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Initialize a long in Java

Primitive Data Types - oracle doc says the range of long in Java is -9,223,372,036,854,775,808 to 9,223,372,036,854,775,807. But when I do something like this in my eclipse

long i = 12345678910;

it shows me "The literal 12345678910 of type int is out of range" error.

There are 2 questions.

1) How do I initialize the long with the value 12345678910?

2) Are all numeric literals by default of type int?

And how about initializing a Long?
@WolfgangFahl Same rules for Long - due to auto-boxing, you can use Long i = 12345678910L, or use Long i = Long.valueOf(12345678910L) for those cases where you cannot use auto-boxing.

M
MByD

You should add L: long i = 12345678910L;. Yes.

BTW: it doesn't have to be an upper case L, but lower case is confused with 1 many times :).


Just in case someone was wondering: the same goes for hex, e.g. 0x200000000L
@Victor Long.valueOf(long) returns a Long, not a primitive long. MByD's solution avoids to rely on auto-boxing.
@user149408 Perhaps you mean 0x20000000L?
@Pluto 0x20000000L would work but can still be represented by int (a 32-bit integer), thus 0x20000000 would work just as well. 0x200000000L breaks that boundary, making the trailing L necessary.
J
Jack Edmonds

You need to add the L character to the end of the number to make Java recognize it as a long. long i = 12345678910L; Yes.

See Primitive Data Types which says "An integer literal is of type long if it ends with the letter L or l; otherwise it is of type int."


A
Amir Raminfar

You need to add uppercase L at the end like so

long i = 12345678910L;

Same goes true for float with 3.0f

Which should answer both of your questions


S
Shawn Mehan

To initialize long you need to append "L" to the end. It can be either uppercase or lowercase.

All the numeric values are by default int. Even when you do any operation of byte with any integer, byte is first promoted to int and then any operations are performed.

Try this

byte a = 1; // declare a byte
a = a*2; //  you will get error here

You get error because 2 is by default int.
Hence you are trying to multiply byte with int. Hence result gets typecasted to int which can't be assigned back to byte.