hadoop familiar with common HDFS operation IDEA installation
Familiar with common HDFS operation
1. Create a txt file in the "/ home/hadoop /" directory of the local Linux file system, where you can enter some words at will 2. View file location locally (ls) 3. Display file content locally
cd /home/hadoop
ls
touch test.txt
vim test.txt
cat test.txt
4. Use the command to upload the "t ...
Added by alexjb on Thu, 17 Feb 2022 11:21:35 +0200
18 details of Spring transaction propagation mechanism
What is the transaction propagation mechanism
The propagation mechanism of transactions, as the name suggests, is how to propagate transactions between multiple transaction methods.
For example, method A is A transactional method. Method B is called when method A executes. Whether method B has A transaction or not and whether it needs A tr ...
Added by rajan on Thu, 17 Feb 2022 11:16:16 +0200
SpringBoot -- underlying annotation
prefaceThis article records the process of learning the SpringBoot framework.Official website: Spring | Home edition:Maven: 3.6.1JDK: 1.8SpringBoot: 2.3.4Project construction:Create a maven project:pom.xml configuration file:<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="ht ...
Added by remmargorp on Thu, 17 Feb 2022 11:12:24 +0200
[Machine Learning] linear regression and logistic regression (including code)
The difference and relation between linear regression and logistic regression
Both linear regression and logistic regression are linear regression in a broad sense. But they are different.
methodIndependent variable (characteristic)Dependent variable (result)relationshipapplicationLinear regressionContinuous or discreteContinuous real num ...
Added by lupes on Thu, 17 Feb 2022 11:03:08 +0200
SpringBoot -- basic introduction
prefaceThis article records the process of learning the SpringBoot framework.Official website: Spring | Home edition:Maven: 3.6.1JDK: 1.8SpringBoot: 2.3.4brief introduction"Spring Boot makes it easy to create stand-alone, production-grade Spring based Applications that you can 'just run'."advantage Create stand-alone Spring applications
Create ...
Added by terryl on Thu, 17 Feb 2022 10:53:29 +0200
Go Web Learning - standard library net/http usage
Implement a simple http service
package main
import (
"fmt"
"log"
"net/http"
)
func main() {
http.HandleFunc("/", func(rw http.ResponseWriter, r *http.Request) {
fmt.Fprint(rw, "hello word")
})
log.Fatal(http.ListenAndServe(":9777", nil))
}
Principle analysis:In the first line of the main() function, we use ...
Added by burntheblobs on Thu, 17 Feb 2022 10:52:33 +0200
Hadoop cluster ecological construction
Hadoop cluster construction (continuous update)
The relevant resource files that are not used in this paper, the extraction code eeee
1: Preparations to be completed before starting construction
Built Linux serverYou can access the public network (ping www.baidu.com), and you can ping itXshell connection (can be omitted)Server version infor ...
Added by ijug.net on Thu, 17 Feb 2022 10:50:58 +0200
Detailed explanation of Vue life cycle
1.beforeCreate
After instance initialization, data observation and event/watcher event configuration are called before.
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-sca ...
Added by ManicMax on Thu, 17 Feb 2022 10:46:14 +0200
Introduction to Lambda expressions, read this article is enough!
Introduction to LambdaLambda expression is a new feature of JDK8. It can replace most anonymous inner classes and write more elegant Java code. Especially in collection traversal and other collection operations, it can greatly optimize the code structure.JDK also provides a large number of built-in functional interfaces for us to use, making th ...
Added by aconway on Thu, 17 Feb 2022 10:36:38 +0200
Application of double buffer mechanism in some software or framework
As we all know, the JVM's garbage removal algorithm is a copy removal algorithm used in the young generation, which is why the young generation is divided into two memory spaces of the same size: S0 and S1. When S0 is full, copy it to S1, and then empty S0. Of course, GC will tidy up the memory and make it continuous. What other common software ...
Added by njwan on Thu, 17 Feb 2022 10:35:21 +0200