What is Apache Spark? Disrupting Hadoop’s Big Data Platform_cxw9087’s Blog

Apache Spark Definition Apache Spark is a data processing framework that can quickly perform processing tasks on very large data sets, and can also Other distributed computing tools work together to distribute data processing tasks among multiple computers. These two qualities are key to the fields of big data and machine learning, which require the marshalling of vast computing power to process large data stores. Spark also eases the burden on developers with an easy-to-use API that relieves some of the programming burden for these tasks. API simplifies the heavy lifting of distributed computing and big data processing. Apache Spark has become the key big data distributed processing system in the world since its establishment in UC Berkeley’s AMPLab in 2009 one of the frames. Spark can be deployed in a variety of ways, provides native bindings for the Java, Scala, Python, and R programming languages, and supports SQL, streaming data, machine learning, and graph processing. You’ll find it used by banks, telcos, gaming companies, governments, and all the major tech giants like Apple, Facebook, IBM, and Microsoft. [ InfoWorld’s Technology of the Year 2020 Award Winner: Best Software Development, Cloud Computing, Data Analytics and Machine Learning Product of the…

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Basic collocation of webpack (Vue + Element)

class=”markdown_views prism-tomorrow-night”> webpack front-end project construction tool 1. Current difficulties facing web development Complicated file dependencies Static resource request is inefficient Modular support is not friendly Browser compatibility with advanced Javascript features is low etc… 2. webpackOverview webpack is a popular front-end project building tool (packaging tool), which can solve the dilemma faced by current web development. webpack provides friendly modular support, as well as powerful functions such as code compression and obfuscation, handling js compatibility issues, and performance optimization. This allows programmers to focus on the implementation of specific functions, improving development efficiency and project maintainability. At present, the front-end projects in most enterprises are packaged and built based on webpack. 3. Basic usage of webpack: 3.1 Create a list of interlaced color-changing items Create a new project blank directory, and run the npm init –y command to initialize the package management configuration file package.json Create a new src source code directory Create a new src-> index.html home page – index.js file Initialize the basic structure of the homepage Run npm install jquery –S command to install jQuery Achieve the interlaced color changing effect of the list in a modular form index.html Temporarily introduce: script src=”./index.js”</ script ul liThis…

Overview of Java Backend Technology_weixin_33719619’s blog

What skills does a qualified Java back-end engineer need to master? Scan the QR code below to see Java backend technology overview Figure. Core principles of software development Here are some core principles that software development should follow: Don’t Repeat Yourself: This is a basic principle of software development, that is, don’t do repetitive work. It is also a kind of what is now called “geek culture”. Duplication of code and duplication of work are unreasonable in software development. Eliminating these duplications by various means is a core working principle of software development. Keep it simple stupid: the KISS principle. In the work of software design, in many cases, don’t think too complicated, and don’t over-design and optimize prematurely. Using the simplest and effective solution will avoid various additional costs brought by complex solutions. It is not only conducive to subsequent maintenance, but also conducive to further expansion. You Ain’t Gonna Need It: That is the YAGNI principle. Just include the functionality that your application needs, and don’t try to add anything else you think you might need. Because in a software, 80% of the requests are often spent on 20% of the functions. Done is better than perfect: When…

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Win10: ‘javac’ is not recognized as an internal or external command, operable program or batch file. _win10 javac file

class=”markdown_views prism-atom-one-dark”> In order to solve it, configure JAVA_HOME, CLASSPATH, and Path environment variables (if not configured, you can search for “Java environment configuration” to configure). Problem still occurs: ‘javac’ is not recognized as an internal or external command, operable program or batch file. After configuring the environment variables, there will be omissions for the Path environment variable. For example, the Path environment variable created by ① in the above picture , and ② is automatically created by the system, you need to put ① on ②.

Principles of Design Patterns – tnt32’s Blog

Design Pattern Principles 1. Single Responsibility Principle: It is best for a class to have only one variation factor, so that the code reuse rate can be maximized. 2. Open and closed principle: open to expand, closed to code modification. 3. Dependency inversion principle: Interface-oriented programming, not implementation-oriented programming. 4. Dimiter’s Law: Minimize the interaction between system classes and reduce the degree of coupling between classes . 5. Interface isolation principle: The definition of the interface should be specific, the less the better. 6. Principle of synthetic aggregation and reuse: encapsulating existing objects in a new object can reduce the degree of coupling between them . Principles of object-oriented design OO, we are doing object-oriented program development every day, are we really OO? What are the principles of OO? SRP:Single Responsibility Principle As far as a class is concerned, there should be only one reason for it to change OCP: Open-Closed Principle Software entities (classes, modules, functions, etc.) should be extensible but not modifiable LSP: Listov Substitution Principle Subtypes must be able to replace their base type DOP: Dependency Inversion Principle Abstractions should not depend on details, details should depend on abstractions ISP: Interface Segregation Principle Clients should not be…

Qt4 error LNK2019 unresolved external symbol solution_How can I be romantic again Blog

Delete the build-(project name)-Debug folder under the parent directory where the current qt project is located Reprint linkhttps://blog .csdn.net/ygzhong000/article/details/44843371https://blog.csdn.net/ygzhong000/article/details/44843371

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Tomcat installation & download & uninstall & solve console garbled & modify default port_CodeWang_NC’s blog

class=”markdown_views prism-atom-one-light”> Introduction Refer to the video tutorial:https://www.bilibili.com/video/BV1Qf4y1T7Hx?p=88 tomcat download tomcat installation Tomcat server startup and shutdown tomcat uninstall Tomcat console garbled problem Modify the default port of tomcat 1.tomcat download 1.1 Download the latest version Official website: https://tomcat.apache.org/ Find download—>Recommend to download tomcat8 version The latest is 8.5.78, click the corresponding version to download 1.2. Historical version tomcat download: Method 1: URL: https://archive.apache.org/dist/tomcat/tomcat-8 // Method 2: Or click Archivers on the download interface of the official website, enter the page and click the corresponding version For example: v8.5.178—>bin/—>click suitable Download your own 2.tomcat installation 2.1.Tomcat is a green version, just decompress it Note, when Tomcat decompresses, the directory where the decompression is located can be arbitrary, but it is best to decompress to a directory that does not contain Chinese and spaces, because when deploying the project later, if the path Chinese characters or spaces may cause program deployment to fail. 3. Tomcat server opening and closing (window system bat, linux system sh) 3.1 bin—->startup.bat (double click) 3.2 Close the server (three methods) Directly × drop the running window: force close bin/—>shutdown.bat: normal shutdown Ctrl+C on the console interface: normal shutdown 4. Tomcat uninstall (Delete the tomcat directory directly)…

Correct use of the rich text editor wangeditor in vue and the pitfalls encountered when using wangeditor_chengxue_123’s blog

Correct use of the rich text editor wangeditor in vue and the pitfalls encountered when using wangeditor_chengxue_123’s blog

Address: http://www.wangeditor.com/, gitHub:https://github.com /wangfupeng1988/wangEditor/blob/master/example/demo/in-vue/src/components/Editor.vue 1) First install npm i wangeditor in the terminal 2) Import a rich text editor import E from “wangeditor” 3) In the past, when using it like this, it will not report an error, but now it does not work. When I suspect that the wangeditor has been updated and revised, some content of the downloaded package is different, resulting in the following error 4) If you change the level, I debug in the browser, you can use css to change // /deep/.w-e-toolbar { // z-index: 100 !important; // } // /deep/.w-e-text-container { // z-index: 100 !important; // } 5) Of course, if you don’t need to change it with CSS, you need to change it in the level and content var editor = new E(this.$refs.editor); // cannot be used here console.log(editor); Found this editor Only after editor.config.onchange and editor.zIndex.baseZIndex can get the content and level, follow 1) 2) operation npm i wangeditor Introduce a rich text editor import E from “wangeditor” mounted() { var editor = new E(this.$refs.editor); // cannot be used here console. log(editor); // editor.customConfig.onchange = (html) => { // this.articalObj.content = html; // }; // editor.customConfig.zIndex = 100; //This can’t be used…

Ubuntu 16.04 gtx1060 graphics card installation [transfer]_weixin_33722405’s blog

This article is reproduced from: https://blog.csdn.net/u010925447/article/details/79754044

How to install studio-3t_luoganttcc’s blog under ubuntu

class=”markdown_views prism-atom-one-dark”> studio-3t download 3t is very easy to install under linux Convenient, just unzip directly! Run: open the terminal in the bin folder ./studio-3t.sh

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