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preface We talked before Talk about how to implement an SPI with interceptor function . At that time, the core idea of our implementation was to use responsibility chain + dynamic agent. Today, let's talk about how to integrate sentinel to realize fuse current limiting through dynamic agent Pre knowledge Introduction to alibaba sentinel Se ...

Scope function selection At present, there are let, run, with and apply   and   also five scope functions. The official document has a table to illustrate the differences between them: To sum up, there are several differences: 1. apply and also return context objects. 2,let,run   And with return lambda results. 3. The ref ...

preface It was in 2002, and MySQL 4.1 began to support UTF-8 coding RFC 2279 It is stipulated that the code uses 1 ~ 6 bytes to store a single character, and MySQL developers checked it in September of the same year Source code The UTF-8 encoding is changed from the maximum 6 bytes to 3 bytes, so there is the current UTF8MB3. As we all know, U ...

1.GET request GET request parameters are spliced after the url. This method is called query parameters. In fact, POST requests can also be requested using the query parameter. 2. Browser behavior: Form submission action: url Address, the address where the server receives form data method: Submit server's http Method, generally post and get n ...

@Go MySQL transfer of data real-time incremental synchronization tool: https://blog.csdn.net/weixin_...Installation, configuration and Kibana foundation of Elasticsearch notes: https://blog.csdn.net/weixin_...Go MySQL transfer official Manual: https://www.kancloud.cn/wj596...Environment installation of GO notes: https://blog.csdn.net/weixin_... ...

abstract class The core of object-oriented programming is abstract oriented programming, which generally depends on abstraction rather than concrete in the development process public class A{ public void pp(Pig pig)}//If you use concrete classes, there is no flexibility. If Cat is required, only the source code can be modified public class ...

I remember there was a classic interview question: how to output from 1 to 100 in sequence with multiple threads? The last chapter talked about the use and principle analysis of locks in Java. The above interview questions should be handy This chapter mainly talks about the realization of production and consumption queue and Condition source c ...

1, Dynamic SQL   one of the powerful features of MyBatis is its dynamic SQL. If you have experience using JDBC or other similar frameworks, you can realize how painful it is to splice SQL statements according to different conditions. When splicing, make sure you don't forget the necessary spaces, and pay attention to omitting the comm ...

Basic Introduction Provides a surrogate for an object to control access to it. That is, to access the target object through a proxy object, the advantage is that on the basis of the target object, additional functional operations can be enhanced, that is, to extend the function of the target object.Proxied objects can be remote objects, expens ...

review structure Sequential structureBranch structure ifLoop structure forSelect structure switch variable Member variablelocal variable The Fifth Day while Loop Structure: while (loop condition){ Circulatory body; } do-while Loop Structure: do{ Circulatory body; }while (cycle condition); Differences between the three cycles fo ...