SpeedCalculator.endTask()触发了NullPointerException

[miraclehen]

OkDownload Version

v1.0.3

问题描述

hello。在我项目中，我用OkDownload去下载十多个问题，并且是并行下载，最大并行数为2。我在使用这个库的时候遇到一些问题，当我调用DownloadTask.Cancel()函数时，会触发一个NullPointerException异常。我使用的是监听器为DownloadListener4WithSpeed。

日志

java.lang.NullPointerException: Attempt to invoke virtual method 'void com.liulishuo.okdownload.SpeedCalculator.endTask()' on a null object reference
                                                                   at com.liulishuo.okdownload.core.listener.assist.Listener4SpeedAssistExtend.dispatchTaskEnd(Listener4SpeedAssistExtend.java:85)
                                                                   at com.liulishuo.okdownload.core.listener.assist.Listener4Assist.taskEnd(Listener4Assist.java:104)
                                                                   at com.liulishuo.okdownload.core.listener.DownloadListener4.taskEnd(DownloadListener4.java:116)
                                                                   at com.liulishuo.okdownload.core.listener.DownloadListenerBunch.taskEnd(DownloadListenerBunch.java:115)
                                                                   at com.liulishuo.okdownload.core.dispatcher.CallbackDispatcher$DefaultTransmitListener$11.run(CallbackDispatcher.java:367)
                                                                   at android.os.Handler.handleCallback(Handler.java:751)
                                                                   at android.os.Handler.dispatchMessage(Handler.java:95)
                                                                   at android.os.Looper.loop(Looper.java:154)
                                                                   at android.app.ActivityThread.main(ActivityThread.java:6119)
                                                                   at java.lang.reflect.Method.invoke(Native Method)
                                                                   at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:886)
                                                                   at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:776)

[miraclehen]

我尝试把okdownload的sample中的队列下载，替换成DownloadListener4WithSpeed，然后开启并行下载，最后点击全部删除按钮。也会触发这个异常。

[SunJenry]

@miraclehen 遇到了同样的问题，如果最大并行数是2，那么在同时下载2个任务时，再打开第三个新的任务，然后在前两个任务没有完成时调用第三个任务的cancel方法就会触发这个问题。监听器同样是DownloadListener4WithSpeed，Log也相同。

[mouness2020]

yes please fix the problem
cancelling waiting task make app crash

Fatal Exception: java.lang.NullPointerException: Attempt to invoke virtual method 'void com.liulishuo.okdownload.SpeedCalculator.endTask()' on a null object reference
at com.liulishuo.okdownload.core.listener.assist.Listener4SpeedAssistExtend.dispatchTaskEnd(Listener4SpeedAssistExtend.java:85)
at com.liulishuo.okdownload.core.listener.assist.Listener4Assist.taskEnd(Listener4Assist.java:104)
at com.liulishuo.okdownload.core.listener.DownloadListener4.taskEnd(DownloadListener4.java:116)
at com.liulishuo.okdownload.core.dispatcher.CallbackDispatcher$DefaultTransmitListener$11.run(CallbackDispatcher.java:367)
at android.os.Handler.handleCallback(Handler.java:789)
at android.os.Handler.dispatchMessage(Handler.java:98)
at android.os.Looper.loop(Looper.java:164)
at android.app.ActivityThread.main(ActivityThread.java:6938)
at java.lang.reflect.Method.invoke(Method.java)
at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:327)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1374)

[kslr]

同样有该问题

Family | PGN528
Model | PGN528 (NRD90M)
Architecture | armeabi-v7a
Battery Level | 44%
Orientation | portrait
Memory | Total: 1.8 GB / Free: 426.6 MB
Capacity | Total: 10.1 GB / Free: 2.7 GB
Simulator | false
brand | condor
charging | true
low_memory | false
manufacturer | SPA Condor Electronics
online | true
screen_density | 2
screen_dpi | 320
screen_resolution | 1280x720

Version | 7.0 (PGN528)
Kernel Version | Linux version 3.18.35 (android@COMPILER-22) (gcc version 4.9 20150123 (prerelease) (GCC) ) #1 SMP PREEMPT Tue Oct 10 19:03:24 CST 2017
Rooted | yes

java.lang.NullPointerException: Attempt to invoke virtual method 'void com.liulishuo.okdownload.SpeedCalculator.endTask()' on a null object reference
    at com.liulishuo.okdownload.core.listener.assist.Listener4SpeedAssistExtend.dispatchTaskEnd(Listener4SpeedAssistExtend.java:85)
    at com.liulishuo.okdownload.core.listener.assist.Listener4Assist.taskEnd(Listener4Assist.java:104)
    at com.liulishuo.okdownload.core.listener.DownloadListener4.taskEnd(DownloadListener4.java:116)
    at com.liulishuo.okdownload.UnifiedListenerManager$1.taskEnd(UnifiedListenerManager.java:271)
    at com.liulishuo.okdownload.core.dispatcher.CallbackDispatcher$DefaultTransmitListener.taskEnd(CallbackDispatcher.java:371)
    at com.liulishuo.okdownload.core.dispatcher.DownloadDispatcher.inspectForConflict(DownloadDispatcher.java:492)
    at com.liulishuo.okdownload.core.dispatcher.DownloadDispatcher.inspectForConflict(DownloadDispatcher.java:427)
    at com.liulishuo.okdownload.core.dispatcher.DownloadDispatcher.inspectForConflict(DownloadDispatcher.java:420)
    at com.liulishuo.okdownload.core.dispatcher.DownloadDispatcher.enqueueLocked(DownloadDispatcher.java:153)
    at com.liulishuo.okdownload.core.dispatcher.DownloadDispatcher.enqueue(DownloadDispatcher.java:113)
    at com.liulishuo.okdownload.DownloadTask.enqueue(DownloadTask.java:515)
    at com.liulishuo.okdownload.UnifiedListenerManager.enqueueTaskWithUnifiedListener(UnifiedListenerManager.java:121)
    at com.loadbt.loadbt.MainActivity$GlobalTaskManager.enqueueTask(MainActivity.java:233)
    at com.loadbt.loadbt.MainActivity$1.onDownloadStart(MainActivity.java:176)
    at xf.a(SourceFile:547)
    at afs.handleMessage(SourceFile:25)
    at android.os.Handler.dispatchMessage(Handler.java:110)
    at android.os.Looper.loop(Looper.java:203)
    at android.app.ActivityThread.main(ActivityThread.java:6269)
    at java.lang.reflect.Method.invoke(Method.java)
    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1063)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:924)

[xueshukai]

同样的问题。。。