[macosx] throw exception if use input source : Wubi Xing or Stroke traditional

FULL PRODUCT VERSION :
java version "1.8.0_74"
Java(TM) SE Runtime Environment (build 1.8.0_74-b02)
Java HotSpot(TM) 64-Bit Server VM (build 25.74-b02, mixed mode)


ADDITIONAL OS VERSION INFORMATION :
Mac OSX 10.11.1

A DESCRIPTION OF THE PROBLEM :
Exception throws when I want to use some input source like Wubi Xing or Stroke Traditional.

First I launched the java application which will open a JTextPane. Then I change input source on my Mac to those mentioned above BEFORE JTextPane in my app opened and focused, and then click my app to let my app get focused (no JTextPane yet), then an Exception throws.
After JTextPane opened, no exception
Guess, the exception throws because the input source cannot found where to input.

2016-04-09 10:31:57.425 java[7081:648254] An uncaught exception was raised
2016-04-09 10:31:57.426 java[7081:648254] java.lang.NullPointerException
2016-04-09 10:31:57.430 java[7081:648254] (
0 CoreFoundation 0x00007fff954bfe32 __exceptionPreprocess + 178
1 libobjc.A.dylib 0x00007fff9c9b6dd4 objc_exception_throw + 48
2 CoreFoundation 0x00007fff954bfd79 -[NSException raise] + 9
3 JavaNativeFoundation 0x0000000116b10457 JNFCallObjectMethod + 212
4 libawt_lwawt.dylib 0x0000000118604c79 -[AWTView attributedSubstringForProposedRange:actualRange:] + 78
5 AppKit 0x00007fff90a98e25 -[NSTextInputContext(NSInputContext_WithCompletion) attributedSubstringForProposedRange:completionHandler:] + 105
6 AppKit 0x00007fff90a96413 __55-[NSTextInputContext handleTSMEvent:completionHandler:]_block_invoke708 + 113
7 AppKit 0x00007fff90a91eb2 -[NSTextInputContext tryHandleTSMEvent_attributedSubstringForProposedRange_withContext:dispatchCondition:dispatchWork:continuation:] + 101
8 AppKit 0x00007fff90a96326 __55-[NSTextInputContext handleTSMEvent:completionHandler:]_block_invoke702 + 517
9 AppKit 0x00007fff90389f2f -[NSTextInputContext handleTSMEvent:completionHandler:] + 2429
10 AppKit 0x00007fff90389546 _NSTSMEventHandler + 324
11 HIToolbox 0x00007fff8a79998e _ZL23DispatchEventToHandlersP14EventTargetRecP14OpaqueEventRefP14HandlerCallRec + 1231
12 HIToolbox 0x00007fff8a798e18 _ZL30SendEventToEventTargetInternalP14OpaqueEventRefP20OpaqueEventTargetRefP14HandlerCallRec + 404
13 HIToolbox 0x00007fff8a798c7b SendEventToEventTargetWithOptions + 43
14 HIToolbox 0x00007fff8a7ee319 SendTSMEvent_WithCompletionHandler + 417
15 HIToolbox 0x00007fff8a9a0115 __SendTextInputEvent_WithCompletionHandler_block_invoke + 586
16 HIToolbox 0x00007fff8a99e40d SendTextInputEvent_WithCompletionHandler + 1228
17 HIToolbox 0x00007fff8aa0a474 -[IMKInputSession _postEvent:completionHandler:] + 184
18 HIToolbox 0x00007fff8aa19f2a -[IMKInputSession _copyUniCharsForRange:intoBuffer:ofLength:completionHandler:] + 533
19 HIToolbox 0x00007fff8aa1a7ab -[IMKInputSession _coreAttributesFromRange:whichAttributes:completionHandler:] + 332
20 HIToolbox 0x00007fff8aa1c7f9 -[IMKInputSession attributedSubstringFromRange:completionHandler:] + 205
21 HIToolbox 0x00007fff8aa0cff5 __61-[IMKInputSession imkxpc_attributedSubstringFromRange:reply:]_block_invoke + 542
22 CoreFoundation 0x00007fff954554dc __CFRUNLOOP_IS_CALLING_OUT_TO_A_BLOCK__ + 12
23 CoreFoundation 0x00007fff95434df5 __CFRunLoopDoBlocks + 341
24 CoreFoundation 0x00007fff95434b5b __CFRunLoopRun + 2347
25 CoreFoundation 0x00007fff95433fc8 CFRunLoopRunSpecific + 296
26 HIToolbox 0x00007fff8a9f4588 -[IMKClientXPCInvocation invocationAwaitXPCReply] + 444
27 HIToolbox 0x00007fff8a9f8e2d -[IMKInputSession deactivate] + 2733
28 HIToolbox 0x00007fff8a9ad7cd IMKInputSessionDeactivate + 36
29 HIToolbox 0x00007fff8a9acce1 DeactivateInputMethodInstance + 80
30 HIToolbox 0x00007fff8a9a28de utDeactivateIMforDocument + 228
31 HIToolbox 0x00007fff8a7f3909 utDeactivateAllIM4Document + 120
32 HIToolbox 0x00007fff8a7f3481 MyDeactivateTSMDocument + 334
33 HIToolbox 0x00007fff8a7f3311 DeactivateTSMDocument + 64
34 AppKit 0x00007fff903c3422 -[NSTextInputContext deactivate] + 77
35 AppKit 0x00007fff901e6886 +[NSTextInputContext currentInputContext] + 218
36 CoreFoundation 0x00007fff9544bc9c __CFNOTIFICATIONCENTER_IS_CALLING_OUT_TO_AN_OBSERVER__ + 12
37 CoreFoundation 0x00007fff9544bc2f ___CFXRegistrationPost_block_invoke + 63
38 CoreFoundation 0x00007fff9544bba7 _CFXRegistrationPost + 407
39 CoreFoundation 0x00007fff9544b912 ___CFXNotificationPost_block_invoke + 50
40 CoreFoundation 0x00007fff954086d2 -[_CFXNotificationRegistrar find:object:observer:enumerator:] + 1922
41 CoreFoundation 0x00007fff95407925 _CFXNotificationPost + 693
42 Foundation 0x00007fff8ee320fa -[NSNotificationCenter postNotificationName:object:userInfo:] + 66
43 AppKit 0x00007fff90370cd3 -[NSApplication sendEvent:] + 7064
44 libosxapp.dylib 0x00000001186b632c -[NSApplicationAWT sendEvent:] + 378
45 AppKit 0x00007fff901d6d9a -[NSApplication run] + 796
46 libosxapp.dylib 0x00000001186b614d +[NSApplicationAWT runAWTLoopWithApp:] + 156
47 libawt_lwawt.dylib 0x000000011864355b -[AWTStarter starter:] + 905
48 Foundation 0x00007fff8eea241e __NSThreadPerformPerform + 279
49 CoreFoundation 0x00007fff954558b1 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ + 17
50 CoreFoundation 0x00007fff954350ac __CFRunLoopDoSources0 + 556
51 CoreFoundation 0x00007fff954345cf __CFRunLoopRun + 927
52 CoreFoundation 0x00007fff95433fc8 CFRunLoopRunSpecific + 296
53 java 0x00000001026d8463 CreateExecutionEnvironment + 871
54 java 0x00000001026d41ac JLI_Launch + 1952
55 java 0x00000001026da4c0 main + 101
56 java 0x00000001026d3a04 start + 52


STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
as described in Description


REPRODUCIBILITY :
This bug can be reproduced always.