java文件如何统计字母出现的次数和百分比

package com.keshangone;
import java.io.File;
import java.util.Scanner;
import java.io.FileNotFoundException;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Set;
public class shouzimu {

  public static <type> void main (String[] args) throws FileNotFoundException {
    File file=new File("D:\\新建文件夹 (6)\\wen.txt"); 
    if(!file.exists()){
      System.out.println("文件打开错误");
      return;
    } 
    
    int []num=new int[100];
    char []zimu=new char[100];
    char a='A';char b='a';
    for(int i=1;i<=52;i++)
    {
      if(i<=26)
        zimu[i]=a++;
      else
        zimu[i]=b++;
    }
    
    
    Scanner scanner=new Scanner(file);
    HashMap<String,Integer> hashMap=new HashMap<String,Integer>();
    while(scanner.hasNextLine()) {
      String line=scanner.nextLine();
      String[] lineWords=line.split(" ");     //    £  DZ ע ͵  
      for(int i=0;i<lineWords.length;i++) {
        
        for(int j=0;j<lineWords[i].length();j++)
        {
          if(lineWords[i].charAt(j)>='A'&&lineWords[i].charAt(j)<='Z')
            num[lineWords[i].charAt(j)-'A'+1]++;
          else if(lineWords[i].charAt(j)>='a'&&lineWords[i].charAt(j)<='z')
            num[lineWords[i].charAt(j)-'a'+1+24]++;
        }
      }
    }
    int sum=0;
    for(int i=1;i<=52;i++)
    {
      sum+=num[i];
    }
    for(int i=1;i<=52;i++)
    {
      for(int j=i+1;j<=52;j++)
      {
        if(num[i]<num[j])
        {
          int t=num[i];
          num[i]=num[j];
          num[j]=t;
          
          char s=zimu[i];
          zimu[i]=zimu[j];
          zimu[j]=s;
        }
      }
    }
    System.out.println(sum);
    for(int i=1;i<=52;i++)
    {
      double ans=num[i]*1.0/sum;
      System.out.print(zimu[i]+":"+num[i]+"  ");
      String wen=String.format("%.2f", ans*100);
      System.out.println(wen+" %");
    }
}
}