Programmer Think

1, Overview After using docker to create a container, I enter the container and find that many common tool commands do not exist. For example, I want to use ping command to test whether the network is unblocked. I find that this command cannot be found in the container, as shown below: root@kuboard-5967d77d89-h2hgn:/# ping www.baidu.com bas ...

First of all, TS mainly solves the main problem of unclear js type, so we should write its type when defining variables Basic data type code let b : number // At this time, the variable of b must be number, or an error will be reported let isDone: boolean = false; b = 1 // Of course, you will say whether there are other types. Of course, ...

1, Hungry Han style Constructor privateClassExpose a static method 1. Static constant Test class public class SingletonTest01{ public static void main(String[] args){ Singleton singleton = Singleton.getInstance(); Singleton singleton1 = Singleton.getInstance(); System.out.println(singleton == singleton1 ); } } Hungry Han for ...

1. Introduction to Exchanger Exchanger - Exchanger, JDK1. A synchronizer was introduced at 5th hour, and it can be seen literally that the main function of this class is to exchange data. Exchanger is a bit like CyclicBarrier, we know that CyclicBarrier is a fence, and threads that reach it need to wait for a certain number of other threads t ...

JS prototype prototype chain value and reference type 1 Review 1.1 Object type 1. establish Object Object of type ① Direct quantity {} ② Object Constructor ③ Object function 2. Read / write object properties . [] Must use[]There are two cases of syntax:① The attribute name does not conform to the identity name specifica ...

2, Queue The operation can only be performed at one end of the list (the operation can be performed at the other end of the list) through the specified order of the list (the operation can be performed at the other end of the list). Queue: a First In First Out linear table, called FIFO for short. The end allowed to be inserted is the ...

What is AOP AOP (Aspect Oriented Programming) means: aspect oriented programming, which realizes the unified maintenance of program functions through precompiled mode and runtime dynamic agent. AOP is a continuation of OOP. It is not only a hot spot in software development, but also an important content in Spring framework. It is a derivative ...

Chapter 7 login and authentication Learning objectives Can use BCrypt for password encryption Getting started with Spring Security Complete green orange login authentication Complete the green orange menu display Complete user login log Project sequence-7: https://github.com/Jonekaka/https-github.com-Jonekaka-javaweb-qingcheng-7-82.git 1 ...

1, Analysis of shopping cart data model in E-commerce Functions realized in shopping cart: add shopping cart, view shopping cart, edit shopping cart sku, edit commodity data, select multiple commodities in shopping cart to settle, view the total number of commodities in shopping cart, delete shopping cart, share shopping cart, etc Current sho ...

OpenStack deployment 1, Environmental preparation 1. Network environment hostIPcontroller10.0.0.51compute110.0.0.61 Modify hosts file cat /etc/hosts 10.0.0.51 controller 10.0.0.61 compute1 Close selinux and firewalld cat env_set.sh #!/bin/bash systemctl stop firewalld systemctl disable firewalld setenforce 0 sed -i 's/SELINUX=enforci ...