How do I cast a double to an int in Java?

Question

I'm looking at http://docs.oracle.com/javase/6/docs/api/java/lang/Double.html

I am trying

    double b = Math.sqrt(absoluteNumber);
    int c = b.intValue();

but I am getting this error:

Factorise.java:13: error: double cannot be dereferenced
int c = b.intValue();

Help please?

possible duplicate of [How to cast a double to an int in Java?](http://stackoverflow.com/questions/2143476/how-to-cast-a-double-to-an-int-in-java) — La-comadreja, Apr 29 '14 at 21:19

score 15 · Accepted Answer · answered Nov 17 '12 at 17:23

15

double is not an object, it is a primitive type.

Simply writing (int)b will do the job.

If you really need a Double object, you need to construct one.

answered Nov 17 '12 at 17:23

bmargulies

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score 6 · Answer 2 · edited Nov 28 '12 at 05:03

6

double is a "primitive type", it doesn't have an intValue() method (in fact it doesn't have any methods, as it is a primitive). Try the Double wrapper class, which has an intValue() method.

Double b = Math.sqrt(absoluteNumber);
int c = b.intValue();

Or simply use casting:

double b = Math.sqrt(absoluteNumber);
int c = (int) b;

edited Nov 28 '12 at 05:03

Dave Newton

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answered Nov 17 '12 at 17:22

PermGenError

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Using `Double` in this case is overkill, casting would be better. – arshajii Nov 17 '12 at 17:28
@A.R.S. true, i was actually pointing the mistake, however, i mentioned about primitive castingin my answer now cheers :) – PermGenError Nov 17 '12 at 17:29

score 3 · Answer 3 · answered Nov 17 '12 at 17:21

3

You may simply cast it:

int c = (int)b;

answered Nov 17 '12 at 17:21

kosa

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score 1 · Answer 4 · edited Feb 09 '17 at 11:44

The specific compile time error in your class is the result of trying to call a method on a value which was declared as a primitive type. Primitive types are not Objects and thus do not have properties. Hence they do not have any methods.

You could either cast the primitive double value to a primitive intvalue,

double b = Math.sqrt(absoluteNumber) ;
int a = (int) b ;

or cast the double to a Double---using a Java feature called auto-boxing---in order to use the intValue method of the Number interface implemented by the Double class:

double b = Math.sqrt(absoluteNumber) ;
int a = ( (Double) b ).intValue( ) ;

Another way is to use the valueOf and intValue methods of the Double class:

double b = Math.sqrt(absoluteNumber) ;
int a = ( Double.valueOf(b) ).intValue( ) ;

score 0 · Answer 5 · answered Nov 17 '12 at 17:24

0

Try

public static void main(String[] args) {
        Double  b = Math.sqrt(43253);
        int c = b.intValue();

        System.out.println("#### S = " + c);

    }

Output

#### S = 207

answered Nov 17 '12 at 17:24

Bhavik Ambani

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Using `Double` in this case is overkill, casting would be better. – arshajii Nov 17 '12 at 17:26
Still this can also be considered as an option – Bhavik Ambani Nov 17 '12 at 17:27

score 0 · Answer 6 · edited Nov 17 '12 at 18:16

0

This simple line will do the job.

integer_var_name = (int) double_var_name;

edited Nov 17 '12 at 18:16

Jagger

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answered Nov 17 '12 at 17:57

scanE

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How do I cast a double to an int in Java?

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