double 和 float 性能差別測試

操做double大概是float的3倍的時間消耗。

 

public class DoubleFloatComparation {
    public static void main(String args[]) {    
     
     //double float comparation
     long start2 = System.nanoTime();
     float f = 0f;
     for(int i = 0; i< Integer.MAX_VALUE; i++){
      f += 0.1;
     }
     long end2 = System.nanoTime();
        System.out.println(end2 - start2);
     
        long start3 = System.nanoTime();
        double d = 0d;
        for(int i = 0; i< Integer.MAX_VALUE; i++){
         d += 0.1;
        }
        long end3 = System.nanoTime();
        System.out.println(end3 - start3);
        
    }
}