Horsepower in Android or once again on RecyclerView.LayoutManager

3r3133. Horsepower in Android or once again on RecyclerView.LayoutManager 3r33737.
 3r33724. According to the author, the article can be useful in the same way as it is for novice Android developers making their first steps in such an exciting area. The history of the subject of this note began with the idea to equip the educational project with the so-called “wow effect”. How much it was possible to judge you. I ask all curious under kat.
 3r33724. 3r311.
 3r33724. A demo project with all this ugliness can be found on GitHub at 3r3-3695. link
.
 3r33724.
 3r33724. At the core of the screen that interests us is the well-loved RecyclerView. And the highlight is the fact ...
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Top reports of JPoint 2018: Java /JVM and its performance, Kotlin, Spring, Docker

Top reports of JPoint 2018: Java /JVM and its performance, Kotlin, Spring, Docker 
3r3-31.
We have already posted videos of JPoint 2018 reports on YouTube and, specifically for the Java hub on Habré, we have made a traditional selection of the best of them according to conference visitors.
 
As usual, the top “junior” reports, in the end - with the highest rating. Of course, this does not mean that one report is much worse than another: if you change the calculation method, places can easily change. In reality, we changed it, now the “soft quorum” version of the rating is used, taking into account the number of participants present at the report. This approach has its drawbacks ...
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Fault Injection: your system is unreliable if you have not tried to break it

Hi, Habr! My name is Pavel Lipsky. I am an engineer, I work in the company Sberbank-Technology. My specialization is testing the fault tolerance and performance of backends of large distributed systems. Simply put, I break other people's programs. In this post I will talk about fault injection - a testing method that allows you to find problems in the system by creating artificial failures. To begin with, I came to this method, then we will talk about the method itself and how we use it.
 
 
Fault Injection: your system is unreliable if you have not tried to break it ...
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Ten things you can do with GraalVM

Ten things you can do with GraalVM  
From the translator: GraalVM is a new, interesting technology, but on Habré there are not many articles on it that could show examples of the possibilities of Graal. The article below is not just a listing of what GraalVM can do, but also a small workshop similar to the one that Chris Seaton and Oleg Shelayev conducted on Oracle CodeOne 2018. Following the author, I urge you - try to make examples from the article, this is really interesting.
 
In GraalVM there are many different things, and if you heard this name before, or even saw reports, there are still many things that you probably don’t know ...
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Oleg Dokuka about reactive development on jug.msk.ru

December 1? 2018 at a meeting of the community of Moscow Java-developers 3r3202. jug.msk.ru
Oleg Dokuka spoke about the features of reactive development in the programming language 3r32222. Java 3r32323. . 3r3197.  
3r3197.  
Oleg Dokuka about reactive development on jug.msk.ru 3r3197.  
3r3197.  
About speaker 3r3122. 3r3197.  
Oleg is an active speaker at conferences such as 3-33222. JBreak [/i] , Joker , JEEConf , GeeCON , Voxxed Days and others. Project contributor Reactor and co-author of the book [leech=https://www.packtpub.com/application-development/hands-reactive-programming-spring-5] ...
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Compile Kotlin: JetBrains VS ANTLR VS JavaCC

Compile Kotlin: JetBrains VS ANTLR VS JavaCC
 
How quickly does Kotlin parse and what does it matter? JavaCC or ANTLR? Is the source code from JetBrains suitable?
 
Compare, fantasize and wonder.
 
3r311.
 

tl; dr


 
3r33434. JetBrains are too hard to carry, ANTLR is hyip but unexpectedly slow, and JavaCC is still too early to write off. 3r33434.
 
 
Parsing a simple Kotlin file with three different implementations:
 
3r33333.  
3r33399.  
Implementation  
First run  
The 1000th launch of  
jar size (parser)  
 
3r33399.  
3r33410. JetBrains  
3r33410. 3254ms  
3r33410. 16.6ms  
3r33410. 35.3MB ...[/h]
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From aircraft to programmers in one year, or how to become a Jedi

From aircraft to programmers in one year, or how to become a Jedi 3r3196. 3r3-31. 3r3179. 3r33180. Yoda: Master Qui-Gon, is there anything else to say to you? 3r3181.  3r3196. Qui-Gon Jin: With your permission, Master. I found the point of concentration of the Great Force. 3r3181.  3r3196. Yoda: Concentration, you said? 3r3181.  3r3196. Mace Windu: Inside a living being? 3r3181.  3r3196. Qui-Gon Jin: In the boy. His cells contain the highest level of midichlorians from all that I have seen. He was probably conceived by midichlorians. 3r3181.  3r3196. Mace Windu: You are hinting at a prophecy about the Chosen One that will bring balance to the Force. Do you believe ...
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Create a Shape Map RF map in Power BI

Create a Shape Map RF map in Power BI3r3124. Hello! Today let's talk about the "spatial" analysis in Power BI. On the platform for business intelligence, you can read 3r335. here
. I will analyze one aspect in the post - how to draw the RF map in the Shape Map. 3r3143. Map 3r3144.  
Card 3r3142 filled. 3r3144.  
3r350. ArcGIS Maps for Power BI
3r3144.  
3r361 Shape Map
3r3144.  
3r3338.
 
3r3124. 3r3117. Each has its own advantages and disadvantages, so it is better to consider them on the basis of a specific task 3r3r118. . 3r3143.
 
3r3124. The article will be considered a visual element ...
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Devops, JUnit5 and microservice testing: a subjective view of the Moscow “Heisenbag”

Devops, JUnit5 and microservice testing: a subjective view of the Moscow “Heisenbag” 3r33333.  
3r33333.  
On December 6-? the fifth Heisenbag conference took place in Moscow. 3r33333.  
Her slogan is “Testing. Not only for testers! ”, And for two years of regularly visiting Heisenbagov, I (formerly a Java developer, now a technical leader in a small company that had never worked in QA) managed to learn a lot about testing and implement a lot in our team. I want to share a subjective review of the reports I remembered this time. 3r33333.  
3r33333.  
Liquid Software ) 3r349. 3r33333.  
3r33333.  
Those who are engaged in Java and attend conferences of the JUGRU Group, Baruh ...
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How to handle errors on JVM faster

How to handle errors on JVM fasterThere are various ways to handle errors in programming languages: 3r33371.
 
 
standard exceptions for many languages ​​(Java, Scala and other JVM, python, and many others) 3r3105.  
status codes or flags (Go, bash)
 
various algebraic data structures, the values ​​of which can be both successful results and error descriptions (Scala, haskell, and other functional languages) 3r3105.  
 
Exceptions are used very widely, on the other hand they are often said to be slow. But opponents of the functional approach often appeal to performance. 3r33333.
 
Recently, I have been working with Scala, where ...
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