I have wrong answer for Project-Euler#26

I can't know why wrong this question. This problem =

A unit fraction contains 1 in the numerator. The decimal representation of the unit fractions with denominators 2 to 10 are given:

1/2 = 0.5 1/3 = 0.(3) 1/4 = 0.25 1/5 = 0.2 1/6 = 0.1(6) 1/7 = 0.(142857) 1/8 = 0.125 1/9 = 0.(1) 1/10 = 0.1

Where 0.1(6) means 0.166666..., and has a 1-digit recurring cycle. It can be seen that 1/7 has a 6-digit recurring cycle.

Find the value of d < 1000 for which 1/d contains the longest recurring cycle in its decimal fraction part.

public static void main(String[] args) 
{
    String str="";
    double bignumber=0; 
    double temp=0;
    for (double i= 2; i < 1000; i++) 
    {
        double result= 1/i;
        str+=result;
        temp=str.length()-2;
        if(temp>bignumber)
        {
            bignumber=temp;
        }
            str="";
    }
        System.out.println(bignumber);
}