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definition: The parent class derives a subclass, which inherits the parent class. The subclass can obtain the properties and methods of the parent class use: extends keyword, which declares that the subclass inherits from the parent classsuper keyword, used to refer to the parent object (the parent object will be created before the c ...

Interview questions 1. It is required to print A1B2C3... Z26 in thread order Solution 1 (LockSupport): The code is as follows: static Thread t1 = null, t2 = null; public static void main(String[] args) { t1 = new Thread(() -> { for (char a ='A'; a <= 'Z'; a++) { System.out.print(a); ...

The source code of this article is based on jdk1 8 . Thread state In the Thread class, the Thread status is realized through the threadStatus property and the State enumeration class: /* Java thread status for tools, * initialized to indicate thread 'not yet started' */ private volatile int threadStatus = 0; public enum State { /** ...

Vue framework Vue3 Foundation: front end engineering, webpack, plugin, loader, Source Map Vue framework is the hottest front-end framework at present. In order to cooperate with springBoot framework to complete the construction of a complete project in the later stage, we have shared the knowledge of Vue, such as ES6 modularization ...

MyBatis learning What is MyBatis? MyBatis is the MyBatis SQL Mapper Framework for Java (sql) Mapping) MyBatis is an excellent persistence layer framework, which supports custom SQL, stored procedures and advanced mapping. MyBatis eliminates almost all JDBC code and the work of setting parameters and obtaining result sets. MyBatis can config ...

Refer to Niuke advanced project tutorial 1. Functional requirements for displaying login information Functions to be realized: Users should display different header information when accessing the page in two states: not logged in and logged in That is, not logged in status: Visit the home page, with login and registration ...

6.1 class and object A class is a data typeAn object is a concrete instanceIf the attribute (member variable) is not assigned a value, it has a default value, and the rules are consistent with the array 6.2 existence form of object in memory 6.3 memory allocation mechanism of classes and objects 6.4 method calling mechanism and princi ...

Chapter 1 Introduction to spring MVC Spring Framework version 4.3.29 RELEASE What is spring MVC 1. Spring Part of the family 2. yes JavaWeb Solution of controller layer in three-tier architecture 3. Is based on MVC Ideological framework -- Model -- View -- Controller Spring MVC knowledge point outline Spring MVC ...

Background introduction In some cases, we are using Kubernetes as the cloud platform for business applications. We want to realize the blue-green deployment of applications to iterate the application version. lstio is too heavy and complex, and it is positioned in flow control and grid governance; Ingress nginx introduces Canary function in ve ...

1, Basic concepts of transaction 1. What is a transaction (1) Transaction is the most basic unit of database operation. Logically, a group of operations either succeed or fail if one fails (2) Typical scenario: bank transfer 2. Transactions have four characteristics (ACID) (1) Atomicity: to succeed, to fail, to fail (2) Consistency: the total a ...