編輯：關於Android編程
首先交代下問題背景，前些日子自己在android上搞了個入侵檢測玩。就是camera當作監控設備，每隔一定時間檢測是否有東西入侵，如果入侵率到一定程度就報警的東西。最近發現，每次運行超過20分鐘，app直接掛掉消失。下面附上核心完整log:
01-01 21:17:42.321 I/yan ( 2588): /storage/sdcard0/InvadeDetect/ 1111111111111 01-01 21:17:42.650 E/PowerManagerService( 501): (GYP)enter sleep check_in_PowerMonitorHandler,mScreenIsOff=true;mScreenIsSwitchToOn=false mRequestSleepCount=4 mScreenOffTime=514309 01-01 21:17:43.008 D/NvOsDebugPrintf( 163): NvCamGrinder HAL_camera_device_enable_msg_type 3 01-01 21:17:43.008 D/NvOsDebugPrintf( 163): NvCamGrinder HAL_camera_device_enable_msg_type 3 01-01 21:17:43.057 I/dalvikvm-heap( 2588): Grow heap (frag case) to 18.527MB for 1228816-byte allocation 01-01 21:17:43.057 W/dalvikvm( 2588): JNI: pin count on array 0x410f1fd8 ([I) is now 1019 01-01 21:17:43.063 W/dalvikvm( 2588): JNI: pin count on array 0x410f1fd8 ([I) is now 1019 01-01 21:17:43.066 D/dalvikvm( 2588): GC_CONCURRENT freed 5780K, 45% free 7740K/14060K, paused 2ms+2ms, total 9ms 01-01 21:17:43.324 W/dalvikvm( 2588): ReferenceTable overflow (max=1024) 01-01 21:17:43.324 W/dalvikvm( 2588): JNI pinned array reference table (0x5d4440a8) dump: 01-01 21:17:43.324 W/dalvikvm( 2588): Last 10 entries (of 1024): 01-01 21:17:43.324 W/dalvikvm( 2588): 1023: 0x410f1f70 char[] (3 elements) 01-01 21:17:43.324 W/dalvikvm( 2588): 1022: 0x40c622e8 char[] (1 elements) 01-01 21:17:43.325 W/dalvikvm( 2588): 1021: 0x40c62268 char[] (1 elements) 01-01 21:17:43.325 W/dalvikvm( 2588): 1020: 0x40c61648 char[] (1 elements) 01-01 21:17:43.325 W/dalvikvm( 2588): 1019: 0x40e28ab8 char[] (5 elements) 01-01 21:17:43.325 W/dalvikvm( 2588): 1018: 0x410f1fd8 int[] (307200 elements) 01-01 21:17:43.325 W/dalvikvm( 2588): 1017: 0x410f1fd8 int[] (307200 elements) 01-01 21:17:43.325 W/dalvikvm( 2588): 1016: 0x410f1fd8 int[] (307200 elements) 01-01 21:17:43.325 W/dalvikvm( 2588): 1015: 0x410f1fd8 int[] (307200 elements) 01-01 21:17:43.325 W/dalvikvm( 2588): 1014: 0x410f1fd8 int[] (307200 elements) 01-01 21:17:43.325 W/dalvikvm( 2588): Summary: 01-01 21:17:43.326 W/dalvikvm( 2588): 3 of char[] (1 elements) (3 unique instances) 01-01 21:17:43.326 W/dalvikvm( 2588): 1 of char[] (3 elements) 01-01 21:17:43.326 W/dalvikvm( 2588): 1 of char[] (5 elements) 01-01 21:17:43.326 W/dalvikvm( 2588): 1019 of int[] (307200 elements) (1 unique instances) 01-01 21:17:43.326 E/dalvikvm( 2588): Failed adding to JNI pinned array ref table (1024 entries) 01-01 21:17:43.326 I/dalvikvm( 2588): "Thread-183" prio=5 tid=14 RUNNABLE 01-01 21:17:43.326 I/dalvikvm( 2588): | group="main" sCount=0 dsCount=0 obj=0x40f89e08 self=0x5a6ca710 01-01 21:17:43.327 I/dalvikvm( 2588): | sysTid=3823 nice=0 sched=0/0 cgrp=apps handle=1517075840 01-01 21:17:43.327 I/dalvikvm( 2588): | state=R schedstat=( 967539651465 45738384690 224828 ) utm=95515 stm=1238 core=2 01-01 21:17:43.327 I/dalvikvm( 2588): at libcore.icu.NativeDecimalFormat.open(Native Method) 01-01 21:17:43.327 I/dalvikvm( 2588): at libcore.icu.NativeDecimalFormat.(NativeDecimalFormat.java:123) 01-01 21:17:43.327 I/dalvikvm( 2588): at java.text.DecimalFormat.initNative(DecimalFormat.java:556) 01-01 21:17:43.327 I/dalvikvm( 2588): at java.text.DecimalFormat. (DecimalFormat.java:551) 01-01 21:17:43.327 I/dalvikvm( 2588): at java.text.DecimalFormat. (DecimalFormat.java:529) 01-01 21:17:43.328 I/dalvikvm( 2588): at org.mo.invadedetect.CameraActivity.getRate(CameraActivity.java:513) 01-01 21:17:43.328 I/dalvikvm( 2588): at org.mo.invadedetect.CameraActivity$CheckProcessThread.run(CameraActivity.java:402) 01-01 21:17:43.328 I/dalvikvm( 2588): 01-01 21:17:43.328 E/dalvikvm( 2588): VM aborting 01-01 21:17:43.328 F/libc ( 2588): Fatal signal 11 (SIGSEGV) at 0xdeadd00d (code=1), thread 3823 (Thread-183) 01-01 21:17:43.430 I/DEBUG ( 157): *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** 01-01 21:17:43.430 I/DEBUG ( 157): Build fingerprint: 'generic/pluto/pluto:4.2.2/JDQ39/eng.ztetd.20131210.002516:eng/release-keys' 01-01 21:17:43.430 I/DEBUG ( 157): Revision: '0' 01-01 21:17:43.431 I/DEBUG ( 157): pid: 2588, tid: 3823, name: Thread-183 >>> org.mo.invadedetect <<< 01-01 21:17:43.431 I/DEBUG ( 157): signal 11 (SIGSEGV), code 1 (SEGV_MAPERR), fault addr deadd00d 01-01 21:17:43.553 I/DEBUG ( 157): r0 00000000 r1 00000000 r2 deadd00d r3 00000000 01-01 21:17:43.553 I/DEBUG ( 157): r4 4081cb58 r5 0000020c r6 00000000 r7 4081cec0 01-01 21:17:43.553 I/DEBUG ( 157): r8 5c775c54 r9 5c675e38 sl 5a6ca720 fp 5c775c6c 01-01 21:17:43.553 I/DEBUG ( 157): ip 00004000 sp 5c775598 lr 4004f3f9 pc 407a927c cpsr 600b0030 01-01 21:17:43.554 I/DEBUG ( 157): d0 74726f6261204d56 d1 6a2e79746976696e 01-01 21:17:43.554 I/DEBUG ( 157): d2 656d61432e746375 d3 697669746341616c 01-01 21:17:43.554 I/DEBUG ( 157): d4 7fefffffffffffff d5 7fefffffffffffff 01-01 21:17:43.554 I/DEBUG ( 157): d6 c7efffffe0000000 d7 0000000000000000 01-01 21:17:43.555 I/DEBUG ( 157): d8 3e6041893a83126f d9 c0100000ffffffff 01-01 21:17:43.555 I/DEBUG ( 157): d10 bff3441350a65936 d11 3fd34413509f79fe 01-01 21:17:43.555 I/DEBUG ( 157): d12 3ddb7cdfd9d7bdbb d13 0000000000000000 01-01 21:17:43.555 I/DEBUG ( 157): d14 0000000000000000 d15 0000000000000000 01-01 21:17:43.555 I/DEBUG ( 157): d16 0000000000000000 d17 4330000000000000 01-01 21:17:43.555 I/DEBUG ( 157): d18 3fb0000000000000 d19 fffc0000fffc0000 01-01 21:17:43.555 I/DEBUG ( 157): d20 0000000300000004 d21 0000000100000002 01-01 21:17:43.556 I/DEBUG ( 157): d22 0707070703030303 d23 0000027f0000027f 01-01 21:17:43.556 I/DEBUG ( 157): d24 fffe0000ffff0000 d25 fffc0000fffd0000 01-01 21:17:43.556 I/DEBUG ( 157): d26 0000028000000280 d27 0000028000000280 01-01 21:17:43.556 I/DEBUG ( 157): d28 0000000200000003 d29 0000000000000001 01-01 21:17:43.556 I/DEBUG ( 157): d30 0000000000000000 d31 0000000000000000 01-01 21:17:43.557 I/DEBUG ( 157): scr 60000013 01-01 21:17:43.561 I/DEBUG ( 157): 01-01 21:17:43.561 I/DEBUG ( 157): backtrace: 01-01 21:17:43.562 I/DEBUG ( 157): #00 pc 0004527c /system/lib/libdvm.so (dvmAbort+75) 01-01 21:17:43.562 I/DEBUG ( 157): #01 pc 00048499 /system/lib/libdvm.so 01-01 21:17:43.562 I/DEBUG ( 157): #02 pc 0004a7e5 /system/lib/libdvm.so 01-01 21:17:43.562 I/DEBUG ( 157): #03 pc 0003b87f /system/lib/libdvm.so 01-01 21:17:43.562 I/DEBUG ( 157): #04 pc 00016117 /system/lib/libjavacore.so 01-01 21:17:43.562 I/DEBUG ( 157): #05 pc 00019471 /system/lib/libjavacore.so 01-01 21:17:43.563 I/DEBUG ( 157): #06 pc 0001979b /system/lib/libjavacore.so 01-01 21:17:43.563 I/DEBUG ( 157): #07 pc 0001d850 /system/lib/libdvm.so (dvmPlatformInvoke+112) 01-01 21:17:43.563 I/DEBUG ( 157): #08 pc 0004ca1d /system/lib/libdvm.so (dvmCallJNIMethod(unsigned int const*, JValue*, Method const*, Thread*)+396) 01-01 21:17:43.563 I/DEBUG ( 157): #09 pc 000381d5 /system/lib/libdvm.so (dvmCheckCallJNIMethod(unsigned int const*, JValue*, Method const*, Thread*)+8) 01-01 21:17:43.563 I/DEBUG ( 157): #10 pc 00026c60 /system/lib/libdvm.so 01-01 21:17:43.564 I/DEBUG ( 157): #11 pc 0002ab4c /system/lib/libdvm.so (dvmInterpret(Thread*, Method const*, JValue*)+184) 01-01 21:17:43.564 I/DEBUG ( 157): #12 pc 0005f2b1 /system/lib/libdvm.so (dvmCallMethodV(Thread*, Method const*, Object*, bool, JValue*, std::__va_list)+272) 01-01 21:17:43.564 I/DEBUG ( 157): #13 pc 0005f2db /system/lib/libdvm.so (dvmCallMethod(Thread*, Method const*, Object*, JValue*, ...)+20) 01-01 21:17:43.564 I/DEBUG ( 157): #14 pc 00053e57 /system/lib/libdvm.so 01-01 21:17:43.564 I/DEBUG ( 157): #15 pc 0000e408 /system/lib/libc.so (__thread_entry+72) 01-01 21:17:43.564 I/DEBUG ( 157): #16 pc 0000daf4 /system/lib/libc.so (pthread_create+160) 01-01 21:17:43.565 I/DEBUG ( 157): 01-01 21:17:43.565 I/DEBUG ( 157): stack: 01-01 21:17:43.565 I/DEBUG ( 157): 5c775558 00000001 01-01 21:17:43.565 I/DEBUG ( 157): 5c77555c 4007a1b4 /system/lib/libc.so 01-01 21:17:43.565 I/DEBUG ( 157): 5c775560 4007a1b4 /system/lib/libc.so 01-01 21:17:43.565 I/DEBUG ( 157): 5c775564 4007a1b4 /system/lib/libc.so 01-01 21:17:43.565 I/DEBUG ( 157): 5c775568 4007a1b4 /system/lib/libc.so 01-01 21:17:43.566 I/DEBUG ( 157): 5c77556c 4004f3f9 /system/lib/libc.so (__sflush_locked+36) 01-01 21:17:43.566 I/DEBUG ( 157): 5c775570 4007a254 /system/lib/libc.so 01-01 21:17:43.566 I/DEBUG ( 157): 5c775574 4007a1b4 /system/lib/libc.so 01-01 21:17:43.567 I/DEBUG ( 157): 5c775578 00000000 01-01 21:17:43.567 I/DEBUG ( 157): 5c77557c 400503c9 /system/lib/libc.so (_fwalk+32) 01-01 21:17:43.567 I/DEBUG ( 157): 5c775580 4081cb58 /system/lib/libdvm.so 01-01 21:17:43.567 I/DEBUG ( 157): 5c775584 0000020c 01-01 21:17:43.567 I/DEBUG ( 157): 5c775588 00000000 01-01 21:17:43.567 I/DEBUG ( 157): 5c77558c 4081cec0 /system/lib/libdvm.so 01-01 21:17:43.567 I/DEBUG ( 157): 5c775590 df0027ad 01-01 21:17:43.568 I/DEBUG ( 157): 5c775594 00000000 01-01 21:17:43.568 I/DEBUG ( 157): #00 5c775598 00000000 01-01 21:17:43.568 I/DEBUG ( 157): 5c77559c 6c756e28 01-01 21:17:43.568 I/DEBUG ( 157): 5c7755a0 0000296c 01-01 21:17:43.569 I/DEBUG ( 157): 5c7755a4 00000000 01-01 21:17:43.569 I/DEBUG ( 157): 5c7755a8 00000000 01-01 21:17:43.569 I/DEBUG ( 157): 5c7755ac 00000000 01-01 21:17:43.569 I/DEBUG ( 157): 5c7755b0 00000000 01-01 21:17:43.569 I/DEBUG ( 157): 5c7755b4 00000000 01-01 21:17:43.570 I/DEBUG ( 157): 5c7755b8 00000000 01-01 21:17:43.570 I/DEBUG ( 157): 5c7755bc 00000000 01-01 21:17:43.570 I/DEBUG ( 157): 5c7755c0 00000000 01-01 21:17:43.570 I/DEBUG ( 157): 5c7755c4 00000000 01-01 21:17:43.570 I/DEBUG ( 157): 5c7755c8 00000000 01-01 21:17:43.571 I/DEBUG ( 157): 5c7755cc 00000000 01-01 21:17:43.571 I/DEBUG ( 157): 5c7755d0 00000000 01-01 21:17:43.571 I/DEBUG ( 157): 5c7755d4 00000000 01-01 21:17:43.571 I/DEBUG ( 157): ........ ........ 01-01 21:17:43.571 I/DEBUG ( 157): #01 5c7757b0 40c61bc8 /dev/ashmem/dalvik-heap (deleted) 01-01 21:17:43.572 I/DEBUG ( 157): 5c7757b4 000009b9 01-01 21:17:43.572 I/DEBUG ( 157): 5c7757b8 9b900019 01-01 21:17:43.572 I/DEBUG ( 157): 5c7757bc 40c61ba8 /dev/ashmem/dalvik-heap (deleted) 01-01 21:17:43.572 I/DEBUG ( 157): 5c7757c0 00000000 01-01 21:17:43.572 I/DEBUG ( 157): 5c7757c4 00000000 01-01 21:17:43.572 I/DEBUG ( 157): 5c7757c8 9b900019 01-01 21:17:43.573 I/DEBUG ( 157): 5c7757cc 407ae7e9 /system/lib/libdvm.so 01-01 21:17:43.573 I/DEBUG ( 157): #02 5c7757d0 5b1ed1a8 01-01 21:17:43.573 I/DEBUG ( 157): 5c7757d4 5a6ca710 01-01 21:17:43.574 I/DEBUG ( 157): 5c7757d8 00000000 01-01 21:17:43.574 I/DEBUG ( 157): 5c7757dc 00000001 01-01 21:17:43.574 I/DEBUG ( 157): 5c7757e0 5b1ed1a8
01-01 21:17:43.561 I/DEBUG ( 157): backtrace: 01-01 21:17:43.562 I/DEBUG ( 157): #00 pc 0004527c /system/lib/libdvm.so (dvmAbort+75) 01-01 21:17:43.562 I/DEBUG ( 157): #01 pc 00048499 /system/lib/libdvm.so 01-01 21:17:43.562 I/DEBUG ( 157): #02 pc 0004a7e5 /system/lib/libdvm.so 01-01 21:17:43.562 I/DEBUG ( 157): #03 pc 0003b87f /system/lib/libdvm.so 01-01 21:17:43.562 I/DEBUG ( 157): #04 pc 00016117 /system/lib/libjavacore.so 01-01 21:17:43.562 I/DEBUG ( 157): #05 pc 00019471 /system/lib/libjavacore.so 01-01 21:17:43.563 I/DEBUG ( 157): #06 pc 0001979b /system/lib/libjavacore.so 01-01 21:17:43.563 I/DEBUG ( 157): #07 pc 0001d850 /system/lib/libdvm.so (dvmPlatformInvoke+112) 01-01 21:17:43.563 I/DEBUG ( 157): #08 pc 0004ca1d /system/lib/libdvm.so (dvmCallJNIMethod(unsigned int const*, JValue*, Method const*, Thread*)+396) 01-01 21:17:43.563 I/DEBUG ( 157): #09 pc 000381d5 /system/lib/libdvm.so (dvmCheckCallJNIMethod(unsigned int const*, JValue*, Method const*, Thread*)+8) 01-01 21:17:43.563 I/DEBUG ( 157): #10 pc 00026c60 /system/lib/libdvm.so 01-01 21:17:43.564 I/DEBUG ( 157): #11 pc 0002ab4c /system/lib/libdvm.so (dvmInterpret(Thread*, Method const*, JValue*)+184) 01-01 21:17:43.564 I/DEBUG ( 157): #12 pc 0005f2b1 /system/lib/libdvm.so (dvmCallMethodV(Thread*, Method const*, Object*, bool, JValue*, std::__va_list)+272) 01-01 21:17:43.564 I/DEBUG ( 157): #13 pc 0005f2db /system/lib/libdvm.so (dvmCallMethod(Thread*, Method const*, Object*, JValue*, ...)+20) 01-01 21:17:43.564 I/DEBUG ( 157): #14 pc 00053e57 /system/lib/libdvm.so 01-01 21:17:43.564 I/DEBUG ( 157): #15 pc 0000e408 /system/lib/libc.so (__thread_entry+72) 01-01 21:17:43.564 I/DEBUG ( 157): #16 pc 0000daf4 /system/lib/libc.so (pthread_create+160)
所以我懷疑找錯了方向，那不是在VM掛掉之前log裡就有異常了？往上看，看到Failed adding to JNI pinned array ref table (1024 entries)，不能夠將jni裡指向的數組引用添加。再往上找看到關鍵的一句:ReferenceTable overflow (max=1024),經查是引用計數器溢出了，最大為1024.即java的內存管理機制是基於引用的，需要計數器來記錄引用的次數。在overflow這句話得後面當引用計數達到1024時還dump出了最近的10個引用，Summary了哪些引用有多少個，可以看到有1019個對int[]數組的引用，剩下的是對char[]的引用。我恍然大悟，我在jni裡不停的通過下面來接收int數組，將其轉為opencv的mat矩陣:
jint *cbuf;
cbuf = env->GetIntArrayElements(buf, false);
if(cbuf == NULL)
{
return ;
}
Mat mat(h, w, CV_8UC4, (unsigned char*)cbuf);卻一直沒有釋放。想到這，又搜了下資料，參考這裡 在原有代碼基礎上增加釋放cbuf的語句就ok了:env->ReleaseIntArrayElements(buf, cbuf, 0);參考Android NDK之JNI陷阱 在用到NewByteArray類似方法時一定要DeleteLocalRef()，使用GetByteArrayELement時(本文即使如此)要用ReleaseByteArrayElements來進行釋放。
稍後，會介紹Android和JNI層的OpenCV交互時，關於怎麼傳數據的兩種方法，本例中使用的是傳int數組的方法，如果有圖片需要返回，就再返回一個jnitArray。
結語: 碰到內存洩漏或異常的問題不要怕，尋根探源只要能定位到問題便解決了一大半了。正如六祖曰煩惱即菩提，李小龍說問題即答案，當你真正明白了問題，也就找到了答案！呵呵，漫漫程序路, 何嘗不是如此呢。。。
--------------------------------------------------------本文系原創，轉載請注明作者:yanzi1225627
android 驗證碼之短信驗證（雲之訊短信平台）
好久沒更新過博客了。這段時間總算是忙完了，抽點時間出來更新下博客。這次跟大家帶來的是一個很簡單的短信驗證碼。相信這個驗證碼的功能基本上99的項目都需要用到，我這裡是用的雲
Android開發之鬼迷心竅(一)
由於第一次寫博客，裡面難免有些錯誤與不足，希望大家可以幫忙多多指點。下面我將從三個方面給大家介紹一下android開發吧，也是對我前一段時間學習的總結吧。第一，Andro
android屏幕分類與屏幕相關參數定義
android設備運行在各種不同的屏幕中，這些屏幕有著不同的screen sizes（屏幕大小）和screen densities（屏幕密度）。screen sizes表
android中Activity詳解（生命周期、以各種方式啟動Activity、狀態保存，完全退出等）
一、什麼是Activity？簡單的說：Activity就是布滿整個窗口或者懸浮於其他窗口上的交互界面。在一個應用程序中通常由多個Activity構成，都會在Manifes
