Невозможно найти '.' символ в ArrayList:
public class ArrayTools
{
//instance variables and constructors could be present, but are not necessary
//sumSection will return the sum of the numbers
//from start to stop, not including stop
public static int sumSection(int[] numArray, int start, int stop)
{
int sum=0;
for ( int i = start; i < stop; i++)
{
sum += numArray.get(i);
}
return sum;
}
Подробнее здесь: https://stackoverflow.com/questions/350 ... -arraylist