Most efficient way to convert java.lang.Long to primitive int

Question

I have a weird scenario where I need to convert several million java.lang.Longs into primitive int types. I need to do this several times a day, every single day. Normally, I wouldn't worry about this kind of simple casting, but since it's happening so much, so often, I have to ask: what's the most efficient way to do this, and why?

My first attempt:

Long myLong = getLong();
int x = Integer.valueOf(myLong.toString())

Although this seems like going 3 sides around the barn. Thanks in advance.

Just use `intValue()`, and recognize you'll lose data unless your longs are restricted. — Dave Newton, Jan 05 '13 at 15:41
Do not convert `Long` to `String` and tha parse it to get an `int`. — MrSmith42, Jan 05 '13 at 15:42
If your values fit in an `int`, replace your `Long` variables by `Integer` — MrSmith42, Jan 05 '13 at 15:43

score 24 · Accepted Answer · answered Jan 05 '13 at 15:41

24

The Long class has an .intValue() method, I guess this is what you are looking for...

(warning, you may lose precision etc etc -- but you probably know that already)

answered Jan 05 '13 at 15:41

fge

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score 9 · Answer 2 · answered Jan 05 '13 at 15:40

9

Try this

int x = myLong.intValue( );

answered Jan 05 '13 at 15:40

Alexander Pogrebnyak

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I am getting the error: Cannot invoke intValue() on the primitive type long – Anand Jul 22 '16 at 08:24
1

@Anand. `myLong` has to be declared as `Long` not `long`. For latter case just cast it, i.e. `(int) myPrimitiveLong`. – Alexander Pogrebnyak Jul 22 '16 at 19:25

score -2 · Answer 3 · edited May 13 '14 at 13:27

-2

Try this

Integer i = (int) (long) b;

edited May 13 '14 at 13:27

coder

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answered May 13 '14 at 12:35

user2144695

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Most efficient way to convert java.lang.Long to primitive int

3 Answers3