Master Kotlinx Coroutines Core framework: Implement collaborative asynchronous programming in the Java library Kotlinx Coroutines is an asynchronous programming framework for Kotlin programming language, which can achieve synergistic asynchronous programming in the Java class library.This article will introduce how to use the Kotlinx Coroutines Core framework to achieve asynchronous programming. # What is a collaborative asynchronous programming? In traditional asynchronous programming, we use the callback function or Future/Promise to handle the results of asynchronous operations.In this way, it is necessary to significantly manage the state of the callback function or Promise, and it is easy to have the problem of callback hell. In the collaborative asynchronous programming, we can write asynchronous operations in a similar synchronous code.By using Coroutines, we can regard asynchronous code as a sequential code block without explicitly processing the callback function or Promise. # How to use KOTLINX Coroutines Core framework? First, we need to add Kotlinx Coroutines Core framework to the project.In Gradle, you can add dependencies in the following ways: groovy dependencies { implementation "org.jetbrains.kotlinx:kotlinx-coroutines-core:1.4.2" } Next, we can use the SUSPEND keywords provided by the Kotlinx Coroutines framework to define the coroutine function.The Suspend keyword is used to mark a function that can be hung and continue to execute later.In this way, we can perform time -consuming asynchronous operations in the coroutine function without blocking the main thread. Below is a simple example, showing how to use Kotlinx Coroutines Core framework to perform asynchronous operations: kotlin import kotlinx.coroutines.* suspend fun fetchData(): String { delay (1000) // Simulation time -consuming operation return "Data fetched!" } fun main() { println("Start") // Create an coroutine scope runBlocking { // Start a coroutine val result: Deferred<String> = async { fetchdata () // Call the corout function } // The results of obtaining asynchronous operations when the coroutine runtime val data = result.await() // Output results println(data) } println("End") } In the above example, we define an coroutine function called fetchdata. This function uses the delay function to simulate a time -consuming asynchronous operation and return a string.In the main function, we used the RunBlocking function to create a coroutine scope and started a coroutine in it.Through the ASYNC function, we call the FETCHDATA coroutine function to perform asynchronous operations, and then use the AWAIT function to obtain the results of the asynchronous operation. Finally, we output the asynchronous operation results obtained in the coroutine.If you run this code, you can see that in the output result, "START" will be output before "data fetchd!", And "End" will be output after "data fetchd!".This proves that the coroutine can handle asynchronous operations in order. # in conclusion Kotlinx Coroutines is a powerful asynchronous programming framework that can achieve synergistic asynchronous programming in the Java library.By using the Kotlinx Coroutines Core framework, we can write asynchronous operations in a similar synchronous code to avoid the problem of callbacking hell.Through the introduction of this article, you should have a certain understanding of how to use the Kotlinx Coroutines Core framework, and be able to achieve synergistic asynchronous programming in the Java library.