List of Permission in android

<uses-permission android:name="android.permission.ACCESS_CHECKIN_PROPERTIES" />
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_LOCATION_EXTRA_COMMANDS" />
<uses-permission android:name="android.permission.ACCESS_MOCK_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<uses-permission android:name="android.permission.ACCESS_SURFACE_FLINGER" />
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
<uses-permission android:name="android.permission.ACCOUNT_MANAGER" />
<uses-permission android:name="android.permission.AUTHENTICATE_ACCOUNTS" />
<uses-permission android:name="android.permission.BATTERY_STATS" />
<uses-permission android:name="android.permission.BIND_APPWIDGET" />
<uses-permission android:name="android.permission.BIND_DEVICE_ADMIN" />
<uses-permission android:name="android.permission.BIND_INPUT_METHOD" />
<uses-permission android:name="android.permission.BIND_REMOTEVIEWS" />
<uses-permission android:name="android.permission.BIND_WALLPAPER" />
<uses-permission android:name="android.permission.BLUETOOTH" />
<uses-permission android:name="android.permission.BLUETOOTH_ADMIN" />
<uses-permission android:name="android.permission.BRICK" />
<uses-permission android:name="android.permission.BROADCAST_PACKAGE_REMOVED" />
<uses-permission android:name="android.permission.BROADCAST_SMS" />
<uses-permission android:name="android.permission.BROADCAST_STICKY" />
<uses-permission android:name="android.permission.BROADCAST_WAP_PUSH" />
<uses-permission android:name="android.permission.CALL_PHONE"/>
<uses-permission android:name="android.permission.CALL_PRIVILEGED" />
<uses-permission android:name="android.permission.CAMERA"/>
<uses-permission android:name="android.permission.CHANGE_COMPONENT_ENABLED_STATE" />
<uses-permission android:name="android.permission.CHANGE_CONFIGURATION" />
<uses-permission android:name="android.permission.CHANGE_NETWORK_STATE" />
<uses-permission android:name="android.permission.CHANGE_WIFI_MULTICAST_STATE" />
<uses-permission android:name="android.permission.CHANGE_WIFI_STATE" />
<uses-permission android:name="android.permission.CLEAR_APP_CACHE" />
<uses-permission android:name="android.permission.CLEAR_APP_USER_DATA" />
<uses-permission android:name="android.permission.CONTROL_LOCATION_UPDATES" />
<uses-permission android:name="android.permission.DELETE_CACHE_FILES" />
<uses-permission android:name="android.permission.DELETE_PACKAGES" />
<uses-permission android:name="android.permission.DEVICE_POWER" />
<uses-permission android:name="android.permission.DIAGNOSTIC" />
<uses-permission android:name="android.permission.DISABLE_KEYGUARD" />
<uses-permission android:name="android.permission.DUMP" />
<uses-permission android:name="android.permission.EXPAND_STATUS_BAR" />
<uses-permission android:name="android.permission.FACTORY_TEST" />
<uses-permission android:name="android.permission.FLASHLIGHT" />
<uses-permission android:name="android.permission.FORCE_BACK" />
<uses-permission android:name="android.permission.GET_ACCOUNTS" />
<uses-permission android:name="android.permission.GET_PACKAGE_SIZE" />
<uses-permission android:name="android.permission.GET_TASKS" />
<uses-permission android:name="android.permission.GLOBAL_SEARCH" />
<uses-permission android:name="android.permission.HARDWARE_TEST" />
<uses-permission android:name="android.permission.INJECT_EVENTS" />
<uses-permission android:name="android.permission.INSTALL_LOCATION_PROVIDER" />
<uses-permission android:name="android.permission.INSTALL_PACKAGES" />
<uses-permission android:name="android.permission.INTERNAL_SYSTEM_WINDOW" />
<uses-permission android:name="android.permission.INTERNET"/>
<uses-permission android:name="android.permission.KILL_BACKGROUND_PROCESSES" />
<uses-permission android:name="android.permission.MANAGE_ACCOUNTS" />
<uses-permission android:name="android.permission.MANAGE_APP_TOKENS" />
<uses-permission android:name="android.permission.MASTER_CLEAR" />
<uses-permission android:name="android.permission.MODIFY_AUDIO_SETTINGS" />
<uses-permission android:name="android.permission.MODIFY_PHONE_STATE" />
<uses-permission android:name="android.permission.MOUNT_FORMAT_FILESYSTEMS" />
<uses-permission android:name="android.permission.MOUNT_UNMOUNT_FILESYSTEMS" />
<uses-permission android:name="android.permission.NFC" />
<uses-permission android:name="android.permission.PROCESS_OUTGOING_CALLS" />
<uses-permission android:name="android.permission.READ_CALENDAR" />
<uses-permission android:name="android.permission.READ_CONTACTS" />
<uses-permission android:name="android.permission.READ_FRAME_BUFFER" />
<uses-permission android:name="android.permission.READ_HISTORY_BOOKMARKS" />
<uses-permission android:name="android.permission.READ_INPUT_STATE" />
<uses-permission android:name="android.permission.READ_LOGS" />
<uses-permission android:name="android.permission.READ_PHONE_STATE" />
<uses-permission android:name="android.permission.READ_SMS" />
<uses-permission android:name="android.permission.READ_SYNC_SETTINGS" />
<uses-permission android:name="android.permission.READ_SYNC_STATS" />
<uses-permission android:name="android.permission.REBOOT" />
<uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED" />
<uses-permission android:name="android.permission.RECEIVE_MMS" />
<uses-permission android:name="android.permission.RECEIVE_SMS" />
<uses-permission android:name="android.permission.RECEIVE_WAP_PUSH" />
<uses-permission android:name="android.permission.RECORD_AUDIO" />
<uses-permission android:name="android.permission.REORDER_TASKS" />
<uses-permission android:name="android.permission.RESTART_PACKAGES" />
<uses-permission android:name="android.permission.SEND_SMS" />
<uses-permission android:name="android.permission.SET_ACTIVITY_WATCHER" />
<uses-permission android:name="android.permission.SET_ALARM" />
<uses-permission android:name="android.permission.SET_ALWAYS_FINISH" />
<uses-permission android:name="android.permission.SET_ANIMATION_SCALE" />
<uses-permission android:name="android.permission.SET_DEBUG_APP" />
<uses-permission android:name="android.permission.SET_ORIENTATION" />
<uses-permission android:name="android.permission.SET_POINTER_SPEED" />
<uses-permission android:name="android.permission.SET_PROCESS_LIMIT" />
<uses-permission android:name="android.permission.SET_TIME" />
<uses-permission android:name="android.permission.SET_TIME_ZONE" />
<uses-permission android:name="android.permission.SET_WALLPAPER" />
<uses-permission android:name="android.permission.SET_WALLPAPER_HINTS" />
<uses-permission android:name="android.permission.SIGNAL_PERSISTENT_PROCESSES" />
<uses-permission android:name="android.permission.STATUS_BAR" />
<uses-permission android:name="android.permission.SUBSCRIBED_FEEDS_READ" />
<uses-permission android:name="android.permission.SUBSCRIBED_FEEDS_WRITE" />
<uses-permission android:name="android.permission.SYSTEM_ALERT_WINDOW" />
<uses-permission android:name="android.permission.UPDATE_DEVICE_STATS" />
<uses-permission android:name="android.permission.USE_CREDENTIALS" />
<uses-permission android:name="android.permission.USE_SIP" />
<uses-permission android:name="android.permission.VIBRATE" />
<uses-permission android:name="android.permission.WAKE_LOCK" />
<uses-permission android:name="android.permission.WRITE_APN_SETTINGS" />
<uses-permission android:name="android.permission.WRITE_CALENDAR" />
<uses-permission android:name="android.permission.WRITE_CONTACTS" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.WRITE_GSERVICES" />
<uses-permission android:name="android.permission.WRITE_HISTORY_BOOKMARKS" />
<uses-permission android:name="android.permission.WRITE_SECURE_SETTINGS" />
<uses-permission android:name="android.permission.WRITE_SETTINGS" />
<uses-permission android:name="android.permission.WRITE_SMS" />
<uses-permission android:name="android.permission.WRITE_SYNC_SETTINGS" />

Double Pointer (Pointer to Pointer) some input

 A double pointer has two basic meanings.
        One is of a pointer to a pointer, where changing the value of double pointer will result in the original pointer being changed.
        Another is that of a two-dimensional array, such as a matrix

Example for Two dimensional array
int main( int argc, char **argv (or) char* argv[] )
{
// print the first string
printf("%s\n", argv[0]);

return 0;
}

The other example where the double pointer is a pointer to a pointer, lets say you have a function foo() that allocates memory for a pointer that was declared in function main()

void foo( char ** ptr)
{
*ptr = malloc(255); // allocate some memory
strcpy( *ptr, "Hello World");
}

int main()
{
char *ptr = 0;
// call function with a pointer to pointer
foo( &ptr );
printf("%s\n", ptr);
// free up the memory
free(ptr);

return 0;
}

Creating 2D int array
//Create your pointer
int **ptr;
//Assign first dimension
ptr = new int*[5];
//Assign second dimension
for(int i = 0; i < 5; i++)
ptr[i] = new int[5];
Deleting 2D array
for (int x = 0; x < nCol; ++x)
delete [] ptr[x];
delete [] ptr;

How delete[] knows how many items to be destroyed ??
 When an array is created with new[], the size of array is stored in the metadata at the memory block. delete[] makes use of that information.

New[] operator requires default constructor  , for ex
   student* kar = new student[10](34,"");  // its completely wrong
  student * kar = new student[10];   // Correct

new & delete are based on malloc & free. Malloc additionally allocate a header storing the size allocated, so free() knows the size to free. new[] not only keeps the malloc header, but also has an extra header storing the size of the array/vector, so delete[] knows how many objects are in the array/vector, and thus knows how many times to call the destructor.

Allocation Using	Deallocation using	Result	Remarks
new	delete	Ok
new[]	delete[]	Ok
new	delete[]	The vector delete will try to delete more objects depending on the random value it gets from its object-count location and will obviously result in heap corruption.	Compiler will not track the Pointer, Its developer responsibility to call the respective delete operator (ie delete or delete[])
new[]	delete	Memory leak	It will delete only first item in the array

JNI step by step

1. Add native method in your activity class
    for instance : public native String display(boolean status);

2. open command prompt and go to bin/classes
    Example :~/workspace/test/bin/classes$ javah -jni com.example.test.MainActivity
    Abstract :~/workspace/test/bin/classes$ javah -jni <class name where u have added your native API>

    as a result , a header file will be created in   "test/bin/classes/"
3. Copy that header file and paste it in to jni folder (create jni folder in the project )

4. Using signature of the header , create the cpp file and have definition for that method

5. Create Android.mk file (add the cpp file and module name inside it)

6. go to the project
    Example:~/workspace/test$ "ndk-build.cmd"
    result : this will create lib (under the libs folder)

7. now, you can call the native method from the application