java 倒入一篇文章，显示每个字母的出现概率，从大到小排序

package com_1;
import java.io.BufferedReader;
import java.io.FileReader;
import java.io.IOException;
import java.math.BigInteger;
import java.text.DecimalFormat;
import java.util.ArrayList;
import java.util.Comparator;
import java.util.TreeMap;
import java.util.TreeSet;
public class Shuru2
{
    public static void main(String [] args) throws IOException {
        BufferedReader br=new BufferedReader(new FileReader("F:\\eclipse-workspace\\com_1\\src\\1.txt"));        
        TreeMap<Character,Integer> hm=new TreeMap<>();
        int  bb;
        while((bb=br.read())!=-1) {    
             if((bb>='A'&&bb<='Z')||(bb>'a'&&bb<='z')) {
                 hm.put((char)bb,hm.containsKey((char)bb)?hm.get((char)bb)+1:1);
            }
            
            }    
        br.close();
        int max=0;
        int sum=0;
        int t=0;
        for(Character k: hm.keySet()) {
            sum=sum+hm.get(k);
          }
        TreeSet<Character> ts=new TreeSet<>(new Comparator<Character>()
        {
            public int compare(Character a,Character b) {
                int num=hm.get(a)-hm.get(b);
                return num==0?1:(-num);
            }
        });
        for(Character k: hm.keySet()) {
            ts.add(k);
        }
        DecimalFormat df = new DecimalFormat("0.00%");
        for (Character c : ts)
        {
            float bai=(float)hm.get(c)/sum;
           
            System.out.println(c+" "+hm.get(c)+" "+df.format(bai));
        }
          
        
        
        //System.out.println(sum);
}}

整个人都不好了