Programmer Think

1, Custom error analyzer First throw an exception in the main method: @SpringBootApplication public class P1Application implements CommandLineRunner { public static void main(String[] args) { final SpringApplication application = new SpringApplication(P1Application.class); application.run(args); } @Autowired ...

1. Thread synchronization What is thread synchronization? Let's first look at a piece of code of the ticket selling system, and then analyze this problem: package com.test; /** * @decrition Simulated ticket selling thread */ public class Ticket implements Runnable { //Number of votes currently owned private int num = 100; public void ...

data According to the document introductionShiro official documents ↑ the link of Shiro document is an official introduction to the quick start. In fact, it will be easier to understand ruoyi's document about the integration of the framework. If according to the structure 1. Security Manager The Subject body represents the ...

1. Title Description 2. Problem solving ideas Intersection means to have a "global view" of the two arrays. One embodiment of the "global view" in the program is statistics. Therefore, I can use the hash table to count the occurrence times of each element in the two arrays, and then take the small value to build a ne ...

Statistical analysis module Demand: count the number of registrants of online education every day, and use the chart to display the number of registrants preparation Code generation and configuration file omission~~ Database tables: statistics_daily, which stores statistical data CREATE TABLE `statistics_daily` ( `id` char(19) NOT NULL C ...

String & Immutable 1. Concepts String classes are modified by final, and similar final-modified classes include wrapper classes such as Integer, Double, and so on. As we learned in our second grade, final-modified classes are inheritable. In Java, final-modified classes are called "immutable classes". Curious classmates may ask, ...

   according to the business requirements that business developers usually face, we divide the log into operation (request) log and system operation log. The operation (request) log allows administrators or operators to easily query and track the specific operations of users in the system interface, so as to analyze and count user beh ...

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 ...

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 ...