java.lang.ArrayIndexOutOfBoundsException

[tianxiaogu]

Reproduced in Android Studio Emulator and Android Nexus 5 Phone (6.0.1)

Steps:

1. Install v1.4 from FDroid.
2. Launch app.
3. Disable automatically refresh
4. Change server address to an invalid one, e.g., xxyyzz.
5. Click refresh.

Solution:
At FlashManager.java#L184, min may be 0 and the array may be empty.
Hence, we need to handle this case explicitly.

FlashManager.java#L184

---

Stack traces

11-01 14:56:58.359 12058 12058 I System.out: LibreNews Debug: Unable to load flashes from storage: No flash storage file exists or is empty.
11-01 14:56:58.360 12058 12058 W System.err: java.io.FileNotFoundException: No flash storage file exists or is empty.
11-01 14:56:58.360 12058 12058 W System.err:    at app.librenews.io.librenews.controllers.FlashManager.loadFlashesFromStorage(FlashManager.java:140)
11-01 14:56:58.360 12058 12058 W System.err:    at app.librenews.io.librenews.controllers.FlashManager.getLatestPushedFlashes(FlashManager.java:191)
11-01 14:56:58.360 12058 12058 W System.err:    at app.librenews.io.librenews.controllers.FlashManager.refresh(FlashManager.java:251)
11-01 14:56:58.360 12058 12058 W System.err:    at app.librenews.io.librenews.views.MainFlashActivity$1.onClick(MainFlashActivity.java:67)
11-01 14:56:58.360 12058 12058 W System.err:    at android.view.View.performClick(View.java:5204)
11-01 14:56:58.360 12058 12058 W System.err:    at android.view.View$PerformClick.run(View.java:21153)
11-01 14:56:58.360 12058 12058 W System.err:    at android.os.Handler.handleCallback(Handler.java:739)
11-01 14:56:58.360 12058 12058 W System.err:    at android.os.Handler.dispatchMessage(Handler.java:95)
11-01 14:56:58.360 12058 12058 W System.err:    at android.os.Looper.loop(Looper.java:148)
11-01 14:56:58.360 12058 12058 W System.err:    at android.app.ActivityThread.main(ActivityThread.java:5417)
11-01 14:56:58.360 12058 12058 W System.err:    at java.lang.reflect.Method.invoke(Native Method)
11-01 14:56:58.360 12058 12058 W System.err:    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)
11-01 14:56:58.360 12058 12058 W System.err:    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)

// CRASH: app.librenews.io.librenews (pid 3182) (elapsed nanos: 493838390542)
// Short Msg: java.lang.ArrayIndexOutOfBoundsException
// Long Msg: java.lang.ArrayIndexOutOfBoundsException: length=0; index=0
// Build Label: Android/sdk_google_phone_x86/generic_x86:6.0/MASTER/4088240:userdebug/test-keys
// Build Changelist: 4088240
// Build Time: 1497047463000
// java.lang.ArrayIndexOutOfBoundsException: length=0; index=0
// 	at app.librenews.io.librenews.controllers.FlashManager.convertFlashesToOutputString(FlashManager.java:184)
// 	at app.librenews.io.librenews.controllers.FlashManager.writeFlashesToStorage(FlashManager.java:152)
// 	at app.librenews.io.librenews.controllers.FlashManager.clearPushedFlashes(FlashManager.java:200)
// 	at app.librenews.io.librenews.controllers.FlashManager.refresh(FlashManager.java:256)
// 	at app.librenews.io.librenews.views.MainFlashActivity$1.onClick(MainFlashActivity.java:67)
// 	at android.view.View.performClick(View.java:5198)
// 	at android.view.View$PerformClick.run(View.java:21147)
// 	at android.os.Handler.handleCallback(Handler.java:739)
// 	at android.os.Handler.dispatchMessage(Handler.java:95)
// 	at android.os.Looper.loop(Looper.java:148)
// 	at android.app.ActivityThread.main(ActivityThread.java:5417)
// 	at java.lang.reflect.Method.invoke(Native Method)
// 	at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)
// 	at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)
// 

[Ran-Li-007]

I think one possible solution of this is just deleting the three line, FlashManager.java#L180 to FlashManager.java#L182, that will prevent program running to the following loop in line 183.