Kotlin协程(Coroutine)的使用以及源码分析

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原创最新推荐文章于 2026-07-08 12:46:44 发布 1k 阅读 AI 写同款· GEO 优化 ›

Kotlin 协程源码解析本文适合有协程使用基础并想了解内部原理开发者一、什么协程(Coroutines) 看下Android文档对协程的定义：协程是一种并发设计模式，您可以在 Android 平台上使用它来简化异步执行的代码。协程是在版本 1.3 中添加到 Kotlin 的，它基于来自其他语言的既定概念。本文主要分析协程以下功能的内部实现编译器是如何实现协程的异步操作的同步调用？（如何帮我们解决异步操作回调地狱呢？） coroutine是如何通过CoroutineContext来切换上下文的？ coroutine挂起和. 阅读详情

对于了解协程（微线程，Coroutine），其实很早就有协程的概念，在Lua,Python,go语言中较为常见Android在kotlin拓展库kotlinx.coroutines去提供使用。

首先讲起进程和线程

进程拥有切换和打开的进程表，文件资源、数据资源、独立的内存空间。

线程从属于进程，是程序的实际执行者，一个进程至少包含一个主线程，也可以有更多的子线程，线程拥有自己的栈空间。

线程具有五种状态：初始化、可运行、运行中、阻塞、销毁。

协程

协程不同与进程或线程是比线程更加轻量级的存在，一个进程可以拥有多个线程，一个线程可以拥有多个协程，协程有自己控制的上下文。

进程和线程都是由是操作系统的调度切换策略去执行，而协程的切换时机则是用户自己的程序所决定的。

协程是不需要多线程的锁机制，减少资源消耗。

协程提升CPU利用率，减少线程切换，提升程序运行效率。

总结协程：可控制轻量级语法糖。

常用API

runBlocking

//启动执行协程任务

launch

//执行协程任务
//启动参数

当前协程上下文，可声明切换调度器模式
context: CoroutineContext = EmptyCoroutineContext
可自定义启动方式
start: CoroutineStart = CoroutineStart.DEFAULT,
闭包形式的协程函数
block: suspend CoroutineScope.() -> T

asyns/await

//执行协程任务/得到返回结果

协程工厂函数

val scope = MainScope()
scope.async(Dispatchers.Default) {}
scope.launch {}
scope.cancel()

withContext

withContext(Dispatchers.Default){}
Dispatchers提供四种不同属性提供不同的线程支持和操作Default Main Unconfined IO

反编译源码分析

runBlocking

  fun main() = runBlocking {
        listCoroutineScope()
    }
//反编译源码
 
   public final List<Font> main() {
        return (List) BuildersKt__BuildersKt.runBlocking$default((CoroutineContext) null, new FontService$main$1((Continuation) null), 1, (Object) null);
    }

// FontService$main$1 
@Metadata(bv = {1, 0, 3}, d1 = {"\u0000\u0012\n\u0000\n\u0002\u0010!\n\u0002\u0018\u0002\n\u0002\u0018\u0002\n\u0002\b\u0002\u0010\u0000\u001a\b\u0012\u0004\u0012\u00020\u00020\u0001*\u00020\u0003HŠ@¢\u0006\u0004\b\u0004\u0010\u0005"}, d2 = {"<anonymous>", "", "Lcom/hyfontstudio/fontspro/base/Font;", "Lkotlinx/coroutines/CoroutineScope;", "invoke", "(Ljava/lang/Object;Ljava/lang/Object;)Ljava/lang/Object;"}, k = 3, mv = {1, 1, 16})
/* compiled from: FontService.kt */
final class FontService$main$1 extends SuspendLambda implements Function2<CoroutineScope, Continuation<? super List<Font>>, Object> {
    int label;
    private CoroutineScope p$;

FontService$main$1(Continuation continuation) {
    super(2, continuation);
}

public final Continuation<Unit> create(Object obj, Continuation<?> continuation) {
    Intrinsics.checkParameterIsNotNull(continuation, "completion");
    FontService$main$1 fontService$main$1 = new FontService$main$1(continuation);
    CoroutineScope coroutineScope = (CoroutineScope) obj;
    fontService$main$1.p$ = (CoroutineScope) obj;
    return fontService$main$1;
}

public final Object invoke(Object obj, Object obj2) {
    return ((FontService$main$1) create(obj, (Continuation) obj2)).invokeSuspend(Unit.INSTANCE);
}

public final Object invokeSuspend(Object $result) {
    IntrinsicsKt.getCOROUTINE_SUSPENDED();
    if (this.label == 0) {
        ResultKt.throwOnFailure($result);
        CoroutineScope coroutineScope = this.p$;
        return FontService.Companion.listCoroutineScope();
    }
    throw new IllegalStateException("call to 'resume' before 'invoke' with coroutine");
}
}

 fun listCoroutineScope() =
             runBlocking {
            async {
                print("Thread:::${Thread.currentThread().name}")
            }.await()


    }
//反编译源码
   public final List<Font> listCoroutineScope() {
        return (List) BuildersKt__BuildersKt.runBlocking$default((CoroutineContext) null, new FontService$Companion$listCoroutineScope$1((Continuation) null), 1, (Object) null);
    }
//FontService$Companion$listCoroutineScope$1 
@Metadata(bv = {1, 0, 3}, d1 = {"\u0000\u0012\n\u0000\n\u0002\u0010!\n\u0002\u0018\u0002\n\u0002\u0018\u0002\n\u0002\b\u0002\u0010\u0000\u001a\b\u0012\u0004\u0012\u00020\u00020\u0001*\u00020\u0003HŠ@¢\u0006\u0004\b\u0004\u0010\u0005"}, d2 = {"<anonymous>", "", "Lcom/hyfontstudio/fontspro/base/Font;", "Lkotlinx/coroutines/CoroutineScope;", "invoke", "(Ljava/lang/Object;Ljava/lang/Object;)Ljava/lang/Object;"}, k = 3, mv = {1, 1, 16})
@DebugMetadata(c = "com.hyfontstudio.fontspro.ime.core.FontService$Companion$listCoroutineScope$1", f = "FontService.kt", i = {0}, l = {109}, m = "invokeSuspend", n = {"$this$runBlocking"}, s = {"L$0"})
/* compiled from: FontService.kt */
final class FontService$Companion$listCoroutineScope$1 extends SuspendLambda implements Function2<CoroutineScope, Continuation<? super List<Font>>, Object> {
    Object L$0;
    int label;
    private CoroutineScope p$;

FontService$Companion$listCoroutineScope$1(Continuation continuation) {
    super(2, continuation);
}

public final Continuation<Unit> create(Object obj, Continuation<?> continuation) {
    Intrinsics.checkParameterIsNotNull(continuation, "completion");
    FontService$Companion$listCoroutineScope$1 fontService$Companion$listCoroutineScope$1 = new FontService$Companion$listCoroutineScope$1(continuation);
    CoroutineScope coroutineScope = (CoroutineScope) obj;
    fontService$Companion$listCoroutineScope$1.p$ = (CoroutineScope) obj;
    return fontService$Companion$listCoroutineScope$1;
}

public final Object invoke(Object obj, Object obj2) {
    return ((FontService$Companion$listCoroutineScope$1) create(obj, (Continuation) obj2)).invokeSuspend(Unit.INSTANCE);
}

public final Object invokeSuspend(Object $result) {
    Object coroutine_suspended = IntrinsicsKt.getCOROUTINE_SUSPENDED();
    int i = this.label;
    if (i == 0) {
        ResultKt.throwOnFailure($result);
        CoroutineScope $this$runBlocking = this.p$;
        Deferred async$default = BuildersKt__Builders_commonKt.async$default($this$runBlocking, (CoroutineContext) null, (CoroutineStart) null, new AnonymousClass1((Continuation) null), 3, (Object) null);
        this.L$0 = $this$runBlocking;
        this.label = 1;
        Object await = async$default.await(this);
        if (await == coroutine_suspended) {
            return coroutine_suspended;
        }
        CoroutineScope coroutineScope = $this$runBlocking;
        return await;
    } else if (i == 1) {
        CoroutineScope $this$runBlocking2 = (CoroutineScope) this.L$0;
        ResultKt.throwOnFailure($result);
        return $result;
    } else {
        throw new IllegalStateException("call to 'resume' before 'invoke' with coroutine");
    }
}

@Metadata(bv = {1, 0, 3}, d1 = {"\u0000\u0012\n\u0000\n\u0002\u0010!\n\u0002\u0018\u0002\n\u0002\u0018\u0002\n\u0002\b\u0002\u0010\u0000\u001a\b\u0012\u0004\u0012\u00020\u00020\u0001*\u00020\u0003HŠ@¢\u0006\u0004\b\u0004\u0010\u0005"}, d2 = {"<anonymous>", "", "Lcom/hyfontstudio/fontspro/base/Font;", "Lkotlinx/coroutines/CoroutineScope;", "invoke", "(Ljava/lang/Object;Ljava/lang/Object;)Ljava/lang/Object;"}, k = 3, mv = {1, 1, 16})
@DebugMetadata(c = "com.hyfontstudio.fontspro.ime.core.FontService$Companion$listCoroutineScope$1$1", f = "FontService.kt", i = {}, l = {}, m = "invokeSuspend", n = {}, s = {})
/* renamed from: com.hyfontstudio.fontspro.ime.core.FontService$Companion$listCoroutineScope$1$1  reason: invalid class name */
/* compiled from: FontService.kt */
static final class AnonymousClass1 extends SuspendLambda implements Function2<CoroutineScope, Continuation<? super List<Font>>, Object> {
    int label;
    private CoroutineScope p$;

    public final Continuation<Unit> create(Object obj, Continuation<?> continuation) {
        Intrinsics.checkParameterIsNotNull(continuation, "completion");
        AnonymousClass1 r0 = new AnonymousClass1(continuation);
        CoroutineScope coroutineScope = (CoroutineScope) obj;
        r0.p$ = (CoroutineScope) obj;
        return r0;
    }

    public final Object invoke(Object obj, Object obj2) {
        return ((AnonymousClass1) create(obj, (Continuation) obj2)).invokeSuspend(Unit.INSTANCE);
    }

    public final Object invokeSuspend(Object $result) {
        IntrinsicsKt.getCOROUTINE_SUSPENDED();
        if (this.label == 0) {
            ResultKt.throwOnFailure($result);
            CoroutineScope coroutineScope = this.p$;
            StringBuilder sb = new StringBuilder();
            sb.append("Thread:::");
            Thread currentThread = Thread.currentThread();
            Intrinsics.checkExpressionValueIsNotNull(currentThread, "Thread.currentThread()");
            sb.append(currentThread.getName());
            System.out.print(sb.toString());
            return FontService.Companion.getResourcesJsonList();
        }
        throw new IllegalStateException("call to 'resume' before 'invoke' with coroutine");
    }
}
}

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