問題分析
檔案未找到或無許可權時拋出此類異常。
解決方案
檔案未找到或無許可權時，請確認檔案路徑檔案存在，添加所需存取權限，確保檔案存在的情況下進行讀寫，並增加try catch塊做異常處理。
程式碼範例
增加讀寫外部儲存上的檔案許可權：
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"></uses-permission>
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"></uses-permission>建立檔案，增加讀寫權限並catch exception。
File extDir = Environment.getExternalStorageDirectory();
String filename = "file.txt";
File fullFilename = new File(extDir, filename);
try {
if(!fullFilename.exists()){
fullFilename.createNewFile();
fullFilename.setWritable(Boolean.TRUE);
// 寫檔案操作
}
else{
// 讀檔案操作
}
} catch (IOException e) {
e.printStackTrace();
}樣本：
java.io.FileNotFoundException: /proc/stprof/status: open failed: ENOENT (No such file or directory)
at libcore.io.IoBridge.open(IoBridge.java:496)
at java.io.FileInputStream.<init>(FileInputStream.java:76)
at java.io.FileInputStream.<init>(FileInputStream.java:103)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1494)
at android.os.Handler.dispatchMessage(Handler.java:111)
at android.os.Looper.loop(Looper.java:194)
at android.app.ActivityThread.main(ActivityThread.java:5692)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:959)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:754)
Caused by: android.system.ErrnoException: open failed: ENOENT (No such file or directory)
at libcore.io.Posix.open(Native Method)
at libcore.io.BlockGuardOs.open(BlockGuardOs.java:186)
at libcore.io.IoBridge.open(IoBridge.java:482)
... 10 more異常導致應用無法啟動。日誌如下：
10-20 09:43:08.073 820 820 E WifiTrafficPoller: TRAFFIC_STATS_POLL true Token 1138 num clients 12
10-20 09:43:08.074 820 820 E WifiTrafficPoller: packet count Tx=237196 Rx=493756
10-20 09:43:08.365 820 842 W BroadcastQueue: Skipping deliver [background] BroadcastRecord{9a089ad u-1 android.net.conn.CONNECTIVITY_CHANGE} to ReceiverList{2c1b84e2 23189 (unknown name)/2000/u-1 remote:2663fdd7}: process crashing
10-20 09:43:08.401 23079 23079 E ActivityThread: mtprof entry can not be found
10-20 09:43:08.401 23079 23079 E ActivityThread: java.io.FileNotFoundException: /proc/mtprof/status: open failed: ENOENT (No such file or directory)
10-20 09:43:08.401 23079 23079 E ActivityThread: at libcore.io.IoBridge.open(IoBridge.java:496)
10-20 09:43:08.401 23079 23079 E ActivityThread: at java.io.FileInputStream.<init>(FileInputStream.java:76)
10-20 09:43:08.401 23079 23079 E ActivityThread: at java.io.FileInputStream.<init>(FileInputStream.java:103)
10-20 09:43:08.401 23079 23079 E ActivityThread: at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1494)
10-20 09:43:08.401 23079 23079 E ActivityThread: at android.os.Handler.dispatchMessage(Handler.java:111)
10-20 09:43:08.401 23079 23079 E ActivityThread: at android.os.Looper.loop(Looper.java:194)
10-20 09:43:08.401 23079 23079 E ActivityThread: at android.app.ActivityThread.main(ActivityThread.java:5692)
10-20 09:43:08.401 23079 23079 E ActivityThread: at java.lang.reflect.Method.invoke(Native Method)
10-20 09:43:08.401 23079 23079 E ActivityThread: at java.lang.reflect.Method.invoke(Method.java:372)
10-20 09:43:08.401 23079 23079 E ActivityThread: at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:959)
10-20 09:43:08.401 23079 23079 E ActivityThread: at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:754)
10-20 09:43:08.401 23079 23079 E ActivityThread: Caused by: android.system.ErrnoException: open failed: ENOENT (No such file or directory)
10-20 09:43:08.401 23079 23079 E ActivityThread: at libcore.io.Posix.open(Native Method)
10-20 09:43:08.401 23079 23079 E ActivityThread: at libcore.io.BlockGuardOs.open(BlockGuardOs.java:186)
10-20 09:43:08.401 23079 23079 E ActivityThread: at libcore.io.IoBridge.open(IoBridge.java:482)
10-20 09:43:08.401 23079 23079 E ActivityThread: ... 10 more
10-20 09:43:08.415 23079 23079 W Launcher: setApplicationContext called twice!
10-20 09:43:08.422 23079 23079 E Fatal exception: :java.lang.RuntimeException: Unable to start activity ComponentInfo{}: java.io.IOException: broken file descriptor
10-20 09:43:08.422 23079 23079 W System.err: java.lang.RuntimeException: Unable to start activity ComponentInfo{}: java.io.IOException: broken file descriptor
10-20 09:43:08.422 23079 23079 W System.err: at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2581)
10-20 09:43:08.422 23079 23079 W System.err: at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2656)
10-20 09:43:08.422 23079 23079 W System.err: at android.app.ActivityThread.access$800(ActivityThread.java:178)
10-20 09:43:08.423 23079 23079 W System.err: at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1512)
10-20 09:43:08.423 23079 23079 W System.err: at android.os.Handler.dispatchMessage(Handler.java:111)
10-20 09:43:08.423 23079 23079 W System.err: at android.os.Looper.loop(Looper.java:194)
10-20 09:43:08.423 23079 23079 W System.err: at android.app.ActivityThread.main(ActivityThread.java:5692)
10-20 09:43:08.423 23079 23079 W System.err: at java.lang.reflect.Method.invoke(Native Method)
10-20 09:43:08.423 23079 23079 W System.err: at java.lang.reflect.Method.invoke(Method.java:372)
10-20 09:43:08.423 23079 23079 W System.err: at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:959)
10-20 09:43:08.423 23079 23079 W System.err: at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:754)
10-20 09:43:08.423 23079 23079 W System.err: Caused by: java.io.IOException: broken file descriptor
10-20 09:43:08.423 23079 23079 W System.err: at android.graphics.BitmapFactory.nativeDecodeFileDescriptor(Native Method)
10-20 09:43:08.423 23079 23079 W System.err: at android.graphics.BitmapFactory.decodeFileDescriptor(BitmapFactory.java:714)
10-20 09:43:08.423 23079 23079 W System.err: at android.app.WallpaperManager$Globals.getCurrentWallpaperLocked(WallpaperManager.java:308)
10-20 09:43:08.423 23079 23079 W System.err: at android.app.WallpaperManager$Globals.peekWallpaperBitmap(WallpaperManager.java:270)
10-20 09:43:08.423 23079 23079 W System.err: at android.app.WallpaperManager.getDrawable(WallpaperManager.java:413)更換手機案頭應用布局介面時調用native方法decodeFileDescriptor讀取檔案/proc/stprof/status拋出了異常未捕獲導致進程崩潰，建議按照樣本一判斷檔案是否存在並對異常進行捕獲處理。