Why does the division of two integers return 0.0 in Java? [duplicate]

Question

int totalOptCount = 500;
int totalRespCount=1500; 
float percentage =(float)(totalOptCount/totalRespCount);

Why does this always return value 0.0? Also I want to format this into 00.00 format and convert into string?

Answer 1

Because the conversion to float happens after the division has been done. You need:

float percentage = ((float) totalOptCount) / totalRespCount;

You should be able to format using something like:

String str = String.format("%2.02f", percentage);

Answer 2

If you are using int values, using a double may be a better choice and have less rounding error. float can represent int values without error up to ~16 million. double can accurately represent all int values.

double percentage =(double) totalOptCount / totalRespCount;

Percentages are usually multiplied by 100, meaning you can drop the cast.

double percentage = 100.0 * totalOptCount / totalRespCount;