightbend.com/blog/2018-02-06-reactive-streams-ee4j/index.html By James Roper (@jroper), February 6, 2018 In my current role at Lightbend I’m investigating and pursuing opportunities where Reactive Streams can make the lives of EE4J…

getting-started-with-mqtt

来自:https://dzone.com/refcardz/getting-started-with-mqtt SECTION 1 Why MQTT? The Internet of Things (IoT) has recently gained massive traction. IoT challenges enterprises, small companies, and developers with new problems to solve. While HTTP is the d…

5 Protocols For Event-Driven API Architectures

The internet is a system of communication, and as such, the relationship between client and server, as well as server to server, is one of the most oft-discussed and hotly contested concepts. event-driven architecture is a methodology of defining the…