New to Java

Hello,

I would like to count the number of whitespaces(Tab,Return,Spaces) in a given file I have tried so many times but I don't know why it's not working here is my code.

while (fileScan.hasNext()) { 
			count++;
			String str=fileScan.next();
		
			char[] chars =str.toCharArray();
			int i;
			for (i=0; i<str.length(); i++)		
			{		
				//Uppercase Letters
				if (Character.isUpperCase(chars))				

					caps++;	

				//Lowercase Letters

				else if(Character.isLowerCase(chars[i]))

					lows++;

				//Other Characters

				else if(!Character.isLetter(chars[i]))

					OtherCharachters++;

				//Whitespaces

				else if((chars[i]==' ')||(chars[i]=='\n')||(chars[i]=='\t'))

					numOfWhitespaceChars++;

			}	

		}
Thanks all inadvance.