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Article directory brief introduction Characteristic data structure Before JDK1.8 After JDK1.8 JDK1.7 VS JDK1.8 comparison Inheritance diagram Member variables Construction method Static inner class Node TreeNode Core method hash() algorithm put() method resize() method treeifyBin() method get() metho ...

This article explains how to deploy two vue projects on a nginx, and the difference between root and alias. routing problem First, assume the main domain name is www.yuming.com. The subdomain to be bound is www.yuming.com/two The following figure first shows the nginx configuration of a project. api i ...

Purpose and principle: When handling exceptions, if we want to return different pages according to the actual situation, @ ControllerAdvice and @ ExceptionHandler are generally used to handle application level exceptions, and some container level errors cannot be handled, such as throwing exceptions in Filter. SpringBoot will have a default pag ...

I've written a time-based task based on quartz before. The front-end and distribution need to be improved https://my.oschina.net/wangnian/blog/758054 , which is directly based on time. In fact, it will be executed after and when. Today is my first day back to work. Many of my friends have been back to work. They have been wearing masks for hal ...

Article directory 1, The role of RequestMapping 2, Properties of RequestMapping 1.method attribute 2.params attribute 3.headers property 1, The role of RequestMapping Function: @ RequestMapping annotation can complete url request mapping. It can work on methods. @RequestMapping("/addUI") ...

SQL Injection (intro) 0x02 select department from employees where first_name='Bob'; 0x03 update employees set department='Sales' where first_name='Tobi'; 0x04 alter table employees add column phone varchar(20); 0x05 grant alter table to UnauthorizedUser 0x09 SELECT * FROM user_data WHERE first_nam ...

Design patterns are essential skills for good programmers and are often mentioned in interviews. Preface IT industry has a high job-hopping rate, which makes it less frequent to interview.As an interviewer, if all the other knowledge of the candidate is OK, I will end up referring to <b>design patterns</b>related content.If the ...

Java13 Core Classes Without special instructions, all my study notes were taken from Mr. Liao and deleted. Introduction I went around to my senior year and learned C, C++, C_#, Java, Python, one thing at a time, and finally picked up Java.Therefore, I advise you to master one object-oriented, although Python is easy to write, but after all, ...

I read some articles about closures, and I saw them everywhere, but I didn't explain exactly how it works - every time I was told to use it : // Create a new anonymous function, to use as a wrapper (function(){ // The variable that would, normally, be global var msg = "Thanks for visiting!"; // Binding a new function to a global ...

Java programs sometimes create multiple threads in the main thread to execute tasks, and then summarize the tasks of all threads before the main thread finishes executing. In the past, thread join method can be used, but this method is not flexible enough. We can use CountDownLatch class to achieve more elegant, and if thread pool is used, ther ...