import java.util.*;
import java.io.*;

public class CountLetters	// class to count the number each letter found in a text file (uses a TreeMap), we will use only lower case letters, lower casing any upper case letter
{	
	public static void main(String[] args)
	{
		String filename;
		TreeMap<Character,Integer> map=new TreeMap<>();	// our TreeMap will store the letter as the key and the count of occurrences as the value
		char current;			// current letter being looked at in the file, also used to create our hash map
		Integer i;				// temp Integer variable used when increment the count by 1
		String temp;			// the next word input
		for(int j=0;j<26;j++)	
		{
			current=new Character((char)('a'+j));	// set up the map to have the 26 lower case letters as Characters, with an initial value of 0
			map.put(current,0);
		}
		try {
			Scanner in1=new Scanner(System.in);				// keyboard input to get the filename
			System.out.print("Enter the file name:  ");
			filename=in1.next();
			Scanner in2=new Scanner(new File(filename));	// file input
			while(in2.hasNext())							// read the file one String at a time
			{
				temp=in2.next().toLowerCase();				// get the next String, lower case it
				for(int j=0;j<temp.length();j++)			// iterate for each character in the string
				{
					current=temp.toLowerCase().charAt(j);	// get the next character of this string, lower case it if its a letter
					if(Character.isLetter(current))			// if it is a letter, we have to count it
					{
						i=map.get(current);					// retrieve the value from the map element matching this key (current)
						i=new Integer(i.intValue()+1);		// create a new Integer 1 greater
						map.put(current,i);					// replace the key-value pair in map with the new key-value pair of current (the letter) and the new Integer
					}
				}
			}
			System.out.println(map);		// we are using a TreeMap instead of a HashMap so that the items print out in order
		}
		catch(IOException e)								// needed if the file does not exist or is
		{													// corrupted
			System.out.println(e);
		}
	}
}