Long

layout: default title: long for Large Number

When Java sees a whole number, it assumes it is looking at an int.

The max value of an int is 2_147_483_647, so what if we need a number larger than that?

int tooBig = 2_200_000_000; // WILL NOT COMPILE
                            // "The literal 2_200_000_000 of type int is out of range"

We can add L or l to a value to tell Java it is a long. (Most developers use L because it is more readable.)

We then have to assign it to a long variable.

long bigNum = 2_200_000_000L;

We must add the L to a literal that's outside the range of an int:

long num = 2_200_000_000; // WILL NOT COMPILE

We can add L to a number in the range of an int, but then we must assign it to a long variable.

Once we add the L, the number occupies 8 bytes in memory.

int littleNum = 1L; // WILL NOT COMPILE
                    // long takes 8 bytes, int takes 4.