day06 object oriented Basics
This learning content comes from station b: dark horse programmer
Note: I was speechless and failed to punch in. Normally, this should be the fourth day. After listening to the object-oriented part, I didn't understand it. I listened to it again. Now I feel a little on the road, but I know it's only the simplest, and there's more difficult to ...
Posted by AlanG on Mon, 23 May 2022 21:53:09 +0300
Crawl the mv download address of a website based on scratch
Scrapy is well-known. Seeing that the mv of a website is good, it's too troublesome to download it manually, so we use scrapy to grab it.
The basic idea is to study the home page of the website, the list page of movies, and its playing page, obtain the formatted information in the page, the jump relationship from page to page, and finally obta ...
Posted by reyes99 on Sun, 22 May 2022 20:58:28 +0300
Constructor - prototype - object prototype - constructor property - prototype inheritance - prototype chain
1. Constructor
Facing the characteristics of object programming, such as encapsulation and inheritance, can be realized with the help of constructors, but there will be a waste of memory
<script>
// Constructor function names usually start with uppercase letters
// Instance object pointed to by this
function Person(x, y) {
...
Posted by richblend on Sun, 22 May 2022 02:42:35 +0300
Java - detailed explanation of the use of XOR ^
Follow the wechat official account: CodingTechWork to learn and make progress together.
introduction
It's easier to remember the usage of this operator than the one we don't see in the following code.
introduce
concept
XOR is also called semi addition, binary addition without carry. We know that in binary, 1 means true and 0 means fal ...
Posted by kcarroll on Sun, 22 May 2022 02:20:39 +0300
A brief talk on irrotational Treap (based on the balanced tree of literature and art of Luogu P3391)
Let's talk about it. It's really shallow. It's completely based on the following inscription ↓
Luogu P3391
Look at the questions myself. I'm too lazy to stick...
analysis
In fact, there is nothing to analyze. This is a template problem of Splay tree, which solves the interval maintenance problem that can not be solved by general Treap. ...
Posted by springo on Sun, 22 May 2022 00:51:18 +0300
MyBatis: Cache for MyBatis
1. MyBatis first level cache
The first-level cache is at the SqlSession level. The data queried through the same SqlSession will be cached. The next time the same data is queried, it will be obtained directly from the cache and will not be re-accessed from the database.Four situations that invalidate the L1 cache:
Different SqlSession s ...
Posted by vh3r on Sat, 21 May 2022 22:14:55 +0300
Smart pointer [C + +]
Smart pointer [C + +]
RALL mechanism: resource acquisition is initialization, and the technology of using = = local object = = to manage resources (resources here mainly refer to the limited resources in the operating system, such as memory, network socket, mutex, file handle, etc. local object refers to the object stored in the stack, and its ...
Posted by TravisJRyan on Sat, 21 May 2022 03:06:40 +0300
C# observer mode
Programming requirements
The weather station will provide us with data on temperature, humidity and pressure. Among them, four weather forecast software companies have subscribed. They provide different weather services according to the weather data. In this example, the four companies require the Meteorological Bureau to provide a unified ...
Posted by freelancer on Sat, 21 May 2022 00:44:08 +0300
Section II generic data structure
catalogue
1. What is generics?
2. Generics
2.1 generic syntax
2.2 instantiate a generic class
2.2.1} syntax
2.3 erasure mechanism
2.4 upper bound of generics
2.4.1 grammar
2.4.2 implementation of generic methods
3. Packaging
3.1 basic data type and its corresponding packaging type
3.2 packing and unpacking
Today, let's talk abou ...
Posted by dzekic on Sat, 21 May 2022 00:41:24 +0300
Java coding to realize ActiveMQ communication
1, ActiveMQ port
ActiveMQ uses port 616 to provide JMS services
ActiveMQ uses port 8161 to provide management console services
2, JMS overall architecture
Java Message Service
Roughly speaking, Destination queue and topic
3, Basic steps of JMS development
Basic steps of JMS development
1: Create a connection factory
2: Create J ...
Posted by goldberg on Sat, 21 May 2022 00:10:07 +0300