shell script for big data learning

A learning process of cooking chicken and looking for a job preface I am a vegetable chicken looking for big data development post in the future After extensive online search for relevant work materials, it is not difficult to find that companies often need us to have the following skills: 1. Solid SQL foundation and proficient in Hive ...

Posted by RonDahl on Tue, 05 Apr 2022 22:25:38 +0300

The use and principle analysis of sort() method in JAVA

Arrays.sort and collections Analysis of sort implementation principle 1. Use sort sort() is a method used for sorting in Java. When we concentrate on learning various classical sorting algorithms, in fact, a sort() in the code can be solved, and the time complexity and space complexity will not be too high. In fact, sort() can sort not only ...

Posted by tabs on Mon, 04 Apr 2022 23:52:28 +0300

Singleton pattern of JAVA design pattern

1, Introduction to singleton mode 1 mode description Implement one class, only one instantiated object, and provide a global access point 2 role (problem solved) Ensure that there is only one object in a class to reduce the coupling between objects 3 working principle In Java, we operate these classes by using objects (after class ins ...

Posted by yuppicide on Mon, 04 Apr 2022 00:57:50 +0300

From simple to deep, 66 JavaScript interview knowledge points and answer analysis

1. Introduce the data types of js and how the values are stored For details, see my previous article: "front end package" may be the most thorough explanation of JavaScript data types There are 8 data types in JavaScript, including 7 basic data types: Undefined, Null, Boolean, Number, String, Symbol (es6 added, representing unique v ...

Posted by pedroteixeira07 on Sat, 02 Apr 2022 12:41:42 +0300

JS some common array syntax (ES5, ES6, ES7)

Some of Math's 1,Math.abs(x) Meaning: returns the absolute value of x Application scenario: make 0.1 + 0.2 = = 0.3 Method: set an error range value, which is usually called "machine precision". For Javascript, this value is usually 2 ^ - 52. In ES6, we have provided such an attribute: number Epsilon, and this value is exactly equal ...

Posted by vipul73 on Sat, 02 Apr 2022 10:16:37 +0300

Daily algorithm & interview questions, 28 days of special training in large factories - the 24th day (operator)

Reading guide Fat friends, in order to better help new students adapt to algorithms and interview questions, we recently started a special assault step by step. In the last issue, we completed 21 days of dynamic programming, and now we will make a 28 day summary of various algorithms. What are you waiting for? Come and have a 28 day chal ...

Posted by cedtech31 on Sat, 02 Apr 2022 06:24:59 +0300

I thought I was proficient in Android event distribution mechanism, but I was stunned by the interviewer

The source code in the article is based on 8.0 preface Event distribution mechanism is not only the core knowledge point, but also the difficulty. It is also a major problem of View and the theoretical basis of sliding conflict resolution. Therefore, it is very important to master the event distribution mechanism of View. 1, Basic understa ...

Posted by viraj on Fri, 01 Apr 2022 04:08:43 +0300

What is the difference between alicbarrier and CountDownLatch

introduction Our previous article CountDownLatch, the three powerful tools of Java high concurrency programming foundation It has a disadvantage that its counter can only be used once, that is, when the counter (state) is reduced to 0, if another thread calls the await() method, the thread will pass directly and will not wait for the execution ...

Posted by MarkR on Fri, 01 Apr 2022 02:26:14 +0300

[gold, silver and silver] summary of common questions in Js interview

Summarize some knowledge of front-end js, sort out the notes and share with you. Some knowledge will often be asked during the front-end interview, so make a record and hope to be helpful to you. If you have any questions, you can point out and actively correct them.If you like, you can like or leave a message. I will continue to update the int ...

Posted by curtm on Wed, 30 Mar 2022 09:48:10 +0300

Interview | JS classic interview questions (this, closure, prototype...) With answers

Code words are not easy, and helpful classmates hope to be able to pay attention to my WeChat official account: Code program life, thank you! Code self use and self access. Mind map 1, Variable promotion Interview questions 1. Ask the following output results if( !("a" in window) ){ var a = 12 } console.log(a) // undefined ...

Posted by rotarypot on Wed, 30 Mar 2022 01:23:01 +0300