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This paper mainly analyzes the startup process of Producer in RocketMQ. The version of RocketMQ is: 4.2.0 release. 1, Sequence diagram According to the source code, the timing of the Producer startup process is drawn once:   2, Source code analysis 1 start(): DefaultMQProducer starts. The main functions of DefaultMQProducer are impl ...

Today, when using glide to install golang project dependencies, an error is reported as follows: (the second time, make a record today) [ERROR] Failed to set version on golang.org/x/sys/unix to : Cannot detect VCS [ERROR] Failed to set version on golang.org/x/text/transform to : Cannot detect VCS [ERROR] Failed to set version on golang.org/x ...

introduce Learn some basic knowledge first @Binds @IntoSet @IntoMap @IntoXXXX Let's first introduce how to design MVVM when it is not dagger2 If you don't know how to use databinding, the following video is recommended Android Data Binding practice - Beginner Level Android Data Binding practice - Advanced Let's p ...

Catalog Catalog Effect Code js html Actual code Download Shortcut links Effect Code js function UploadImg(file) { var MAXWIDTH = 260; var MAXHEIGHT = 180; var div = document.getElementById('preview'); if (file.files && file.files[0]) { div.innerHTML = '<img id=i ...

Briefly: Requirements understanding: Ordinary Observable in Rxjava will transmit data when the observer subscribes, but sometimes we want to control the data transmission by ourselves. For example, we need to use the connectable Observable in Rxjava to fulfill this requirement after having a specified observer or all observers subscribing. This ...

The essence of the simple factory pattern is that a factory class dynamically determines which instances of a product class should be created (these product classes inherit from a parent class or interface) according to the parameters passed in. ——Baidu Encyclopedia Picture from Baidu Encyclopedia For example: F ...

- 1. * create head navigation bar * import React from "react"; import { createTabNavigator } from "react-navigation"; import List from "./List"; //Add a reuse const Good = () => { return <List />; }; const Share = () => { return <List />; }; const Ask = () => { return <List />; }; const Jo ...

Source code https://github.com/zhongchengyi/zhongcy.demos/tree/master/mongo-morphia-demo Preface Morphia is a library that java uses orm to operate mongodb. But by default, when using morphia to access enum, it is accessed by name. We need to access enum by value. As shown in the figure: the schoolClassLevel1 field is accessed by enum name ...

Art template is a simple and super fast template engine. It uses scope pre declaration technology to optimize the template rendering speed, so as to achieve the running performance close to the JavaScript limit, and supports both NodeJS and browsers. Document address: https://aui.github.io/art-template/docs/index.html ...

First, let's take a look at the effect, first update 5 data items from top to bottom, then slide to the bottom and pull up to add 5 data items from the bottom to the top: We use a third-party library, so we first add it in the gradle configuration file: implementation 'com.android.support:recyclerview-v7:25.3.1' imp ...