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Kotlin 协程异步任务工具类：高效处理异步操作与超时控制

news 2025/9/2 8:36:03

下面是完整的 Kotlin 协程异步任务工具类代码，包含详细注释和使用示例。

import kotlinx.coroutines.*
import kotlin.coroutines.CoroutineContext/*** 异步任务回调接口* 提供任务执行的各种状态回调** @param T 任务返回结果的类型*/
interface TaskCallback<T> {/*** 任务执行成功回调* @param result 任务执行结果*/fun onSuccess(result: T)/*** 任务执行失败回调* @param error 异常信息*/fun onFailure(error: Throwable)/*** 任务执行超时回调*/fun onTimeout()/*** 任务被取消回调*/fun onCancelled()
}/*** Kotlin 协程异步任务工具类* 提供强大的异步任务执行能力，支持超时控制、重试机制、并行执行等功能*/
class CoroutineTaskUtil private constructor() : CoroutineScope {// 使用 SupervisorJob 允许子协程独立失败而不影响其他协程private val job = SupervisorJob()// 协程上下文配置override val coroutineContext: CoroutineContextget() = Dispatchers.Default + job + CoroutineExceptionHandler { _, throwable ->println("未捕获的协程异常: ${throwable.message}")}companion object {@Volatileprivate var instance: CoroutineTaskUtil? = null/*** 获取工具类单例实例* @return CoroutineTaskUtil 实例*/fun getInstance(): CoroutineTaskUtil {return instance ?: synchronized(this) {instance ?: CoroutineTaskUtil().also { instance = it }}}}/*** 执行异步任务（支持超时控制）** @param task 要执行的挂起任务* @param timeoutMs 超时时间（毫秒），null 表示不设置超时* @param callback 回调接口* @return Job 对象，可用于取消任务*/fun <T> executeWithTimeout(task: suspend () -> T,timeoutMs: Long? = null,callback: TaskCallback<T>? = null): Job {return launch {try {val result = if (timeoutMs != null) {withTimeout(timeoutMs) { task() }} else {task()}callback?.onSuccess(result)} catch (e: TimeoutCancellationException) {callback?.onTimeout()} catch (e: CancellationException) {callback?.onCancelled()} catch (e: Exception) {callback?.onFailure(e)}}}/*** 执行异步任务（简化版，不带超时）** @param task 要执行的挂起任务* @param callback 回调接口* @return Job 对象，可用于取消任务*/fun <T> execute(task: suspend () -> T,callback: TaskCallback<T>? = null): Job {return executeWithTimeout(task, null, callback)}/*** 在IO线程执行任务，在主线程回调** @param task 要执行的挂起任务* @param callback 回调接口* @return Job 对象，可用于取消任务*/fun <T> executeOnIoWithMainCallback(task: suspend () -> T,callback: TaskCallback<T>? = null): Job {return CoroutineScope(Dispatchers.IO).launch {try {val result = task()withContext(Dispatchers.Main) {callback?.onSuccess(result)}} catch (e: Exception) {withContext(Dispatchers.Main) {when (e) {is CancellationException -> callback?.onCancelled()else -> callback?.onFailure(e)}}}}}/*** 执行多个并行任务，等待所有任务完成** @param tasks 要执行的多个任务* @param callback 回调接口* @return Job 对象，可用于取消任务*/fun <T> executeAll(vararg tasks: suspend () -> T,callback: TaskCallback<List<T>>? = null): Job {return launch {try {val deferredResults = tasks.map { async { it() } }val results = deferredResults.awaitAll()callback?.onSuccess(results)} catch (e: Exception) {callback?.onFailure(e)}}}/*** 执行带重试机制的任务** @param task 要执行的任务* @param retries 重试次数* @param delayMs 重试间隔（毫秒）* @param callback 回调接口* @return Job 对象，可用于取消任务*/fun <T> executeWithRetry(task: suspend () -> T,retries: Int = 3,delayMs: Long = 1000,callback: TaskCallback<T>? = null): Job {return launch {var currentRetry = 0var lastError: Throwable? = nullwhile (currentRetry <= retries) {try {val result = task()callback?.onSuccess(result)return@launch} catch (e: Exception) {lastError = ecurrentRetry++if (currentRetry > retries) breakdelay(delayMs)}}callback?.onFailure(lastError ?: Exception("在 $retries 次重试后仍失败"))}}/*** 取消所有正在执行的任务*/fun cancelAll() {job.cancel("手动取消所有任务")}/*** 关闭工具类，释放资源*/fun shutdown() {cancelAll()}
}/*** 简化使用的顶层扩展函数*//*** 为任意类型添加异步执行能力*/
suspend fun <T> T.executeAsync(timeoutMs: Long? = null,callback: TaskCallback<T>? = null
): Job {return CoroutineTaskUtil.getInstance().executeWithTimeout(task = { this },timeoutMs = timeoutMs,callback = callback)
}/*** 简化版的异步任务执行函数*/
suspend fun <T> executeTask(timeoutMs: Long? = null,task: suspend () -> T,onSuccess: (T) -> Unit = {},onFailure: (Throwable) -> Unit = {},onTimeout: () -> Unit = {},onCancelled: () -> Unit = {}
): Job {return CoroutineTaskUtil.getInstance().executeWithTimeout(task = task,timeoutMs = timeoutMs,callback = object : TaskCallback<T> {override fun onSuccess(result: T) = onSuccess(result)override fun onFailure(error: Throwable) = onFailure(error)override fun onTimeout() = onTimeout()override fun onCancelled() = onCancelled()})
}// ==================================================
// 使用示例
// ==================================================/*** 工具类使用示例*/
class CoroutineTaskExamples {/*** 示例1：基本用法*/fun exampleBasicUsage() {CoroutineTaskUtil.getInstance().execute(task = {delay(1000)"异步任务完成"},callback = object : TaskCallback<String> {override fun onSuccess(result: String) {println("任务成功: $result")}override fun onFailure(error: Throwable) {println("任务失败: ${error.message}")}override fun onTimeout() {println("任务超时")}override fun onCancelled() {println("任务被取消")}})}/*** 示例2：带超时的任务*/fun exampleWithTimeout() {CoroutineTaskUtil.getInstance().executeWithTimeout(task = {delay(5000)"长时间任务完成"},timeoutMs = 3000,callback = object : TaskCallback<String> {override fun onSuccess(result: String) {println("成功: $result")}override fun onFailure(error: Throwable) {println("失败: ${error.message}")}override fun onTimeout() {println("任务超时，已中断")}override fun onCancelled() {println("任务被取消")}})}/*** 示例3：带重试的任务*/fun exampleWithRetry() {var attemptCount = 0CoroutineTaskUtil.getInstance().executeWithRetry(task = {attemptCount++if (attemptCount < 3) {throw RuntimeException("第${attemptCount}次尝试失败")}"第${attemptCount}次尝试成功"},retries = 5,delayMs = 500,callback = object : TaskCallback<String> {override fun onSuccess(result: String) {println("重试成功: $result")}override fun onFailure(error: Throwable) {println("重试失败: ${error.message}")}override fun onTimeout() {}override fun onCancelled() {}})}/*** 示例4：并行执行多个任务*/fun exampleParallelTasks() {CoroutineTaskUtil.getInstance().executeAll({ delay(1000)"任务1结果" },{ delay(2000)"任务2结果" },{ delay(1500)"任务3结果" },callback = object : TaskCallback<List<String>> {override fun onSuccess(result: List<String>) {println("所有任务完成: $result")}override fun onFailure(error: Throwable) {println("任务执行失败: ${error.message}")}override fun onTimeout() {}override fun onCancelled() {}})}/*** 示例5：使用简化API*/suspend fun exampleSimplifiedAPI() {executeTask(timeoutMs = 5000,task = {delay(2000)"简化API示例结果"},onSuccess = { result ->println("简化API成功: $result")},onFailure = { error ->println("简化API失败: ${error.message}")})}
}/*** 实际应用场景示例*/
class PracticalExamples {/*** 场景1：网络请求处理*/fun fetchUserData(userId: String) {CoroutineTaskUtil.getInstance().executeWithTimeout(task = {// 模拟网络请求delay(2000)"用户${userId}的数据"},timeoutMs = 10000,callback = object : TaskCallback<String> {override fun onSuccess(result: String) {updateUserInterface(result)}override fun onFailure(error: Throwable) {showErrorMessage("数据加载失败")}override fun onTimeout() {showErrorMessage("请求超时，请重试")}override fun onCancelled() {showErrorMessage("请求被取消")}})}private fun updateUserInterface(data: String) {println("更新UI: $data")}private fun showErrorMessage(message: String) {println("错误信息: $message")}/*** 场景2：文件操作*/fun processLargeFile(filePath: String) {CoroutineTaskUtil.getInstance().executeOnIoWithMainCallback(task = {readAndProcessFile(filePath)},callback = object : TaskCallback<String> {override fun onSuccess(result: String) {showProcessingResult(result)}override fun onFailure(error: Throwable) {showErrorMessage("文件处理失败: ${error.message}")}override fun onTimeout() {}override fun onCancelled() {}})}private suspend fun readAndProcessFile(filePath: String): String {delay(3000)return "处理完成的文件内容: $filePath"}private fun showProcessingResult(result: String) {println("处理结果: $result")}
}// 测试代码
fun main() = runBlocking {val examples = CoroutineTaskExamples()println("=== 示例1：基本用法 ===")examples.exampleBasicUsage()delay(1500)println("\n=== 示例2：带超时的任务 ===")examples.exampleWithTimeout()delay(4000)println("\n=== 示例3：带重试的任务 ===")examples.exampleWithRetry()delay(3000)println("\n=== 示例4：并行执行多个任务 ===")examples.exampleParallelTasks()delay(3000)println("\n=== 示例5：使用简化API ===")examples.exampleSimplifiedAPI()delay(3000)println("\n=== 实际应用场景 ===")val practicalExamples = PracticalExamples()practicalExamples.fetchUserData("123")delay(3000)practicalExamples.processLargeFile("/path/to/file.txt")delay(4000)
}