Recent Posts
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Java simple class object instantiation process
Suppose there is such a class: Person p = new Person(); The creation process of the whole object is as follows: -
Collection of Java (set, list, map)
The Java collection class is stored in the Java, UTI package and is a container for storing objects. Java collections …… -
Ternary operator of Java
Logical operation? m : n; If the logical operation is true, M is returned; otherwise, n is returned example: Judge the…… -
Object type conversion of Java
Conversion between basic data types: public class Person extends Object{} public class Student extends Person{} Cast J…… -
Bit operator of Java
Integer to binary: integer toBInaryString(6) < <: move left, 3 < < 2 = 3 * 2 * 2 = 12 >>: shift righ…… -
Ternary operator of Java
Logical operation? m : n; If the logical operation is true, M is returned; otherwise, n is returned example: Judge the…… -
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Domain name query
[boce] (https://www.boce.com/http/api.hengyuegz.cn) [ping] https://www.ping.cn/dns/page.hen…… -
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JSP custom tag / custom tag packaging
There is such a business requirement: When editing a user, we need to set the user's role. When we go to the editing p…… -
Talk about constants and variables
What are constants and variables Constant: the amount that the program will not change during operation is called a co…… -
A brief introduction to Servlet
Servlet introduction: Servlet is a web server-side programming technology, which implements Java classes with special …… -
How to choose the Java version for novices on the road
@ When you first enter the Java pit, there are so many versions of Java. If you want to know what version you should d…… -
IO stream summary
Java stream classification: 1. According to the flow direction: How to distinguish the input stream from the output st…… -
Java file upload and download
Two core packages should be introduced for file upload commons-fileupload-1.2. 1.jar commons-io-1.4. jar The following…… -
JDK1. 8 new feature (2): collectors collector class
I What are collectors? Java 8 API adds a new abstraction called stream. We can easily manipulate stream objects with t…… -
lambda expressions
Properties of lambda expressions: Lambda expression can be understood as a way to concisely represent a transitive ano…… -
A brief introduction to cookies
reflection: HTTP is a stateless protocol. When a client sends a request to the server, the connection is closed after …… -
Java collection source code analysis (3): ArrayList
summary In the previous article: Java collection source code analysis (II): list and abstractlist and Java collection …… -
Download and installation of jdk8 for novices and configuration of path environment variables
Some things are not often used and will always be forgotten, so I want to write them down so that I can find them when…… -
What is the HTTP protocol
Concept: Http: Hyper Text Transfer Protocol. effect: Let's think about a problem first. As shown in the figure below, …… -
Puzzle 2: process thread, parallel concurrency, synchronous and asynchronous, blocking fee, blocking
1、 Serial, parallel, concurrent 1. Name explanation Concurrency and parallelism focus on whether programs are execute…… -
Implementation of dynamic aspect based on javassist and javaagent
1、 Background introduction 1. Requirement description The requirement is to add a section of business code before and…… -
JDK1. 8 new features (I): stream
I What is stream? 1. General The Java 8 API adds a new abstraction called stream, which allows you to process data in …… -
Multi tenant personalized service routing
Scene description Solution Design a personalized service table to store the personalized services of the tenant. If th…… -
Jdk8 string class knowledge summary
1、 Overview Java's string class can be said to be the most practical class in daily life, but most of the time it is …… -
On Java collection (I): HashMap
1、 Overview HashMap is probably the implementation of the map interface we most often use. Without much more, let's t…… -
The reason why the session has not expired and its saved data is lost without reason
Question: A function we often do is to save the login user information to the session and display the login user name …… -
Java collection source code analysis (II): list and abstractlist
summary @R_ 301_ 2444@ this article basically introduces the upper structure of the list interface, that is, the itera…… -
Java collection source code analysis (I): collection and abstractcollection
summary As we know, the container in Java is divided into map set and collection set, and the container in collection …… -
Array of java series
I was going to review the annotation as today's push, but it's too late. Let's take a look at the array. The array is …… -
Observer design pattern of design pattern
Recently, I'd like to supplement the knowledge related to design patterns. About observer design patterns, I mainly le……