import java.io.File;
import java.io.IOException;
import java.text.DecimalFormat;
import java.util.Arrays;
import java.util.Scanner;

public class ScannerExample {

	public static void main(String[] args) {

		// To count the number of occurences of a, b, c...
		int[] count = new int[26];

		String fileName = "SomeText.txt";
		File file = new File(fileName);
		try {
			Scanner scan = new Scanner(file);
			while (scan.hasNextLine()) {
				String line = scan.nextLine();
				countLetters(count, line);
			}
			printPercentages(count);
		} catch (IOException e) {
			System.out.println("Problem opening the file");
		}
	}

	public static void countLetters(int[] count, String line) {
		line = line.toLowerCase();
		for (int i = 0; i < line.length(); i++) {
			char c = line.charAt(i);
			if (c >= 'a' && c <= 'z') {
				int index = c - 'a';
				count[index]++;
			}
		}
	}

	public static void printPercentages(int[] count) {
		int totalLetters = 0;
		for (int i = 0; i < count.length; i++) {
			totalLetters += count[i];
		}
		DecimalFormat df = new DecimalFormat("0.00");
		for (int i = 0; i < count.length; i++) {
			// Math.max to guard against a division by 0
			double p = 100.0 * count[i] / 
			             Math.max(totalLetters, 1);
			System.out.println((char) (i + 'a') + " = " + 
					df.format(p) + "%");
		}
	}

}