Use 'L' instead of 'l' at the end of integer constants (UL)

Description:

It is difficult to distinguish the lower case letter 'l' from the digit '1'. When the letter 'l' is used as the long modifier at the end of an integer constant, it can be confused with digits. In this case, it is better to use an uppercase 'L'.

Incorrect:

long bitMask = 0x3ffe00000001l;

Correct:

long bitMask = 0x3ffe00000001L;